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Al-Osaimi HM, Kanan M, Marghlani L, Al-Rowaili B, Albalawi R, Saad A, Alasmari S, Althobaiti K, Alhulaili Z, Alanzi A, Alqarni R, Alsofiyani R, Shrwani R. A systematic review on malaria and dengue vaccines for the effective management of these mosquito borne diseases: Improving public health. Hum Vaccin Immunother 2024; 20:2337985. [PMID: 38602074 PMCID: PMC11017952 DOI: 10.1080/21645515.2024.2337985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 03/28/2024] [Indexed: 04/12/2024] Open
Abstract
Insect vector-borne diseases (VBDs) pose significant global health challenges, particularly in tropical and subtropical regions. The WHO has launched the "Global Vector Control Response (GVCR) 2017-2030" to address these diseases, emphasizing a comprehensive approach to vector control. This systematic review investigates the potential of malaria and dengue vaccines in controlling mosquito-borne VBDs, aiming to alleviate disease burdens and enhance public health. Following PRISMA 2020 guidelines, the review incorporated 39 new studies out of 934 identified records. It encompasses various studies assessing malaria and dengue vaccines, emphasizing the significance of vaccination as a preventive measure. The findings indicate variations in vaccine efficacy, duration of protection, and safety considerations for each disease, influencing public health strategies. The review underscores the urgent need for vaccines to combat the increasing burden of VBDs like malaria and dengue, advocating for ongoing research and investment in vaccine development.
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Affiliation(s)
- Hind M. Al-Osaimi
- Department of Pharmacy Services Administration, King Fahad Medical City, Riyadh Second Health Cluster, Riyadh, Kingdom of Saudi Arabia
| | - Mohammed Kanan
- Department of Clinical Pharmacy, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Lujain Marghlani
- Department of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Kingdom of Saudi Arabia
| | - Badria Al-Rowaili
- Pharmaceutical Services Department, Northern Area Armed Forces Hospital, King Khalid Military, Hafr Al Batin, Kingdom of Saudi Arabia
| | - Reem Albalawi
- Department of Medicine, Tabuk University, Tabuk, Kingdom of Saudi Arabia
| | - Abrar Saad
- Pharmacy Department, Royal Commission Hospital, Yanbu, Kingdom of Saudi Arabia
| | - Saba Alasmari
- Department of Clinical Pharmacy, King Khalid University, Jeddah, Kingdom of Saudi Arabia
| | - Khaled Althobaiti
- Department of Medicine, Taif University, Ta’if, Kingdom of Saudi Arabia
| | - Zainab Alhulaili
- Department of Clinical Pharmacy, Dammam Medical Complex, Dammam, Kingdom of Saudi Arabia
| | - Abeer Alanzi
- Department of Medicine, King Abdulaziz Hospital, Makkah, Kingdom of Saudi Arabia
| | - Rawan Alqarni
- Department of Medicine and Surgery, King Khalid University, Abha, Kingdom of Saudi Arabia
| | - Razan Alsofiyani
- Department of Medicine, Taif University, Ta’if, Kingdom of Saudi Arabia
| | - Reem Shrwani
- Department of Clinical Pharmacy, Jazan University, Jazan, Kingdom of Saudi Arabia
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Rohokale R, Guo J, Guo Z. Monophosphoryl Lipid A-Rhamnose Conjugates as a New Class of Vaccine Adjuvants. J Med Chem 2024; 67:7458-7469. [PMID: 38634150 PMCID: PMC11081837 DOI: 10.1021/acs.jmedchem.3c02385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Adjuvant is an integral part of all vaccine formulations but only a few adjuvants with limited efficacies or application scopes are available. Thus, developing more robust and diverse adjuvants is necessary. To this end, a new class of adjuvants having α- and β-rhamnose (Rha) attached to the 1- and 6'-positions of monophosphoryl lipid A (MPLA) was designed, synthesized, and immunologically evaluated in mice. The results indicated a synergistic effect of MPLA and Rha, two immunostimulators that function via interacting with toll-like receptor 4 and recruiting endogenous anti-Rha antibodies, respectively. All the tested MPLA-Rha conjugates exhibited potent adjuvant activities to promote antibody production against both protein and carbohydrate antigens. Overall, MPLA-α-Rha exhibited better activities than MPLA-β-Rha, and 6'-linked conjugates were slightly better than 1-linked ones. Particularly, MPLA-1-α-Rha and MPLA-6'-α-Rha were the most effective adjuvants in promoting IgG antibody responses against protein antigen keyhole limpet hemocyanin and carbohydrate antigen sTn, respectively.
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Affiliation(s)
- Rajendra Rohokale
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Jiatong Guo
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
- UF Health Cancer Center, University of Florida, Gainesville, FL 32611, USA
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Lyimo BM, Bakari C, Popkin-Hall ZR, Giesbrecht DJ, Seth MD, Pereus D, Shabani ZI, Moshi R, Boniface R, Mandara CI, Madebe R, Juliano JJ, Bailey JA, Ishengoma DS. Genetic polymorphism and evidence of signatures of selection in the Plasmodium falciparum circumsporozoite protein gene in Tanzanian regions with different malaria endemicity. Malar J 2024; 23:139. [PMID: 38720288 PMCID: PMC11080125 DOI: 10.1186/s12936-024-04974-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 05/03/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND In 2021 and 2023, the World Health Organization approved RTS,S/AS01 and R21/Matrix M malaria vaccines, respectively, for routine immunization of children in African countries with moderate to high transmission. These vaccines are made of Plasmodium falciparum circumsporozoite protein (PfCSP), but polymorphisms in the gene raise concerns regarding strain-specific responses and the long-term efficacy of these vaccines. This study assessed the Pfcsp genetic diversity, population structure and signatures of selection among parasites from areas of different malaria transmission intensities in Mainland Tanzania, to generate baseline data before the introduction of the malaria vaccines in the country. METHODS The analysis involved 589 whole genome sequences generated by and as part of the MalariaGEN Community Project. The samples were collected between 2013 and January 2015 from five regions of Mainland Tanzania: Morogoro and Tanga (Muheza) (moderate transmission areas), and Kagera (Muleba), Lindi (Nachingwea), and Kigoma (Ujiji) (high transmission areas). Wright's inbreeding coefficient (Fws), Wright's fixation index (FST), principal component analysis, nucleotide diversity, and Tajima's D were used to assess within-host parasite diversity, population structure and natural selection. RESULTS Based on Fws (< 0.95), there was high polyclonality (ranging from 69.23% in Nachingwea to 56.9% in Muheza). No population structure was detected in the Pfcsp gene in the five regions (mean FST = 0.0068). The average nucleotide diversity (π), nucleotide differentiation (K) and haplotype diversity (Hd) in the five regions were 4.19, 0.973 and 0.0035, respectively. The C-terminal region of Pfcsp showed high nucleotide diversity at Th2R and Th3R regions. Positive values for the Tajima's D were observed in the Th2R and Th3R regions consistent with balancing selection. The Pfcsp C-terminal sequences revealed 50 different haplotypes (H_1 to H_50), with only 2% of sequences matching the 3D7 strain haplotype (H_50). Conversely, with the NF54 strain, the Pfcsp C-terminal sequences revealed 49 different haplotypes (H_1 to H_49), with only 0.4% of the sequences matching the NF54 strain (Hap_49). CONCLUSIONS The findings demonstrate high diversity of the Pfcsp gene with limited population differentiation. The Pfcsp gene showed positive Tajima's D values, consistent with balancing selection for variants within Th2R and Th3R regions. The study observed differences between the intended haplotypes incorporated into the design of RTS,S and R21 vaccines and those present in natural parasite populations. Therefore, additional research is warranted, incorporating other regions and more recent data to comprehensively assess trends in genetic diversity within this important gene. Such insights will inform the choice of alleles to be included in the future vaccines.
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Affiliation(s)
- Beatus M Lyimo
- National Institute for Medical Research, Dar es Salaam, Tanzania.
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.
| | - Catherine Bakari
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | | | | | - Misago D Seth
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Dativa Pereus
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Zulfa I Shabani
- Dar Es Salaam University College of Education, University of Dar es Salaam, Dar es Salaam, Tanzania
| | - Ramadhan Moshi
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Ruth Boniface
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Celine I Mandara
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Rashid Madebe
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | | | | | - Deus S Ishengoma
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Harvard T.H Chan School of Public Health, Boston, MA, USA
- Faculty of Pharmaceutical Sciences, Monash University, Melbourne, Australia
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Lyimo BM, Bakari C, Popkin-Hall ZR, Giesbrecht DJ, Seth MD, Pereus D, Moshi R, Boniface R, Mandara CI, Madebe R, Juliano JJ, Bailey JA, Ishengoma DS. Genetic polymorphism and evidence of signatures of selection in the Plasmodium falciparum circumsporozoite protein gene in Tanzanian regions with different malaria endemicity. medRxiv 2024:2024.01.23.24301587. [PMID: 38343796 PMCID: PMC10854334 DOI: 10.1101/2024.01.23.24301587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Background In 2021 and 2023, the World Health Organization approved RTS, S/AS01 and R21/Matrix M malaria vaccines, respectively, for routine immunization of children in African countries with moderate to high transmission. These vaccines are made of Plasmodium falciparum circumsporozoite protein (Pfcsp) but polymorphisms in this gene raises concerns regarding strain-specific responses and the long-term efficacy of these vaccines. This study assessed the Pfcsp genetic diversity, population structure and signatures of selection among parasites from areas of different malaria transmission in mainland Tanzania, to generate baseline data before the introduction of the malaria vaccines in the country. Methods The analysis involved 589 whole genome sequences generated by and as part of the MalariaGEN Community Project. The samples were collected between 2013 and January 2015 from five regions of mainland Tanzania: Morogoro and Tanga (Muheza) (moderate transmission areas), and Kagera (Muleba), Lindi (Nachingwea), and Kigoma (Ujiji) (high transmission areas). Wright's inbreeding coefficient (Fws), Wright's fixation index (FST), principal component analysis, nucleotide diversity, and Tajima's D were used to assess within-host parasite diversity, population structure and natural selection. Results Based on Fws (< 0.95), there was high polyclonality (ranged from 69.23% in Nachingwea to 56.9% in Muheza). No population structure was detected in the Pfcsp gene in the five regions (mean FST= 0.0068). The average nucleotide diversity (π), nucleotide differentiation (K) and haplotype diversity (Hd) in the five regions were 4.19, 0.973 and 0.0035, respectively. The C-terminal region of Pfcsp showed high nucleotide diversity at Th2R and Th3R regions. Positive values for the Tajima's D were observed in the Th2R and Th3R regions consistent with balancing selection. The Pfcsp C-terminal sequences had 50 different haplotypes (H_1 to H_50) and only 2% of sequences matched the 3D7 strain haplotype (H_50). Conclusions The findings demonstrate high diversity of the Pfcsp gene with limited population differentiation. The Pfcsp gene showed positive Tajima's D values for parasite populations, consistent with balancing selection for variants within Th2R and Th3R regions. This data is consistent with other studies conducted across Africa and worldwide, which demonstrate low 3D7 haplotypes and little population structure. Therefore, additional research is warranted, incorporating other regions and more recent data to comprehensively assess trends in genetic diversity within this important gene. Such insights will inform the choice of alleles to be included in the future vaccines.
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Affiliation(s)
- Beatus M. Lyimo
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Catherine Bakari
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | | | | | - Misago D. Seth
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Dativa Pereus
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Ramadhan Moshi
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Ruth Boniface
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | | | - Rashid Madebe
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | | | | | - Deus S. Ishengoma
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Harvard T.H Chan School of Public Health, Boston, MA, USA
- Faculty of Pharmaceutical Sciences, Monash University, Melbourne, Australia
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Abstract
Malaria is a mosquito-borne disease caused by protozoan parasites of the genus Plasmodium. Despite significant declines in malaria-attributable morbidity and mortality over the last two decades, it remains a major public health burden in many countries. This underscores the critical need for improved strategies to prevent, treat and control malaria if we are to ultimately progress towards the eradication of this disease. Ideally, this will include the development and deployment of a highly effective malaria vaccine that is able to induce long-lasting protective immunity. There are many malaria vaccine candidates in development, with more than a dozen of these in clinical development. RTS,S/AS01 (also known as Mosquirix) is the most advanced malaria vaccine and was shown to have modest efficacy against clinical malaria in phase III trials in 5- to 17-month-old infants. Following pilot implementation trials, the World Health Organisation has recommended it for use in Africa in young children who are most at risk of infection with P. falciparum, the deadliest of the human malaria parasites. It is well recognised that more effective malaria vaccines are needed. In this review, we discuss malaria vaccine candidates that have progressed into clinical evaluation and highlight the most advanced candidates: Sanaria's irradiated sporozoite vaccine (PfSPZ Vaccine), the chemoattenuated sporozoite vaccine (PfSPZ-CVac), RTS,S/AS01 and the novel malaria vaccine candidate, R21, which displayed promising, high-level efficacy in a recent small phase IIb trial in Africa.
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Affiliation(s)
- Danielle I Stanisic
- Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, QLD, Australia.
| | - Michael F Good
- Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, QLD, Australia.
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Rajneesh, Tiwari R, Singh VK, Kumar A, Gupta RP, Singh AK, Gautam V, Kumar R. Advancements and Challenges in Developing Malaria Vaccines: Targeting Multiple Stages of the Parasite Life Cycle. ACS Infect Dis 2023; 9:1795-1814. [PMID: 37708228 DOI: 10.1021/acsinfecdis.3c00332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Malaria, caused by Plasmodium species, remains a major global health concern, causing millions of deaths annually. While the introduction of the RTS,S vaccine has shown promise, there is a pressing need for more effective vaccines due to the emergence of drug-resistant parasites and insecticide-resistant vectors. However, the complex life cycle and genetic diversity of the parasite, technical obstacles, limited funding, and the impact of the 2019 pandemic have hindered progress in malaria vaccine development. This review focuses on advancements in malaria vaccine development, particularly the ongoing clinical trials targeting antigens from different stages of the Plasmodium life cycle. Additionally, we discuss the rationale, strategies, and challenges associated with vaccine design, aiming to enhance the immune response and protective efficacy of vaccine candidates. A cost-effective and multistage vaccine could hold the key to controlling and eradicating malaria.
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Affiliation(s)
- Rajneesh
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Rahul Tiwari
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Vishal K Singh
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Awnish Kumar
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Rohit P Gupta
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
- Department of Applied Microbiology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Akhilesh K Singh
- Faculty of Dental Science, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Vibhav Gautam
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Rajiv Kumar
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
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Ren H, Jia W, Xie Y, Yu M, Chen Y. Adjuvant physiochemistry and advanced nanotechnology for vaccine development. Chem Soc Rev 2023; 52:5172-5254. [PMID: 37462107 DOI: 10.1039/d2cs00848c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
Vaccines comprising innovative adjuvants are rapidly reaching advanced translational stages, such as the authorized nanotechnology adjuvants in mRNA vaccines against COVID-19 worldwide, offering new strategies to effectively combat diseases threatening human health. Adjuvants are vital ingredients in vaccines, which can augment the degree, extensiveness, and longevity of antigen specific immune response. The advances in the modulation of physicochemical properties of nanoplatforms elevate the capability of adjuvants in initiating the innate immune system and adaptive immunity, offering immense potential for developing vaccines against hard-to-target infectious diseases and cancer. In this review, we provide an essential introduction of the basic principles of prophylactic and therapeutic vaccination, key roles of adjuvants in augmenting and shaping immunity to achieve desired outcomes and effectiveness, and the physiochemical properties and action mechanisms of clinically approved adjuvants for humans. We particularly focus on the preclinical and clinical progress of highly immunogenic emerging nanotechnology adjuvants formulated in vaccines for cancer treatment or infectious disease prevention. We deliberate on how the immune system can sense and respond to the physicochemical cues (e.g., chirality, deformability, solubility, topology, and chemical structures) of nanotechnology adjuvants incorporated in the vaccines. Finally, we propose possible strategies to accelerate the clinical implementation of nanotechnology adjuvanted vaccines, such as in-depth elucidation of nano-immuno interactions, antigen identification and optimization by the deployment of high-dimensional multiomics analysis approaches, encouraging close collaborations among scientists from different scientific disciplines and aggressive exploration of novel nanotechnologies.
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Affiliation(s)
- Hongze Ren
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
- School of Medicine, Shanghai University, Shanghai, 200444, P. R. China
| | - Wencong Jia
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
- School of Medicine, Shanghai University, Shanghai, 200444, P. R. China
| | - Yujie Xie
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
- School of Medicine, Shanghai University, Shanghai, 200444, P. R. China
| | - Meihua Yu
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
| | - Yu Chen
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
- School of Medicine, Shanghai University, Shanghai, 200444, P. R. China
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El-Moamly AA, El-Sweify MA. Malaria vaccines: the 60-year journey of hope and final success-lessons learned and future prospects. Trop Med Health 2023; 51:29. [PMID: 37198702 DOI: 10.1186/s41182-023-00516-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 04/18/2023] [Indexed: 05/19/2023] Open
Abstract
BACKGROUND The world has made great strides towards beating malaria, although about half of the world population is still exposed to the risk of contracting malaria. Developing an effective malaria vaccine was a huge challenge for medical science. In 2021 the World Health Organization (WHO) approved the first malaria vaccine, RTS,S/AS01 vaccine (Mosquirix™), for widespread use. This review highlights the history of development, and the different approaches and types of malaria vaccines, and the literature to date. It covers the developmental stages of RTS,S/AS01 and recommends steps for its deployment. The review explores other potential vaccine candidates and their status, and suggests options for their further development. It also recommends future roles for vaccines in eradicating malaria. Questions remain on how RTS,S vaccine will work in widespread use and how it can best be utilized to benefit vulnerable communities. CONCLUSION Malaria vaccines have been in development for almost 60 years. The RTS,S/AS01 vaccine has now been approved, but cannot be a stand-alone solution. Development should continue on promising candidates such as R21, PfSPZ and P. vivax vaccines. Multi-component vaccines may be a useful addition to other malaria control techniques in achieving eradication of malaria.
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Affiliation(s)
- Amal A El-Moamly
- Department of Medical Parasitology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt.
| | - Mohamed A El-Sweify
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
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Oludada OE, Costa G, Burn Aschner C, Obraztsova AS, Prieto K, Canetta C, Hoffman SL, Kremsner PG, Mordmüller B, Murugan R, Julien JP, Levashina EA, Wardemann H. Molecular and functional properties of human Plasmodium falciparum CSP C-terminus antibodies. EMBO Mol Med 2023:e17454. [PMID: 37082831 DOI: 10.15252/emmm.202317454] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/11/2023] [Accepted: 03/23/2023] [Indexed: 04/22/2023] Open
Abstract
Human monoclonal antibodies (mAbs) against the central repeat and junction domain of Plasmodium falciparum circumsporozoite protein (PfCSP) have been studied extensively to guide malaria vaccine design compared to antibodies against the PfCSP C terminus. Here, we describe the molecular characteristics and protective potential of 73 germline and mutated human mAbs against the highly immunogenic PfCSP C-terminal domain. Two mAbs recognized linear epitopes in the C-terminal linker with sequence similarity to repeat and junction motifs, whereas all others targeted conformational epitopes in the α-thrombospondin repeat (α-TSR) domain. Specificity for the polymorphic Th2R/Th3R but not the conserved RII+/CS.T3 region in the α-TSR was associated with IGHV3-21/IGVL3-21 or IGLV3-1 gene usage. Although the C terminus specific mAbs showed signs of more efficient affinity maturation and class-switching compared to anti-repeat mAbs, live sporozoite binding and inhibitory activity was limited to a single C-linker reactive mAb with cross-reactivity to the central repeat and junction. The data provide novel insights in the human anti-C-linker and anti-α-TSR antibody response that support exclusion of the PfCSP C terminus from malaria vaccine designs.
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Affiliation(s)
- Opeyemi Ernest Oludada
- B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
- Biosciences Faculty, University of Heidelberg, Germany
| | - Giulia Costa
- Vector Biology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
| | | | - Anna S Obraztsova
- B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
- Biosciences Faculty, University of Heidelberg, Germany
| | - Katherine Prieto
- The Hospital for Sick Children Research Institute, Toronto, ON, Canada
| | - Caterina Canetta
- B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
| | | | - Peter G Kremsner
- Institute of Tropical Medicine, Tübingen, Germany
- Centre de Recherches de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institute of Tropical Medicine, Tübingen, Germany
- Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rajagopal Murugan
- B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
| | - Jean-Philippe Julien
- The Hospital for Sick Children Research Institute, Toronto, ON, Canada
- Departments of Biochemistry and Immunology, University of Toronto, Toronto, ON, Canada
| | - Elena A Levashina
- Vector Biology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Hedda Wardemann
- B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
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Yihunie W, Kebede B, Tegegne BA, Getachew M, Abebe D, Aschale Y, Belew H, Bahiru B. Systematic Review of Safety of RTS,S with AS01 and AS02 Adjuvant Systems Using Data from Randomized Controlled Trials in Infants, Children, and Adults. Clin Pharmacol 2023; 15:21-32. [PMID: 36941908 PMCID: PMC10024506 DOI: 10.2147/cpaa.s400155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 03/07/2023] [Indexed: 03/16/2023] Open
Abstract
Background Emergence of antimalarial drugs and insecticides resistance alarms scientists to develop a safe and effective malaria vaccine. A pre-erythrocytic malaria vaccine called RTS,S has made great strides. Aim The review was aimed to assess the safety of the candidate malaria vaccine RTS,S with AS01 and AS02 adjuvants using data from Phase I-III randomized controlled clinical trials (RCTs). Methods This systematic review was conducted based on PRISMA 2020. Regardless of time of publication year, all articles related with safety of RTS,S, RCTs published in the English language were included in the study. The last search of databases, and registry was conducted on 30 May, 2022. Pubmed, Google Scholar, Cochrane Library, Wiley Online Library, and Clinical trials.gov were thoroughly searched for accessible RCTs on the safety of RTS,S malaria vaccine. The studies were screened in three steps: duplicate removal, title and abstract screening, and full-text review. The included studies' bias risk was assessed using the Cochrane risk of bias tool for RCTs. This systematic review is registered at Prospero (registration number: CRD42021285888). The qualitative descriptive findings from the included published studies were reported stratified by clinical trial phases. Findings A total of thirty-five eligible safety studies were identified. Injection site pain and swelling, febrile convulsion, fever, headache, meningitis, fatigue, gastroenteritis, myalgia, pneumonia, reactogenicity, and anemia were the most commonly reported adverse events. Despite few clinical trials reported serious adverse events, none of them were related to vaccination. Conclusion Most of the adverse events observed from RTS,S/AS01 and RTS,S/AS02 malaria vaccines were reported in the control group and shared by other vaccines. Hence, the authors concluded that both RTS,S/AS01 and RTS,S/AS02 malaria vaccines are safe.
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Affiliation(s)
- Wubetu Yihunie
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Bekalu Kebede
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Bantayehu Addis Tegegne
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Melese Getachew
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Dehnnet Abebe
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Yibeltal Aschale
- Department of Medical Laboratory Science, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Habtamu Belew
- Department of Medical Laboratory Science, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Bereket Bahiru
- Department of Pharmacy, College of Medicine and health sciences, Bahir Dar University, Bahir Dar, Ethiopia
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Mariano RMDS, Gonçalves AAM, de Oliveira DS, Ribeiro HS, Pereira DFS, Santos IS, Lair DF, da Silva AV, Galdino AS, Chávez-Fumagalli MA, da Silveira-Lemos D, Dutra WO, Giunchetti RC. A Review of Major Patents on Potential Malaria Vaccine Targets. Pathogens 2023; 12:pathogens12020247. [PMID: 36839519 PMCID: PMC9959516 DOI: 10.3390/pathogens12020247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
Malaria is a parasitic infection that is a great public health concern and is responsible for high mortality rates worldwide. Different strategies have been employed to improve disease control, demonstrating the ineffectiveness of controlling vectors, and parasite resistance to antimalarial drugs requires the development of an effective preventive vaccine. There are countless challenges to the development of such a vaccine directly related to the parasite's complex life cycle. After more than four decades of basic research and clinical trials, the World Health Organization (WHO) has recommended the pre-erythrocytic Plasmodium falciparum (RTS, S) malaria vaccine for widespread use among children living in malaria-endemic areas. However, there is a consensus that major improvements are needed to develop a vaccine with a greater epidemiological impact in endemic areas. This review discusses novel strategies for malaria vaccine design taking the target stages within the parasite cycle into account. The design of the multi-component vaccine shows considerable potential, especially as it involves transmission-blocking vaccines (TBVs) that eliminate the parasite's replication towards sporozoite stage parasites during a blood meal of female anopheline mosquitoes. Significant improvements have been made but additional efforts to achieve an efficient vaccine are required to improve control measures. Different strategies have been employed, thus demonstrating the ineffectiveness in controlling vectors, and parasite resistance to antimalarial drugs requires the development of a preventive vaccine. Despite having a vaccine in an advanced stage of development, such as the RTS, S malaria vaccine, the search for an effective vaccine against malaria is far from over. This review discusses novel strategies for malaria vaccine design taking into account the target stages within the parasite's life cycle.
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Affiliation(s)
- Reysla Maria da Silveira Mariano
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Ana Alice Maia Gonçalves
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Diana Souza de Oliveira
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Helen Silva Ribeiro
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Diogo Fonseca Soares Pereira
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Ingrid Soares Santos
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Daniel Ferreira Lair
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Augusto Ventura da Silva
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Alexsandro Sobreira Galdino
- Laboratory of Biotechnology of Microorganisms, Federal University of São João Del-Rei, Divinópolis CEP 35501-296, MG, Brazil
| | - Miguel Angel Chávez-Fumagalli
- Computational Biology and Chemistry Research Group, Vicerrectorado de Investigación, Universidad Católica de Santa María, Urb. San José S/N, Arequipa 04000, Peru
| | - Denise da Silveira-Lemos
- Campus Jaraguá, University José of Rosário Vellano, UNIFENAS, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Walderez Ornelas Dutra
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
| | - Rodolfo Cordeiro Giunchetti
- Laboratory of Biology of Cell Interactions, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte CEP 31270-901, MG, Brazil
- Correspondence: or ; Tel.: +55-31-3409-3003
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Ngwa CJ, Stratmann R, Musabyimana JP, Pannen K, Schöbel JH, Frings M, Schiffers I, Quaranta C, Koschmieder S, Chatain N, Pradel G, Bolm C. Evaluation of Chiral Organosulfur Compounds on Their Activity against the Malaria Parasite Plasmodium falciparum. Trop Med Infect Dis 2022; 7:tropicalmed7120416. [PMID: 36548671 PMCID: PMC9785921 DOI: 10.3390/tropicalmed7120416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/21/2022] [Accepted: 11/30/2022] [Indexed: 12/09/2022] Open
Abstract
Malaria is one of the deadliest tropical diseases, especially causing havoc in children under the age of five in Africa. Although the disease is treatable, the rapid development of drug resistant parasites against frontline drugs requires the search for novel antimalarials. In this study, we tested a series of organosulfur compounds from our internal library for their antiplasmodial effect against Plasmodium falciparum asexual and sexual blood stages. Some active compounds were also obtained in enantiomerically pure form and tested individually against asexual blood stages of the parasite to compare their activity. Out of the 23 tested compounds, 7 compounds (1, 2, 5, 9, 15, 16, and 17) exhibited high antimalarial activity, with IC50 values in the range from 2.2 ± 0.64 to 5.2 ± 1.95 µM, while the other compounds showed moderate to very low activity. The most active compounds also exhibited high activity against the chloroquine-resistant strain, reduced gametocyte development and were not toxic to non-infected red blood cells and Hela cells, as well as the hematopoietic HEL cell line at concentrations below 50 µM. To determine if the enantiomers of the active compounds display different antimalarial activity, enantiomers of two of the active compounds were separated and their antimalarial activity compared. The results show a higher activity of the (-) enantiomers as compared to their (+) counterparts. Our combined data indicate that organosulfur compounds could be exploited as antimalarial drugs and enantiomers of the active compounds may represent a good starting point for the design of novel drugs to target malaria.
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Affiliation(s)
- Che Julius Ngwa
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, 52074 Aachen, Germany
- Correspondence: (C.J.N.); (C.B.)
| | - Rabea Stratmann
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, 52074 Aachen, Germany
| | - Jean Pierre Musabyimana
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, 52074 Aachen, Germany
| | - Kristina Pannen
- Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany
- Center for Integrated Oncology, Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany
| | - Jan-Hendrik Schöbel
- Institute of Organic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Marcus Frings
- Institute of Organic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Ingo Schiffers
- Institute of Organic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Calogero Quaranta
- Institute of Organic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Steffen Koschmieder
- Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany
- Center for Integrated Oncology, Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany
| | - Nicolas Chatain
- Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany
- Center for Integrated Oncology, Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, 52074 Aachen, Germany
| | - Carsten Bolm
- Institute of Organic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- Correspondence: (C.J.N.); (C.B.)
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Abstract
The complex Plasmodium life cycle offers different vaccine approaches with distinct parasitological and clinical effects. The approaches and their rationales were established decades ago: vaccines targeting pre-erythrocytic (sporozoite and liver-stage) parasites prevent infection, those to blood-stage parasites reduce disease, and those to sexual-stage parasites or mosquito vector reduce transmission and eliminate malaria through herd immunity. The pre-erythrocytic RTS,S vaccine (Mosquirix, GlaskoSmithKline (GSK)), recommended by WHO in 2021, reduces clinical malaria in children. Knowledge of parasite biology, host-parasite interactions, and immune mechanisms is informing new concepts to improve on RTS,S and to target other parasite stages. This review emphasizes vaccine approaches and candidates currently in the clinic or likely to enter clinical testing soon.
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Affiliation(s)
- Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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Kayentao K, Ongoiba A, Preston AC, Healy SA, Doumbo S, Doumtabe D, Traore A, Traore H, Djiguiba A, Li S, Peterson ME, Telscher S, Idris AH, Kisalu NK, Carlton K, Serebryannyy L, Narpala S, McDermott AB, Gaudinski M, Traore S, Cisse H, Keita M, Skinner J, Hu Z, Zéguimé A, Ouattara A, Doucoure M, Dolo A, Djimdé A, Traore B, Seder RA, Crompton PD. Safety and Efficacy of a Monoclonal Antibody against Malaria in Mali. N Engl J Med 2022; 387:1833-1842. [PMID: 36317783 PMCID: PMC9881676 DOI: 10.1056/nejmoa2206966] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND CIS43LS is a monoclonal antibody that was shown to protect against controlled Plasmodium falciparum infection in a phase 1 clinical trial. Whether a monoclonal antibody can prevent P. falciparum infection in a region in which the infection is endemic is unknown. METHODS We conducted a phase 2 trial to assess the safety and efficacy of a single intravenous infusion of CIS43LS against P. falciparum infection in healthy adults in Mali over a 6-month malaria season. In Part A, safety was assessed at three escalating dose levels. In Part B, participants were randomly assigned (in a 1:1:1 ratio) to receive 10 mg of CIS43LS per kilogram of body weight, 40 mg of CIS43LS per kilogram, or placebo. The primary efficacy end point, assessed in a time-to-event analysis, was the first P. falciparum infection detected on blood-smear examination, which was performed at least every 2 weeks for 24 weeks. At enrollment, all the participants received artemether-lumefantrine to clear possible P. falciparum infection. RESULTS In Part B, 330 adults underwent randomization; 110 were assigned to each trial group. The risk of moderate headache was 3.3 times as high with 40 mg of CIS43LS per kilogram as with placebo. P. falciparum infections were detected on blood-smear examination in 39 participants (35.5%) who received 10 mg of CIS43LS per kilogram, 20 (18.2%) who received 40 mg of CIS43LS per kilogram, and 86 (78.2%) who received placebo. At 6 months, the efficacy of 40 mg of CIS43LS per kilogram as compared with placebo was 88.2% (adjusted 95% confidence interval [CI], 79.3 to 93.3; P<0.001), and the efficacy of 10 mg of CIS43LS per kilogram as compared with placebo was 75.0% (adjusted 95% CI, 61.0 to 84.0; P<0.001). CONCLUSIONS CIS43LS was protective against P. falciparum infection over a 6-month malaria season in Mali without evident safety concerns. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT04329104.).
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Affiliation(s)
- Kassoum Kayentao
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Aissata Ongoiba
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Anne C Preston
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Sara A Healy
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Safiatou Doumbo
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Didier Doumtabe
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Abdrahamane Traore
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Hamadi Traore
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Adama Djiguiba
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Shanping Li
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Mary E Peterson
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Shinyi Telscher
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Azza H Idris
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Neville K Kisalu
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Kevin Carlton
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Leonid Serebryannyy
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Sandeep Narpala
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Adrian B McDermott
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Martin Gaudinski
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Siriman Traore
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Hamidou Cisse
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Mamadou Keita
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Jeff Skinner
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Zonghui Hu
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Amatigué Zéguimé
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Adama Ouattara
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - M'Bouye Doucoure
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Amagana Dolo
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Abdoulaye Djimdé
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Boubacar Traore
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Robert A Seder
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
| | - Peter D Crompton
- From the Malaria Research and Training Center, Mali International Center for Excellence in Research, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali (K.K., A. Ongoiba, S.D., D.D., A.T., H.T., A. Djiguiba, S. Traore, H.C., M.K., A.Z., A. Ouattara, M.D., A. Dolo, A. Djimdé, B.T.); and the Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, Division of Intramural Research (A.C.P., S.A.H., S.L., M.E.P., J.S., P.D.C.), and the Biostatistics Research Branch, Division of Clinical Research (Z.H.), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, and the Vaccine Research Center, NIAID, NIH, Bethesda (S. Telscher, A.H.I., N.K.K., K.C., L.S., S.N., A.B.M., M.G., R.A.S.) - all in Maryland
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Dey S, Kaur H, Mazumder M, Brodsky E. Analysis of gene expression profiles to study malaria vaccine dose efficacy and immune response modulation. Genomics Inform 2022; 20:e32. [PMID: 36239109 PMCID: PMC9576474 DOI: 10.5808/gi.22049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2002] [Accepted: 09/04/2022] [Indexed: 11/20/2022] Open
Abstract
Malaria is a life-threatening disease, and Africa is still one of the most affected endemic regions despite years of policy to limit infection and transmission rates. Further, studies into the variable efficacy of the vaccine are needed to provide a better understanding of protective immunity. Thus, the current study is designed to delineate the effect of each dose of vaccine on the transcriptional profiles of subjects to determine its efficacy and understand the molecular mechanisms underlying the protection this vaccine provides. Here, we used gene expression profiles of pre and post-vaccination patients after various doses of RTS,S based on samples collected from the Gene Expression Omnibus datasets. Subsequently, differential gene expression analysis using edgeR revealed the significantly (false discovery rate < 0.005) 158 downregulated and 61 upregulated genes between control vs. controlled human malaria infection samples. Further, enrichment analysis of significant genes delineated the involvement of CCL8, CXCL10, CXCL11, XCR1, CSF3, IFNB1, IFNE, IL12B, IL22, IL6, IL27, etc., genes which found to be upregulated after earlier doses but downregulated after the 3rd dose in cytokine-chemokine pathways. Notably, we identified 13 cytokine genes whose expression significantly varied during three doses. Eventually, these findings give insight into the dual role of cytokine responses in malaria pathogenesis. The variations in their expression patterns after various doses of vaccination are linked to the protection as it decreases the severe inflammatory effects in malaria patients. This study will be helpful in designing a better vaccine against malaria and understanding the functions of cytokine response as well.
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Affiliation(s)
- Supantha Dey
- Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka 1000, Bangladesh
- Pine Biotech, New Orleans, LA 70112, USA
- Corresponding author: ,
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17
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Sagara I, Zongo I, Cairns M, Yerbanga RS, Mahamar A, Nikièma F, Tapily A, Sompougdou F, Diarra M, Zoungrana C, Issiaka D, Haro A, Sanogo K, Aziz Sienou A, Kaya M, Traore S, Thera I, Diarra K, Dolo A, Kuepfer I, Snell P, Milligan P, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Ouedraogo JB, Dicko A, Chandramohan D, Greenwood B. The Anti-Circumsporozoite Antibody Response of Children to Seasonal Vaccination With the RTS,S/AS01E Malaria Vaccine. Clin Infect Dis 2022; 75:613-622. [PMID: 34894221 PMCID: PMC9464075 DOI: 10.1093/cid/ciab1017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND A trial in African children showed that combining seasonal vaccination with the RTS,S/AS01E vaccine with seasonal malaria chemoprevention reduced the incidence of uncomplicated and severe malaria compared with either intervention given alone. Here, we report on the anti-circumsporozoite antibody response to seasonal RTS,S/AS01E vaccination in children in this trial. METHODS Sera from a randomly selected subset of children collected before and 1 month after 3 priming doses of RTS,S/AS01E and before and 1 month after 2 seasonal booster doses were tested for anti-circumsporozoite antibodies using enzyme-linked immunosorbent assay. The association between post-vaccination antibody titer and incidence of malaria was explored. RESULTS A strong anti-circumsporozoite antibody response to 3 priming doses of RTS,S/AS01E was seen (geometric mean titer, 368.9 enzyme-linked immunosorbent assay units/mL), but titers fell prior to the first booster dose. A strong antibody response to an annual, pre-malaria transmission season booster dose was observed, but this was lower than after the primary vaccination series and lower after the second than after the first booster dose (ratio of geometric mean rise, 0.66; 95% confidence interval [CI], .57-.77). Children whose antibody response was in the upper tercile post-vaccination had a lower incidence of malaria during the following year than children in the lowest tercile (hazard ratio, 0.43; 95% CI, .28-.66). CONCLUSIONS Seasonal vaccination with RTS,S/AS01E induced a strong booster antibody response that was lower after the second than after the first booster dose. The diminished antibody response to the second booster dose was not associated with diminished efficacy. CLINICAL TRIALS REGISTRATION NCT03143218.
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Affiliation(s)
| | | | - Matthew Cairns
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Almahamoudou Mahamar
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Frédéric Nikièma
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Amadou Tapily
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - Modibo Diarra
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Charles Zoungrana
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Djibrilla Issiaka
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Alassane Haro
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Koualy Sanogo
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Abdoul Aziz Sienou
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Mahamadou Kaya
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Seydou Traore
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Ismaila Thera
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Kalifa Diarra
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Amagana Dolo
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Irene Kuepfer
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Paul Snell
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Paul Milligan
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Abdoulaye Djimde
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - Alassane Dicko
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - Brian Greenwood
- Correspondence: B. Greenwood, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel St., London WC1E 7HT, UK ()
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He ZQ, Zhang QQ, Wang D, Hu YB, Zhou RM, Qian D, Yang CY, Lu DL, Li SH, Liu Y, Zhang HW. Genetic polymorphism of circumsporozoite protein of Plasmodium falciparum among Chinese migrant workers returning from Africa to Henan Province. Malar J 2022; 21:248. [PMID: 36030242 PMCID: PMC9419638 DOI: 10.1186/s12936-022-04275-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 08/18/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Plasmodium falciparum malaria is recognized as a major global public health problem. The malaria vaccine was important because the case fatality rate of falciparum malaria was high. Plasmodium falciparum circumsporozoite protein (PfCSP) is one of the potential vaccine candidates, but the genetic polymorphism of PfCSP raises concerns regarding the efficacy of the vaccine. This study aimed to investigate the genetic polymorphism of PfCSP and provide data for the improvement of PfCSP-based vaccine (RTS,S malaria vaccine). METHODS Blood samples were collected from 287 Chinese migrant workers who were infected with P. falciparum and returning from Africa to Henan Province during 2016-2018. The Pfcsp genes were analysed to estimate the genetic diversity of this parasite. RESULTS The results showed that there were two mutations at the N-terminus of imported Pfcsp in Henan Province, including insertion amino acids (58.71%, 118/201) and A → G (38.81%, 78/201). The number of repeats of tetrapeptide motifs (NANP/NVDP/NPNP/NVDA) in the central repeat region ranged mainly from 39 to 42 (97.51%, 196/201). A total of 14 nonsynonymous amino acid changes were found at the C-terminus. The average nucleotide difference (K) of imported Pfcsp in Henan Province was 5.719, and the haplotype diversity (Hd) was 0.964 ± 0.004. The estimated value of dN-dS was 0.047, indicating that the region may be affected by positive natural selection. The minimum number of recombination events (Rm) of imported Pfcsp in Henan Province was close to that in Africa. The analysis of genetic differentiation showed that there may be moderate differentiation between East Africa and North Africa (Fst = 0.06484), and the levels of differentiation in the other regions were very small (Fst < 0.05). CONCLUSIONS The N-terminus of Pfcsp was relatively conserved, and the central repeat region and the Th2R and Th3R regions of the C-terminus were highly polymorphic. The gene polymorphism pattern among Chinese migrant workers returning from Africa to Henan Province was consistent with that in Africa. The geographical pattern of population differentiation and the evidence of natural selection and gene recombination suggested that the effect of polymorphism on the efficacy of PfCSP-based vaccines should be considered.
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Affiliation(s)
- Zhi-Quan He
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Qun-Qun Zhang
- Fengtai District Center for Disease Control and Prevention, Beijing, China
| | - Dan Wang
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Ya-Bo Hu
- College of Public Health, Zhengzhou University, Zhengzhou, China
| | - Rui-Min Zhou
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Dan Qian
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Cheng-Yun Yang
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - De-Ling Lu
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Su-Hua Li
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Ying Liu
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China. .,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China.
| | - Hong-Wei Zhang
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China. .,Henan Key Laboratory of Pathogenic Microorganisms, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China.
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Budiman C, Razak RA, Unggit ARA, Razali R, Suzery M, Mokhtar RAM, Lee PC, Utomo DH. Catalytic Properties of Caseinolytic Protease Subunit of Plasmodium knowlesi and Its Inhibition by a Member of δ-Lactone, Hyptolide. Molecules 2022; 27:3787. [PMID: 35744912 DOI: 10.3390/molecules27123787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/05/2022] [Accepted: 06/08/2022] [Indexed: 11/17/2022]
Abstract
The caseinolytic protease (Clp) system plays an essential role in the protein homeostasis of the malaria parasite, particularly at the stage of apicoplast development. The inhibition of this protein is known to have a lethal effect on the parasite and is therefore considered an interesting avenue for antimalaria drugs discovery. The catalytic activity of the Clp system is modulated by its proteolytic subunit (ClpP), which belongs to the serine protease family member and is therefore extensively studied for further inhibitors development. Among many inhibitors, the group of β-lactone is known to be a specific inhibitor for ClpP. Nevertheless, other groups of lactones have never been studied. This study aims to characterize the catalytic properties of ClpP of Plasmodium knowlesi (Pk-ClpP) and the inhibition properties of a δ-lactone hyptolide against this protein. Accordingly, a codon-optimized synthetic gene encoding Pk-ClpP was expressed in Escherichia coli BL21(DE3) and purified under a single step of Ni2+-affinity chromatography, yielding a 2.20 mg from 1 L culture. Meanwhile, size-exclusion chromatography indicated that Pk-ClpP migrated primarily as homoheptameric with a size of 205 kDa. The specific activity of pure Pk-ClpP was 0.73 U µg-1, with a catalytic efficiency kcat/KM of 0.05 µM-1 s-1, with optimum temperature and pH of 50 °C and 7.0-7.5, respectively. Interestingly, hyptolide, a member of δ-lactone, was shown to inhibit Pk-ClpP with an IC50 value of 17.36 ± 1.44 nM. Structural homology modelling, secondary structure prediction, and far-UV CD spectra revealed that helical structures dominate this protein. In addition, the structural homology modeling showed that this protein forms a barrel-shaped homoheptamer. Docking simulation revealed that the inhibition was found to be a competitive inhibition in which hyptolide was able to dock into the catalytic site and block the substrate. The competitiveness of hyptolide is due to the higher binding affinity of this molecule than the substrate.
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20
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Wahl I, Obraztsova AS, Puchan J, Hundsdorfer R, Chakravarty S, Sim BKL, Hoffman SL, Kremsner PG, Mordmüller B, Wardemann H. Clonal evolution and TCR specificity of the human T FH cell response to Plasmodium falciparum CSP. Sci Immunol 2022; 7:eabm9644. [PMID: 35687696 DOI: 10.1126/sciimmunol.abm9644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
T follicular helper (TFH) cells play a crucial role in the development of long-lived, high-quality B cell responses after infection and vaccination. However, little is known about how antigen-specific TFH cells clonally evolve in response to complex pathogens and what guides the targeting of different epitopes. Here, we assessed the cell phenotype, clonal dynamics, and T cell receptor (TCR) specificity of human circulating TFH (cTFH) cells during successive malaria immunizations with radiation-attenuated Plasmodium falciparum (Pf) sporozoites. Repeated parasite exposures induced a dynamic, polyclonal cTFH response with high frequency of cells specific to a small number of epitopes in Pf circumsporozoite protein (PfCSP), the primary sporozoite surface protein and well-defined vaccine target. Human leukocyte antigen (HLA) restrictions and differences in TCR generation probability were associated with differences in the epitope targeting frequency and indicated the potential of amino acids 311 to 333 in the Th2R/T* region as a T cell supertope. But most of vaccine-induced anti-amino acid 311 to 333 TCRs, including convergent TCRs with high sequence similarity, failed to tolerate natural polymorphisms in their target peptide sequence, thus demonstrating that the TFH cell response was limited to the vaccine strain. These data suggest that the high parasite diversity in endemic areas will limit boosting of the vaccine-induced TFH cell response by natural infections. Our findings may guide the further design of PfCSP-based malaria vaccines able to induce potent T helper cell responses for broad, long-lasting antibody responses.
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Affiliation(s)
- Ilka Wahl
- Division of B Cell Immunology, German Cancer Research Center, Heidelberg, Germany.,Biosciences Faculty, University of Heidelberg, Heidelberg, Germany
| | - Anna S Obraztsova
- Division of B Cell Immunology, German Cancer Research Center, Heidelberg, Germany.,Biosciences Faculty, University of Heidelberg, Heidelberg, Germany
| | - Julia Puchan
- Division of B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
| | - Rebecca Hundsdorfer
- Division of B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
| | | | | | | | - Peter G Kremsner
- Institute of Tropical Medicine and German Center for Infection Research, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institute of Tropical Medicine and German Center for Infection Research, University of Tübingen, Tübingen, Germany.,Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Hedda Wardemann
- Division of B Cell Immunology, German Cancer Research Center, Heidelberg, Germany
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Sissoko MS, Healy SA, Katile A, Zaidi I, Hu Z, Kamate B, Samake Y, Sissoko K, Mwakingwe-Omari A, Lane J, Imeru A, Mohan R, Thera I, Guindo CO, Dolo A, Niare K, Koïta F, Niangaly A, Rausch KM, Zeguime A, Guindo MA, Bah A, Abebe Y, James ER, Manoj A, Murshedkar T, Kc N, Sim BKL, Billingsley PF, Richie TL, Hoffman SL, Doumbo O, Duffy PE. Safety and efficacy of a three-dose regimen of Plasmodium falciparum sporozoite vaccine in adults during an intense malaria transmission season in Mali: a randomised, controlled phase 1 trial. Lancet Infect Dis 2022; 22:377-89. [PMID: 34801112 DOI: 10.1016/S1473-3099(21)00332-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/28/2021] [Accepted: 05/28/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND WHO recently approved a partially effective vaccine that reduces clinical malaria in children, but increased vaccine activity is required to pursue malaria elimination. A phase 1 clinical trial was done in Mali, west Africa, to assess the safety, immunogenicity, and protective efficacy of a three-dose regimen of Plasmodium falciparum sporozoite (PfSPZ) Vaccine (a metabolically active, non-replicating, whole malaria sporozoite vaccine) against homologous controlled human malaria infection (CHMI) and natural P falciparum infection. METHODS We recruited healthy non-pregnant adults aged 18-50 years in Donéguébougou, Mali, and surrounding villages (Banambani, Toubana, Torodo, Sirababougou, Zorokoro) for an open-label, dose-escalation pilot study and, thereafter, a randomised, double-blind, placebo-controlled main trial. Pilot study participants were enrolled on an as-available basis to one group of CHMI infectivity controls and three staggered vaccine groups receiving: one dose of 4·5 × 105, one dose of 9 × 105, or three doses of 1·8 × 106 PfSPZ via direct venous inoculation at approximately 8 week intervals, followed by homologous CHMI 5 weeks later with infectious PfSPZ by direct venous inoculation (PfSPZ Challenge). Main cohort participants were stratified by village and randomly assigned (1:1) to receive three doses of 1·8 × 106 PfSPZ or normal saline at 1, 13, and 19 week intervals using permuted block design by the study statistician. The primary outcome was safety and tolerability of at least one vaccine dose; the secondary outcome was vaccine efficacy against homologous PfSPZ CHMI (pilot study) or against naturally transmitted P falciparum infection (main study) measured by thick blood smear. Combined artesunate and amodiaquine was administered to eliminate pre-existing parasitaemia. Outcomes were analysed by modified intention to treat (mITT; including all participants who received at least one dose of investigational product; safety and vaccine efficacy) and per protocol (vaccine efficacy). This trial is registered with ClinicalTrials.gov, number NCT02627456. FINDINGS Between Dec 20, 2015, and April 30, 2016, we enrolled 56 participants into the pilot study (five received the 4·5 × 105 dose, five received 9 × 105, 30 received 1·8 × 106, 15 were CHMI controls, and one withdrew before vaccination) and 120 participants into the main study cohort with 60 participants assigned PfSPZ Vaccine and 60 placebo in the main study. Adverse events and laboratory abnormalities post-vaccination in all dosing groups were few, mainly mild, and did not differ significantly between vaccine groups (all p>0·05). Unexpected severe transaminitis occured in four participants: one participant in pilot phase that received 1·8 × 106 PfSPZ Vaccine, one participant in main phase that received 1·8 × 106 PfSPZ Vaccine, and two participants in the main phase placebo group. During PfSPZ CHMI, approximately 5 weeks after the third dose of 1·8 × 106 PfSPZ, none of 29 vaccinees and one of 15 controls became positive on thick blood smear; subsequent post-hoc PCR analysis for submicroscopic blood stage infections detected P falciparum parasites in none of the 29 vaccine recipients and eight of 15 controls during CHMI. In the main trial, 32 (58%) of 55 vaccine recipients and 42 (78%) of 54 controls became positive on thick blood smear during 24-week surveillance after vaccination. Vaccine efficacy (1-hazard ratio) was 0·51 per protocol (95% CI 0·20-0·70; log-rank p=0·0042) and 0·39 by mITT (0·04-0·62; p=0·033); vaccine efficacy (1-risk ratio) was 0·24 per-protocol (0·02-0·41; p=0·031) and 0·22 mITT (0·01-0·39; p=0·041). INTERPRETATION A three-dose regimen of PfSPZ Vaccine was safe, well tolerated, and conferred 51% vaccine efficacy against intense natural P falciparum transmission, similar to 52% vaccine efficacy reported for a five-dose regimen in a previous trial. FUNDING US National Institute of Allergy and Infectious Diseases, National Institutes of Health, Sanaria. TRANSLATION For the French translation of the abstract see Supplementary Materials section.
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23
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Mohamed NS, AbdElbagi H, Elsadig AR, Ahmed AE, Mohammed YO, Elssir LT, Elnour MAB, Ali Y, Ali MS, Altahir O, Abubakr M, Siddig EE, Ahmed A, Omer RA. Assessment of genetic diversity of Plasmodium falciparum circumsporozoite protein in Sudan: the RTS,S leading malaria vaccine candidate. Malar J 2021; 20:436. [PMID: 34758827 PMCID: PMC8579544 DOI: 10.1186/s12936-021-03971-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 11/01/2021] [Indexed: 11/20/2022] Open
Abstract
Background The currently used malaria vaccine, RTS,S, is designed based on the Plasmodium falciparum circumsporozoite protein (PfCSP). The pfcsp gene, besides having different polymorphic patterns, can vary between P. falciparum isolates due to geographical origin and host immune response. Such aspects are essential when considering the deployment of the RTS,S vaccine in a certain region. Therefore, this study assessed the genetic diversity of P. falciparum in Sudan based on the pfcsp gene by investigating the diversity at the N-terminal, central repeat, and the C-terminal regions. Methods A cross-sectional molecular study was conducted; P. falciparum isolates were collected from different health centres in Khartoum State between January and December 2019. During the study period, a total of 261 febrile patients were recruited. Malaria diagnosis was made by expert microscopists using Giemsa-stained thick and thin blood films. DNA samples were examined by the semi-nested polymerase chain reaction (PCR). Single clonal infection of the confirmed P. falciparum cases, were used to amplify the pfcsp gene. The amplified amplicons of pfcsp have been sequenced using the Sanger dideoxy method. The obtained sequences of pfcsp nucleotide diversity parameters including the numbers of haplotypes (Hap), haplotypes diversity (Hapd), the average number of nucleotide differences between two sequences (p), and the numbers of segregating sites (S) were obtained. The haplotype networks were constructed using the online tcsBU software. Natural selection theory was also tested on pfcsp using Fuand Li’s D, Fuand Li’s F statistics, and Tajima’s D test using DnaSP. Results In comparison with the different pfcsp reference strains, the Sudanese isolates showed high similarity with other African isolates. The results of the N-terminal region showed the presence of 2 different haplotypes with a Hapd of 0.425 ± 0.00727. The presence of the unique insertion of NNNGDNGREGKDEDKRDGNN was reported. The KLKQP motif was conserved in all the studied isolates. At the central repeat region, 11 haplotypes were seen with a Hapd of 0.779 ± 0.00097. The analysis of the genetic diversity in the C-terminal region showed the presence of 10 haplotypes with a Hapd of 0.457 ± 0.073. Several non-synonymous amino acids changes were also seen at the Th2R and the Th3R T-cell epitope regions including T317K, E317K, Q318E, K321N, I322K, T322K, R322K, K324Q, I327L, G352N, S354P, R355K, N356D, Q357E, and E361A. Conclusions In this study, the results indicated a high conservation at the pfcsp gene. This may further contribute in understanding the genetic polymorphisms of P. falciparum prior to the deployment of the RTS,S vaccine in Sudan.
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Affiliation(s)
- Nouh Saad Mohamed
- Department of Parasitology and Medical Entomology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan. .,Molecular Biology Unit, Sirius Training and Research Centre, Khartoum, Sudan.
| | - Hanadi AbdElbagi
- Molecular Biology Unit, Sirius Training and Research Centre, Khartoum, Sudan
| | | | | | - Yassir Osman Mohammed
- Department of Parasitology and Medical Entomology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Lubna Taj Elssir
- Department of Parasitology and Medical Entomology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Mohammed-Ahmed B Elnour
- Department of Parasitology and Medical Entomology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Yousif Ali
- Health Emergencies and Epidemics Control General Directorate, Sudan Federal Ministry of Health, Khartoum, Sudan
| | - Mohamed S Ali
- Faculty of Medicine, EL-Neelain University, Khartoum, Sudan
| | - Omnia Altahir
- Department of Parasitology and Medical Entomology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Mustafa Abubakr
- Department of the Integrated Vector Management (IVM), Federal Ministry of Health, Khartoum, Sudan
| | | | - Ayman Ahmed
- Molecular Biology Unit, Sirius Training and Research Centre, Khartoum, Sudan
| | - Rihab Ali Omer
- Pediatric Epidemiology, Clinic and Polyclinic for Child and Adolescent Medicine, Medical Faculty, University of Leipzig, Leipzig, Germany
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Chandramohan D, Zongo I, Sagara I, Cairns M, Yerbanga RS, Diarra M, Nikièma F, Tapily A, Sompougdou F, Issiaka D, Zoungrana C, Sanogo K, Haro A, Kaya M, Sienou AA, Traore S, Mahamar A, Thera I, Diarra K, Dolo A, Kuepfer I, Snell P, Milligan P, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Ouédraogo JB, Dicko A, Greenwood B. Seasonal Malaria Vaccination with or without Seasonal Malaria Chemoprevention. N Engl J Med 2021; 385:1005-1017. [PMID: 34432975 DOI: 10.1056/nejmoa2026330] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Malaria control remains a challenge in many parts of the Sahel and sub-Sahel regions of Africa. METHODS We conducted an individually randomized, controlled trial to assess whether seasonal vaccination with RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria and whether the two interventions combined were superior to either one alone in preventing uncomplicated malaria and severe malaria-related outcomes. RESULTS We randomly assigned 6861 children 5 to 17 months of age to receive sulfadoxine-pyrimethamine and amodiaquine (2287 children [chemoprevention-alone group]), RTS,S/AS01E (2288 children [vaccine-alone group]), or chemoprevention and RTS,S/AS01E (2286 children [combination group]). Of these, 1965, 1988, and 1967 children in the three groups, respectively, received the first dose of the assigned intervention and were followed for 3 years. Febrile seizure developed in 5 children the day after receipt of the vaccine, but the children recovered and had no sequelae. There were 305 events of uncomplicated clinical malaria per 1000 person-years at risk in the chemoprevention-alone group, 278 events per 1000 person-years in the vaccine-alone group, and 113 events per 1000 person-years in the combination group. The hazard ratio for the protective efficacy of RTS,S/AS01E as compared with chemoprevention was 0.92 (95% confidence interval [CI], 0.84 to 1.01), which excluded the prespecified noninferiority margin of 1.20. The protective efficacy of the combination as compared with chemoprevention alone was 62.8% (95% CI, 58.4 to 66.8) against clinical malaria, 70.5% (95% CI, 41.9 to 85.0) against hospital admission with severe malaria according to the World Health Organization definition, and 72.9% (95% CI, 2.9 to 92.4) against death from malaria. The protective efficacy of the combination as compared with the vaccine alone against these outcomes was 59.6% (95% CI, 54.7 to 64.0), 70.6% (95% CI, 42.3 to 85.0), and 75.3% (95% CI, 12.5 to 93.0), respectively. CONCLUSIONS Administration of RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria. The combination of these interventions resulted in a substantially lower incidence of uncomplicated malaria, severe malaria, and death from malaria than either intervention alone. (Funded by the Joint Global Health Trials and PATH; ClinicalTrials.gov number, NCT03143218.).
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Affiliation(s)
- Daniel Chandramohan
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Issaka Zongo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Issaka Sagara
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Matthew Cairns
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Rakiswendé-Serge Yerbanga
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Modibo Diarra
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Frédéric Nikièma
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Amadou Tapily
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Frédéric Sompougdou
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Djibrilla Issiaka
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Charles Zoungrana
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Koualy Sanogo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Alassane Haro
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Mahamadou Kaya
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Abdoul-Aziz Sienou
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Seydou Traore
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Almahamoudou Mahamar
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Ismaila Thera
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Kalifa Diarra
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Amagana Dolo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Irene Kuepfer
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Paul Snell
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Paul Milligan
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Christian Ockenhouse
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Opokua Ofori-Anyinam
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Halidou Tinto
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Abdoulaye Djimde
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Jean-Bosco Ouédraogo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Alassane Dicko
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Brian Greenwood
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
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Pirahmadi S, Zakeri S, Djadid ND, Mehrizi AA. A review of combination adjuvants for malaria vaccines: a promising approach for vaccine development. Int J Parasitol 2021; 51:699-717. [PMID: 33798560 DOI: 10.1016/j.ijpara.2021.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 12/18/2020] [Accepted: 01/28/2021] [Indexed: 01/16/2023]
Abstract
It is obvious that there is a critical need for an efficient malaria vaccine to accelerate malaria eradication. Currently, recombinant subunit vaccination against malaria using proteins and peptides is gaining attention. However, one of the major drawbacks of this approach is the lack of an efficient and durable immune response. Therefore, subunit vaccines require adjuvants to make the vaccine sufficiently immunogenic. Considering the history of the RTS,S vaccine, it seems likely that no single adjuvant is capable of eliciting all the protective immune responses required in many malarial subunit vaccines and the use of combination adjuvants will be increasingly important as the science of malaria vaccines advances. In light of this, it appears that identifying the most effective mixture of adjuvants with minimal adverse effects offers tremendous opportunities in improving the efficacy of vaccines against malaria. Owing to the importance of a multi-adjuvanted approach in subunit malaria vaccine development, this review paper outlines some of the best known combination adjuvants used in malaria subunit vaccines, focusing on their proposed mechanisms of action, their immunological properties, and their notable results. The aim of the present review is to consolidate these findings to aid the application of these combination adjuvants in experimental malaria vaccines.
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Affiliation(s)
- Sakineh Pirahmadi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran.
| | - Navid D Djadid
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Akram A Mehrizi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
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Arora N, C Anbalagan L, Pannu AK. Towards Eradication of Malaria: Is the WHO's RTS,S/AS01 Vaccination Effective Enough? Risk Manag Healthc Policy 2021; 14:1033-1039. [PMID: 33737844 PMCID: PMC7966294 DOI: 10.2147/rmhp.s219294] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/26/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Recent advances in mosquito eradication and antimalarial treatments have reduced the malaria burden only modestly. An effective malaria vaccine remains a high priority, but its development has several challenges. Among many potential candidates, the RTS,S/AS01 vaccine (MosquirixTM) remains the leading candidate. OBJECTIVE AND METHOD This review aims to understand the advances in the RTS,S/AS01 vaccine, and future comments regarding the vaccine's effectiveness in malaria eradication. Literature review for the past five decades was performed searching PubMed, EMBASE Ovid, and Cochrane Library, with using the following search items: ("malaria" OR "WHO's malaria" OR "Plasmodium falciparum" OR "RTS,S" OR "RTS,S/AS01" OR "RTS,S/AS02" OR "pre-erythrocytic malaria" OR "circumsporozoite" OR "Mosquirix") AND ("vaccine" OR "vaccination"). RESULTS RTS,S/AS01, a recombinant pre-erythrocytic vaccine containing Plasmodium falciparum surface-protein (circumsporozoite) antigen, is safe, well-tolerated, and immunogenic in children. Three doses, along with a booster, have a modest efficacy of about 36% in children (age 5-17 months) and about 26% in infants (age 6-12 weeks) against clinical malaria during a 48-month follow-up. However, the efficacy varies among population subgroups and with the parasite strain, it reduces without a booster and offers protection for a limited duration. Because of its potential cost-effectiveness and positive public health effect, the vaccine is being investigated in a pilot program for mortality benefits and broader deployment. CONCLUSION The RTS,S/AS01 vaccine prevents malaria; however, it should be considered another addition to the malaria-control program and not as an eradication tool because of its relatively low to modest efficacy.
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Affiliation(s)
- Navneet Arora
- Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | | | - Ashok K Pannu
- Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Abstract
Introduction: An effective vaccine against malaria forms a global health priority. Both naturally acquired immunity and sterile protection induced by irradiated sporozoite immunization were described decades ago. Still no vaccine exists that sufficiently protects children in endemic areas. Identifying immunological correlates of vaccine efficacy can inform rational vaccine design and potentially accelerate clinical development.Areas covered: We discuss recent research on immunological correlates of malaria vaccine efficacy, including: insights from state-of-the-art omics platforms and systems vaccinology analyses; functional anti-parasitic assays; pre-immunization predictors of vaccine efficacy; and comparison of correlates of vaccine efficacy against controlled human malaria infections (CHMI) and against naturally acquired infections.Expert Opinion: Effective vaccination may be achievable without necessarily understanding immunological correlates, but the relatively disappointing efficacy of malaria vaccine candidates in target populations is concerning. Hypothesis-generating omics and systems vaccinology analyses, alongside assessment of pre-immunization correlates, have the potential to bring about paradigm-shifts in malaria vaccinology. Functional assays may represent in vivo effector mechanisms, but have scarcely been formally assessed as correlates. Crucially, evidence is still meager that correlates of vaccine efficacy against CHMI correspond with those against naturally acquired infections in target populations. Finally, the diversity of immunological assays and efficacy endpoints across malaria vaccine trials remains a major confounder.
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Affiliation(s)
| | - Matthew B B McCall
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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Almeida MEMD, Vasconcelos MGSD, Tarragô AM, Mariúba LAM. Circumsporozoite Surface Protein-based malaria vaccines: a review. Rev Inst Med Trop Sao Paulo 2021; 63:e11. [PMID: 33533814 PMCID: PMC7845937 DOI: 10.1590/s1678-9946202163011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 10/20/2020] [Indexed: 12/03/2022] Open
Abstract
Malaria represents a serious public health problem, presenting with high rates of incidence, morbidity and mortality in tropical and subtropical regions of the world. According to the World Health Organization, in 2018 there were 228 million cases and 405 thousand deaths caused by this disease in the world, affecting mainly children and pregnant women in Africa. Despite the programs carried out to control this disease, drug resistance and invertebrate vector resistance to insecticides have generated difficulties. An efficient vaccine against malaria would be a strategy with a high impact on the eradication and control of this disease. Researches aimed at developing vaccines have focused on antigens of high importance for the survival of the parasite such as the Circumsporozoite Surface Protein, involved in the pre-erythrocytic cycle during parasites invasion in hepatocytes. Currently, RTS’S is the most promising vaccine for malaria and was constructed using CSP; its performance was evaluated using two types of adjuvants: AS01 and AS02. The purpose of this review was to provide a bibliographic survey of historical researches that led to the development of RTS’S and its performance analysis over the decade. The search for new adjuvants to be associated with this antigen seems to be a way to obtain higher percentages of protection for a future malaria vaccine.
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Affiliation(s)
- Maria Edilene Martins de Almeida
- Fiocruz Amazônia, Instituto Leônidas e Maria Deane, Laboratório de Diagnóstico e Controle de Doenças Infecciosas na Amazônia, Amazonas, Manaus, Brazil.,Fiocruz, Instituto Oswaldo Cruz, Programa de Pós-Graduação Stricto Sensu em Biologia Celular e Molecular, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria Gabriella Santos de Vasconcelos
- Fiocruz Amazônia, Instituto Leônidas e Maria Deane, Laboratório de Diagnóstico e Controle de Doenças Infecciosas na Amazônia, Amazonas, Manaus, Brazil.,Centro Universitário Fametro, Manaus, Amazonas, Brazil
| | - Andréa Monteiro Tarragô
- Universidade Federal do Amazonas, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Imunologia Básica e Aplicada, Manaus, Amazonas, Brazil.,Fundação Hospitalar de Hematologia e Hemoterapia do Amazonas, Manaus, Amazonas, Brazil
| | - Luís André Morais Mariúba
- Fiocruz Amazônia, Instituto Leônidas e Maria Deane, Laboratório de Diagnóstico e Controle de Doenças Infecciosas na Amazônia, Amazonas, Manaus, Brazil.,Fiocruz, Instituto Oswaldo Cruz, Programa de Pós-Graduação Stricto Sensu em Biologia Celular e Molecular, Rio de Janeiro, Rio de Janeiro, Brazil.,Universidade Federal do Amazonas, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Imunologia Básica e Aplicada, Manaus, Amazonas, Brazil.,Universidade Federal do Amazonas, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biotecnologia, Manaus, Amazonas, Brazil
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Amegashie EA, Amenga-Etego L, Adobor C, Ogoti P, Mbogo K, Amambua-Ngwa A, Ghansah A. Population genetic analysis of the Plasmodium falciparum circumsporozoite protein in two distinct ecological regions in Ghana. Malar J 2020; 19:437. [PMID: 33246470 PMCID: PMC7694917 DOI: 10.1186/s12936-020-03510-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/19/2020] [Indexed: 01/02/2023] Open
Abstract
Background Extensive genetic diversity in the Plasmodium falciparum circumsporozoite protein (PfCSP) is a major contributing factor to the moderate efficacy of the RTS,S/AS01 vaccine. The transmission intensity and rates of recombination within and between populations influence the extent of its genetic diversity. Understanding the extent and dynamics of PfCSP genetic diversity in different transmission settings will help to interpret the results of current RTS,S efficacy and Phase IV implementation trials conducted within and between populations in malaria-endemic areas such as Ghana. Methods Pfcsp sequences were retrieved from the Illumina-generated paired-end short-read sequences of 101 and 131 malaria samples from children aged 6–59 months presenting with clinical malaria at health facilities in Cape Coast (in the coastal belt) and Navrongo (Guinea savannah region), respectively, in Ghana. The sequences were mapped onto the 3D7 reference strain genome to yield high-quality genome-wide coding sequence data. Following data filtering and quality checks to remove missing data, 220 sequences were retained and analysed for the allele frequency spectrum, genetic diversity both within the host and between populations and signatures of selection. Population genetics tools were used to determine the extent and dynamics of Pfcsp diversity in P. falciparum from the two geographically distinct locations in Ghana. Results Pfcsp showed extensive diversity at the two sites, with the higher transmission site, Navrongo, exhibiting higher within-host and population-level diversity. The vaccine strain C-terminal epitope of Pfcsp was found in only 5.9% and 45.7% of the Navrongo and Cape Coast sequences, respectively. Between 1 and 6 amino acid variations were observed in the TH2R and TH3R epitope regions of PfCSP. Tajima’s D was negatively skewed, especially for the population from Cape Coast, given the expected historical population expansion. In contrast, a positive Tajima’s D was observed for the Navrongo P. falciparum population, consistent with balancing selection acting on the immuno-dominant TH2R and TH3R vaccine epitopes. Conclusion The low frequencies of the Pfcsp vaccine haplotype in the analysed populations indicate a need for additional molecular and immuno-epidemiological studies with broader temporal and geographic sampling in endemic populations targeted for RTS,S application. These results have implications for the efficacy of the vaccine in Ghana and will inform the choice of alleles to be included in future multivalent or chimeric vaccines.
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Affiliation(s)
- Elikplim A Amegashie
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Juja, Kenya
| | - Lucas Amenga-Etego
- Department of Biochemistry, Cell and Molecular Biology, West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, Legon, Ghana
| | - Courage Adobor
- Parasitology Department, Noguchi Memorial Institute of Medical Research, University of Ghana, , Legon, Ghana
| | - Peter Ogoti
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Juja, Kenya
| | - Kevin Mbogo
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Juja, Kenya
| | - Alfred Amambua-Ngwa
- Disease Control and Elimination, Medical Research Council Unit, The Gambia Unit, Bakau, The Gambia
| | - Anita Ghansah
- Parasitology Department, Noguchi Memorial Institute of Medical Research, University of Ghana, , Legon, Ghana.
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McCann RS, Cohee LM, Goupeyou-Youmsi J, Laufer MK. Maximizing Impact: Can Interventions to Prevent Clinical Malaria Reduce Parasite Transmission? Trends Parasitol 2020; 36:906-913. [PMID: 32917511 PMCID: PMC7581555 DOI: 10.1016/j.pt.2020.07.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/19/2020] [Accepted: 07/20/2020] [Indexed: 10/23/2022]
Abstract
Malaria interventions may reduce the burden of clinical malaria disease, the transmission of malaria parasites, or both. As malaria interventions are developed and evaluated, including those interventions primarily targeted at reducing disease, they may also impact parasite transmission. Achieving global malaria eradication will require optimizing the transmission-reducing potential of all available interventions. Herein, we discuss the relationship between malaria parasite transmission and disease, including mechanisms by which disease-targeting interventions might also impact parasite transmission. We then focus on three malaria interventions with strong evidence for reducing the burden of clinical malaria disease and examine their potential for also reducing malaria parasite transmission.
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Affiliation(s)
- Robert S McCann
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Lauren M Cohee
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jessy Goupeyou-Youmsi
- MAC Communicable Diseases Action Centre, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Miriam K Laufer
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
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31
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Thompson HA, Hogan AB, Walker PGT, White MT, Cunnington AJ, Ockenhouse CF, Ghani AC. Modelling the roles of antibody titre and avidity in protection from Plasmodium falciparum malaria infection following RTS,S/AS01 vaccination. Vaccine 2020; 38:7498-7507. [PMID: 33041104 PMCID: PMC7607256 DOI: 10.1016/j.vaccine.2020.09.069] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 08/21/2020] [Accepted: 09/24/2020] [Indexed: 12/16/2022]
Abstract
Models capturing key malaria life-cycle stages can help us evaluate vaccine candidates. Model fitting revealed antibody avidity to be an important determinant of RTS,S vaccine efficacy. High avidity and titre were associated with increased levels of vaccine efficacy. Did not identify any thresholds of protection for either immune marker.
Anti-circumsporozoite antibody titres have been established as an essential indicator for evaluating the immunogenicity and protective capacity of the RTS,S/AS01 malaria vaccine. However, a new delayed-fractional dose regime of the vaccine was recently shown to increase vaccine efficacy, from 62.5% (95% CI 29.4–80.1%) under the original dosing schedule to 86.7% (95% CI, 66.8–94.6%) without a corresponding increase in antibody titres. Here we reanalyse the antibody data from this challenge trial to determine whether IgG avidity may help to explain efficacy better than IgG titre alone by adapting a within-host mathematical model of sporozoite inoculation. We demonstrate that a model incorporating titre and avidity provides a substantially better fit to the data than titre alone. These results also suggest that in individuals with a high antibody titre response that also show high avidity (both metrics in the top tercile of observed values) delayed-fractional vaccination provided near perfect protection upon first challenge (98.2% [95% Credible Interval 91.6–99.7%]). This finding suggests that the quality of the vaccine induced antibody response is likely to be an important determinant in the development of highly efficacious pre-erythrocytic vaccines against malaria.
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Affiliation(s)
- Hayley A Thompson
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom.
| | - Alexandra B Hogan
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Patrick G T Walker
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Michael T White
- Malaria: Parasites and Hosts, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | | | | | - Azra C Ghani
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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Chandramohan D, Dicko A, Zongo I, Sagara I, Cairns M, Kuepfer I, Diarra M, Tapily A, Issiaka D, Sanogo K, Mahamar A, Sompougdou F, Yerbanga S, Thera I, Milligan P, Tinto H, Ofori-Anyinam O, Ouedraogo JB, Greenwood B. Seasonal malaria vaccination: protocol of a phase 3 trial of seasonal vaccination with the RTS,S/AS01 E vaccine, seasonal malaria chemoprevention and the combination of vaccination and chemoprevention. BMJ Open 2020; 10:e035433. [PMID: 32933955 PMCID: PMC7493088 DOI: 10.1136/bmjopen-2019-035433] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION Seasonal malaria chemoprevention (SMC), with sulphadoxine-pyrimethamine plus amodiaquine (SP+AQ) is effective but does not provide complete protection against clinical malaria. The RTS,S/AS01E malaria vaccine provides a high level of protection shortly after vaccination, but this wanes rapidly. Such a vaccine could be an alternative or additive to SMC. This trial aims to determine whether seasonal vaccination with RTS,S/AS01E vaccine could be an alternative to SMC and whether a combination of the two interventions would provide added benefits. METHODS AND ANALYSIS This is an individually randomised, double-blind, placebo-controlled trial. 5920 children aged 5-17 months were enrolled in April 2017 in Mali and Burkina Faso. Children in group 1 received three priming doses of RTS,S/AS01E vaccine before the start of the 2017 malaria transmission season and a booster dose at the beginning of two subsequent transmission seasons. In addition, they received SMC SP+AQ placebo on four occasions each year. Children in group 2 received three doses of rabies vaccine in year 1 and hepatitis A vaccine in years 2 and 3 together with four cycles of SMC SP+AQ each year. Children in group 3 received RTS,S/AS01E vaccine and four courses of SMC SP+AQ. Incidence of clinical malaria is determined by case detection at health facilities. Weekly active surveillance for malaria is undertaken in a randomly selected subset of children. The prevalence of malaria is measured in surveys at the end of each transmission season. The primary endpoint is the incidence of clinical malaria confirmed by a positive blood film with a minimum parasite density of 5000 /µL. Primary analysis will be by modified intention to treat defined as children who have received the first dose of the malaria or control vaccine. ETHICS AND DISSEMINATION The protocol was approved by the national ethics committees of Mali and Burkina Faso and the London School of Hygiene and Tropical Medicine. The results will be presented to all stakeholders and published in open access journals. TRIAL REGISTRATION NUMBER NCT03143218; Pre-results.
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Affiliation(s)
- Daniel Chandramohan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | | | - Issaka Zongo
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Matthew Cairns
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Irene Kuepfer
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | | | | | | | | | | | | | - Serge Yerbanga
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Paul Milligan
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | | | - B Greenwood
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
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Penny MA, Camponovo F, Chitnis N, Smith TA, Tanner M. Future use-cases of vaccines in malaria control and elimination. Parasite Epidemiol Control 2020; 10:e00145. [PMID: 32435704 PMCID: PMC7229487 DOI: 10.1016/j.parepi.2020.e00145] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 02/18/2020] [Accepted: 03/29/2020] [Indexed: 11/29/2022] Open
Abstract
Malaria burden has significantly changed or decreased over the last 20 years, however, it remains an important health problem requiring the rigorous application of existing tools and approaches, as well as the development and use of new interventions. A malaria vaccine has long been considered a possible new intervention to aid malaria burden reduction. However, after decades of development, only one vaccine to protect children has completed phase 3 studies. Before being widely recommended for use, it must further demonstrate safety, impact and feasibility in ongoing pilot implementation studies. Now is an appropriate time to consider the use-cases and health targets of future malaria vaccines. These must be considered in the context of likely innovations in other malaria tools such as vector control, as well as the significant knowledge gaps on the appropriate target antigens, and the immunology of vaccine-induced protection. Here we discuss the history of malaria vaccines and suggest some future use-cases for future malaria vaccines that will support achieving malaria health goals in different settings.
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Affiliation(s)
| | - Flavia Camponovo
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nakul Chitnis
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Thomas A. Smith
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Marcel Tanner
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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34
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Goswami D, Betz W, Locham NK, Parthiban C, Brager C, Schäfer C, Camargo N, Nguyen T, Kennedy SY, Murphy SC, Vaughan AM, Kappe SH. A replication-competent late liver stage-attenuated human malaria parasite. JCI Insight 2020; 5:135589. [PMID: 32484795 DOI: 10.1172/jci.insight.135589] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 05/21/2020] [Indexed: 01/06/2023] Open
Abstract
Whole-sporozoite vaccines engender sterilizing immunity against malaria in animal models and importantly, in humans. Gene editing allows for the removal of specific parasite genes, enabling generation of genetically attenuated parasite (GAP) strains for vaccination. Using rodent malaria parasites, we have previously shown that late liver stage-arresting replication-competent (LARC) GAPs confer superior protection when compared with early liver stage-arresting replication-deficient GAPs and radiation-attenuated sporozoites. However, generating a LARC GAP in the human malaria parasite Plasmodium falciparum (P. falciparum) has been challenging. Here, we report the generation and characterization of a likely unprecedented P. falciparum LARC GAP generated by targeted gene deletion of the Mei2 gene: P. falciparum mei2-. Robust exoerythrocytic schizogony with extensive cell growth and DNA replication was observed for P. falciparum mei2- liver stages in human liver-chimeric mice. However, P. falciparum mei2- liver stages failed to complete development and did not form infectious exoerythrocytic merozoites, thereby preventing their transition to asexual blood stage infection. Therefore, P. falciparum mei2- is a replication-competent, attenuated human malaria parasite strain with potentially increased potency, useful for vaccination to protect against P. falciparum malaria infection.
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Affiliation(s)
- Debashree Goswami
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - William Betz
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Navin K Locham
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | | | - Carolyn Brager
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Carola Schäfer
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Nelly Camargo
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Thao Nguyen
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Spencer Y Kennedy
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | | | - Ashley M Vaughan
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA.,Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Stefan Hi Kappe
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington, USA.,Department of Pediatrics, University of Washington, Seattle, Washington, USA
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Abstract
Malaria vaccine development entered a new era in 2015 when the pre-erythrocytic Plasmodium falciparum candidate RTS,S was favorably reviewed by the European Medicines Agency and subsequently introduced into national pilot implementation programs, marking the first human anti-parasite vaccine to pass regulatory scrutiny. Since the first trials published in 1997, RTS,S has been evaluated in a series of clinical trials culminating in Phase 3 testing, while testing of other pre-erythrocytic candidates (that target sporozoite- or liver-stage parasites), particularly whole sporozoite vaccines, has also increased. Interest in blood-stage candidates (that limit blood-stage parasite growth) subsided after disappointing human efficacy results, although new blood-stage targets and concepts may revive activity in this area. Over the past decade, testing of transmission-blocking vaccines (that kill mosquito/sexual-stage parasites) advanced to field trials and the first generation of placental malaria vaccines (that clear placenta-sequestering parasites) entered the clinic. Novel antigen discovery, human monoclonal antibodies, structural vaccinology, and improved platforms promise to expand on RTS,S and improve existing vaccine candidates.
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Affiliation(s)
- Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - J Patrick Gorres
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
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36
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Khaemba EN, Ogwang C, Kinyanjui S, Muindi JM, Koske JK, Kimani D, Ngoi J, Mwacharo J, Shangala J, Njuguna P, Mutinda D, Nyatichi E, Peshu J, Mutinda B, Ndungu FM, Farnert A, Bashraheil MM, Bejon P, Kapulu MC. Comparing drug regimens for clearance of malaria parasites in asymptomatic adults using PCR in Kilifi County, Kenya: an open-label randomised controlled clinical trial (MalPaC). Wellcome Open Res 2020. [DOI: 10.12688/wellcomeopenres.15627.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: To restrict trial endpoints to infections acquired after vaccination in Phase IIb trials of candidate malaria vaccines, participants are treated with anti-malarial drugs to clear existing infections. Anti-malarial drugs with a long half-life may inhibit the acquisition of new infections. This study evaluated the effects of three anti-malarial drug regimens on the clearance of existing infections and acquisition of new infections. Methods: An open-label randomised controlled trial (MalPaC) was conducted between November 2013 and February 2014. Ninety adults were randomised 1:1:1 to receive one of three treatments: atovaquone/proguanil and artesunate (AP+AS); artesunate (AS); or sulphadoxine-pyrimethamine, artesunate, and primaquine (SP+AS+PQ). Parasite monitoring was determined over 84-day follow-up by assessing Plasmodium falciparum positivity by 18s qPCR, live and sexual stage parasites by RT-PCR, and recrudescence of infections by msp2 genotyping. Results: At enrolment, parasite prevalence by qPCR was 44% (40/90, day 0), which fell to 10% (9/90, day 16), then rose to almost the initial rates by day 84 (39%, 35/90). Individuals treated with AS and SP+AS+PQ were more likely to have higher qPCR positive rates compared to participants treated with AP+AS in the immediate post-treatment phase (days 16-28) (OR=7.7 [95%CI 4.6-12.8] p<0.0005 and OR=4.2 [95%CI 2.6-6.8] p<0.0005, respectively). In the immediate post-treatment phase, qPCR positivity was less likely associated with evidence of live parasites and gametocytaemia. Prevalence of “old”, “new” or “undetectable” infections did not differ significantly over time or drug regimen. However, participants on the AP+AS drug regimen were less likely to have parasite infection recrudescence compared to participants treated with AS and SP+AS+PQ. Conclusion: Falciparum DNA remained detectable by PCR post-treatment with incomplete parasite clearance regardless of drug regimen. Though AP+AS drug regimen may also have partially suppressed the acquisition of new infections during post-treatment follow-up. Trial registration: Pan African Clinical Trials Registry, 22nd of August 2013, PACTR201309000625311.
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Molina-Franky J, Cuy-Chaparro L, Camargo A, Reyes C, Gómez M, Salamanca DR, Patarroyo MA, Patarroyo ME. Plasmodium falciparum pre-erythrocytic stage vaccine development. Malar J 2020; 19:56. [PMID: 32013956 PMCID: PMC6998842 DOI: 10.1186/s12936-020-3141-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 01/25/2020] [Indexed: 12/13/2022] Open
Abstract
Worldwide strategies between 2010 and 2017 aimed at controlling malarial parasites (mainly Plasmodium falciparum) led to a reduction of just 18% regarding disease incidence rates. Many biologically-derived anti-malarial vaccine candidates have been developed to date; this has involved using many experimental animals, an immense amount of work and the investment of millions of dollars. This review provides an overview of the current state and the main results of clinical trials for sporozoite-targeting vaccines (i.e. the parasite stage infecting the liver) carried out by research groups in areas having variable malaria transmission rates. However, none has led to promising results regarding the effective control of the disease, thereby making it necessary to complement such efforts at finding/introducing new vaccine candidates by adopting a multi-epitope, multi-stage approach, based on minimal subunits of the main sporozoite proteins involved in the invasion of the liver.
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Affiliation(s)
- Jessica Molina-Franky
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Laura Cuy-Chaparro
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Anny Camargo
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - César Reyes
- PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia.,Animal Science Faculty, Universidad de Ciencias Aplicadas y Ambientales (U.D.C.A), Bogotá, Colombia.,3D Structures Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Marcela Gómez
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - David Ricardo Salamanca
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Manuel Alfonso Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia. .,Basic Sciences Department, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia.
| | - Manuel Elkin Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia. .,Medical School, Universidad Nacional de Colombia, Bogotá, Colombia.
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Amelia F, Iyori M, Emran TB, Yamamoto DS, Genshi K, Otsuka H, Onoue Y, Yusuf Y, Islam A, Yoshida S. Down-selecting circumsporozoite protein-based malaria vaccine: A comparison of malaria sporozoite challenge model. Parasite Immunol 2020; 41:e12624. [PMID: 30883819 DOI: 10.1111/pim.12624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 02/28/2019] [Accepted: 03/08/2019] [Indexed: 12/18/2022]
Abstract
Plasmodium falciparum circumsporozoite protein (PfCSP) is the main target antigen in development of pre-erythrocytic malaria vaccines. To evaluate PfCSP vaccines in animal models, challenge by intravenous sporozoite injection is preferentially used. However, in clinical trials, vaccinated human volunteers are exposed to the bites of malaria-infected mosquitoes. In this study, we down-selected Escherichia coli-produced full-length PfCSP (PfCSP-F) and its three truncated PfCSPs based on their abilities to elicit immune response and protection in mice against two challenge models. We showed that immunization with three doses of PfCSP-F elicited high anti-PfCSP antibody titres and 100% protection against the bites of infected mosquitoes. Meanwhile, three-dose truncated PfCSP induced 60%-70% protection after immunization with each truncated PfCSP. Heterologous prime-boost immunization regimen with adenovirus-PfCSP-F and R32LR greatly induced complete protection against intravenous sporozoite injection. Our results suggest that Abs to both anti-repeat and anti-nonrepeat regions induced by PfCSP-F are required to confer complete protection against challenge by the bites of infected mosquitoes, whereas anti-repeat Abs play an important role in protection against intravenous sporozoite injection. Our findings provide a potential clinical application that PfCSP-F vaccine induces potent Abs capable of neutralizing sporozoites in the dermis inoculated by infected mosquitoes and subsequently sporozoites in the blood circulation.
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Affiliation(s)
- Fitri Amelia
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan.,Department of Chemistry, Universitas Negeri Padang, Padang, Indonesia
| | - Mitsuhiro Iyori
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Talha Bin Emran
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Daisuke S Yamamoto
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke, Japan
| | - Kento Genshi
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Hiromu Otsuka
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Yutaro Onoue
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Yenni Yusuf
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Ashekul Islam
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
| | - Shigeto Yoshida
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Japan
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Ho JKT, Jeevan-Raj B, Netter HJ. Hepatitis B Virus (HBV) Subviral Particles as Protective Vaccines and Vaccine Platforms. Viruses 2020; 12:v12020126. [PMID: 31973017 PMCID: PMC7077199 DOI: 10.3390/v12020126] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/13/2020] [Accepted: 01/13/2020] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B remains one of the major global health problems more than 40 years after the identification of human hepatitis B virus (HBV) as the causative agent. A critical turning point in combating this virus was the development of a preventative vaccine composed of the HBV surface (envelope) protein (HBsAg) to reduce the risk of new infections. The isolation of HBsAg sub-viral particles (SVPs) from the blood of asymptomatic HBV carriers as antigens for the first-generation vaccines, followed by the development of recombinant HBsAg SVPs produced in yeast as the antigenic components of the second-generation vaccines, represent landmark advancements in biotechnology and medicine. The ability of the HBsAg SVPs to accept and present foreign antigenic sequences provides the basis of a chimeric particulate delivery platform, and resulted in the development of a vaccine against malaria (RTS,S/AS01, MosquirixTM), and various preclinical vaccine candidates to overcome infectious diseases for which there are no effective vaccines. Biomedical modifications of the HBsAg subunits allowed the identification of strategies to enhance the HBsAg SVP immunogenicity to build potent vaccines for preventative and possibly therapeutic applications. The review provides an overview of the formation and assembly of the HBsAg SVPs and highlights the utilization of the particles in key effective vaccines.
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Affiliation(s)
- Joan Kha-Tu Ho
- Victorian Infectious Diseases Reference Laboratory (VIDRL), Melbourne Health, The Peter Doherty Institute, Melbourne, Victoria 3000, Australia; (J.K.-T.H.); (B.J.-R.)
| | - Beena Jeevan-Raj
- Victorian Infectious Diseases Reference Laboratory (VIDRL), Melbourne Health, The Peter Doherty Institute, Melbourne, Victoria 3000, Australia; (J.K.-T.H.); (B.J.-R.)
| | - Hans-Jürgen Netter
- Victorian Infectious Diseases Reference Laboratory (VIDRL), Melbourne Health, The Peter Doherty Institute, Melbourne, Victoria 3000, Australia; (J.K.-T.H.); (B.J.-R.)
- Royal Melbourne Institute of Technology (RMIT) University, School of Science, Melbourne, Victoria 3001, Australia
- Correspondence:
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40
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Yap XZ, McCall MBB, Sauerwein RW. Fast and fierce versus slow and smooth: Heterogeneity in immune responses to Plasmodium in the controlled human malaria infection model. Immunol Rev 2020; 293:253-269. [PMID: 31605396 PMCID: PMC6973142 DOI: 10.1111/imr.12811] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 09/11/2019] [Accepted: 09/13/2019] [Indexed: 12/19/2022]
Abstract
Controlled human malaria infection (CHMI) is an established model in clinical malaria research. Upon exposure to Plasmodium falciparum parasites, malaria-naive volunteers differ in dynamics and composition of their immune profiles and subsequent capacity to generate protective immunity. CHMI volunteers are either inflammatory responders who have prominent cellular IFN-γ production primarily driven by adaptive T cells, or tempered responders who skew toward antibody-mediated humoral immunity. When exposed to consecutive CHMIs under antimalarial chemoprophylaxis, individuals who can control parasitemia after a single immunization (fast responders) are more likely to be protected against a subsequent challenge infection. Fast responders tend to be inflammatory responders who can rapidly induce long-lived IFN-γ+ T cell responses. Slow responders or even non-responders can also be protected, but via a more diverse range of responses that take a longer time to reach full protective efficacy, in part due to their tempered phenotype. The latter group can be identified at baseline before CHMI by higher expression of inhibitory ligands CTLA-4 and TIM-3 on CD4+ T cells. Delineating heterogeneity in human immune responses to P. falciparum will facilitate rational design and strategy towards effective malaria vaccines.
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Affiliation(s)
- Xi Zen Yap
- Department of Medical MicrobiologyRadboud University Medical CenterNijmegenThe Netherlands
- Radboud Center for Infectious DiseasesRadboud University Medical CenterNijmegenThe Netherlands
| | - Matthew B. B. McCall
- Department of Medical MicrobiologyRadboud University Medical CenterNijmegenThe Netherlands
- Radboud Center for Infectious DiseasesRadboud University Medical CenterNijmegenThe Netherlands
| | - Robert W. Sauerwein
- Department of Medical MicrobiologyRadboud University Medical CenterNijmegenThe Netherlands
- Radboud Center for Infectious DiseasesRadboud University Medical CenterNijmegenThe Netherlands
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41
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von Seidlein L, Hanboonkunupakarn B, Jittamala P, Pongsuwan P, Chotivanich K, Tarning J, Hoglund RM, Winterberg M, Mukaka M, Peerawaranun P, Sirithiranont P, Doran Z, Ockenhouse CF, Ivinson K, Lee C, Birkett AJ, Kaslow DC, Singhasivanon P, Day NPJ, Dondorp AM, White NJ, Pukrittayakamee S. Combining antimalarial drugs and vaccine for malaria elimination campaigns: a randomized safety and immunogenicity trial of RTS,S/AS01 administered with dihydroartemisinin, piperaquine, and primaquine in healthy Thai adult volunteers. Hum Vaccin Immunother 2019; 16:33-41. [PMID: 31306084 PMCID: PMC7012096 DOI: 10.1080/21645515.2019.1643675] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Introduction: RTS,S/AS01 is currently the most advanced malaria vaccine but provides incomplete, short-term protection. It was developed for use within the expanded program on immunizations (EPI) for African children. Another use could be adding mass RTS,S/AS01 vaccination to the integrated malaria elimination strategy in the Greater Mekong Subregion (GMS), where multidrug-resistant P.falciparum strains have emerged and spread. Prior to evaluating RTS,S/AS01 in large-scale trials we assessed whether the vaccine, administered with and without antimalarial drugs, is safe and immunogenic in Asian populations. Methods: An open-label, randomized, controlled phase 2 trial was conducted in healthy, adult Thai volunteers. Seven vaccine regimens with and without antimalarial drugs (dihydroartemisinin-piperaquine plus a single low dose primaquine) were assessed. Antibody titres against the PfCSP full-length (NANP) 6, PfCSP anti-C–term, PfCSP full-length (N + C-Terminal) were measured by standard enzyme-linked immunosorbent assays. Liquid chromatography was used to measure piperaquine, primaquine and carboxy-primaquine concentrations. Results: 193 volunteers were enrolled and 186 study participants completed the 6 months follow-up period. One month after the last vaccination all study participants had seroconverted to the PfCSP (NANP)6, and the PfCSP Full Length (N + C-Terminal). More than 90% had seroconverted to the Pfanti-C-Term CSP. There was no indication that drug concentrations were influenced by vaccine regimens or the antibody levels by the drug regimens. Adverse events were similarly distributed between the seven treatment groups. No serious adverse events attributable to the study interventions were detected. Conclusion: This study found that RTS,S/AS01 with and without dihydroartemisinin-piperaquine plus a single low dose primaquine was safe and immunogenic in a healthy, adult Asian population.
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Affiliation(s)
- Lorenz von Seidlein
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Borimas Hanboonkunupakarn
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Podjanee Jittamala
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Pongphaya Pongsuwan
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kesinee Chotivanich
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Joel Tarning
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Richard M Hoglund
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Markus Winterberg
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Mavuto Mukaka
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Pimnara Peerawaranun
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Pasathorn Sirithiranont
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Zoe Doran
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | | | - Cynthia Lee
- PATH's Malaria Vaccine Initiative, Seattle, WA, USA
| | | | | | | | - Nicholas P J Day
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Arjen M Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nicholas J White
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sasithon Pukrittayakamee
- Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,The Royal Society of Thailand, Dusit, Bangkok, Thailand
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Dobaño C, Ubillos I, Jairoce C, Gyan B, Vidal M, Jiménez A, Santano R, Dosoo D, Nhabomba AJ, Ayestaran A, Aguilar R, Williams NA, Díez-Padrisa N, Lanar D, Chauhan V, Chitnis C, Dutta S, Gaur D, Angov E, Asante KP, Owusu-Agyei S, Valim C, Gamain B, Coppel RL, Cavanagh D, Beeson JG, Campo JJ, Moncunill G. RTS,S/AS01E immunization increases antibody responses to vaccine-unrelated Plasmodium falciparum antigens associated with protection against clinical malaria in African children: a case-control study. BMC Med 2019; 17:157. [PMID: 31409398 PMCID: PMC6693200 DOI: 10.1186/s12916-019-1378-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 06/27/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Vaccination and naturally acquired immunity against microbial pathogens may have complex interactions that influence disease outcomes. To date, only vaccine-specific immune responses have routinely been investigated in malaria vaccine trials conducted in endemic areas. We hypothesized that RTS,S/A01E immunization affects acquisition of antibodies to Plasmodium falciparum antigens not included in the vaccine and that such responses have an impact on overall malaria protective immunity. METHODS We evaluated IgM and IgG responses to 38 P. falciparum proteins putatively involved in naturally acquired immunity to malaria in 195 young children participating in a case-control study nested within the African phase 3 clinical trial of RTS,S/AS01E (MAL055 NCT00866619) in two sites of different transmission intensity (Kintampo high and Manhiça moderate/low). We measured antibody levels by quantitative suspension array technology and applied regression models, multimarker analysis, and machine learning techniques to analyze factors affecting their levels and correlates of protection. RESULTS RTS,S/AS01E immunization decreased antibody responses to parasite antigens considered as markers of exposure (MSP142, AMA1) and levels correlated with risk of clinical malaria over 1-year follow-up. In addition, we show for the first time that RTS,S vaccination increased IgG levels to a specific group of pre-erythrocytic and blood-stage antigens (MSP5, MSP1 block 2, RH4.2, EBA140, and SSP2/TRAP) which levels correlated with protection against clinical malaria (odds ratio [95% confidence interval] 0.53 [0.3-0.93], p = 0.03, for MSP1; 0.52 [0.26-0.98], p = 0.05, for SSP2) in multivariable logistic regression analyses. CONCLUSIONS Increased antibody responses to specific P. falciparum antigens in subjects immunized with this partially efficacious vaccine upon natural infection may contribute to overall protective immunity against malaria. Inclusion of such antigens in multivalent constructs could result in more efficacious second-generation multistage vaccines.
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Affiliation(s)
- Carlota Dobaño
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain. .,Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique.
| | - Itziar Ubillos
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - Chenjerai Jairoce
- Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - Ben Gyan
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana.,Kintampo Health Research Centre, Kintampo, Ghana
| | - Marta Vidal
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - Alfons Jiménez
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain.,Spanish Consortium for Research in Epidemiology and Public Health (CIBERESP), Madrid, Spain
| | - Rebeca Santano
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - David Dosoo
- Kintampo Health Research Centre, Kintampo, Ghana
| | - Augusto J Nhabomba
- Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - Aintzane Ayestaran
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - Ruth Aguilar
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - Nana Aba Williams
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - Núria Díez-Padrisa
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain
| | - David Lanar
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Virander Chauhan
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Chetan Chitnis
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India.,Malaria Parasite Biology and Vaccines Unit, Institut Pasteur, Paris, France
| | - Sheetij Dutta
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Deepak Gaur
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India.,Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Evelina Angov
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | | | - Seth Owusu-Agyei
- Kintampo Health Research Centre, Kintampo, Ghana.,Disease Control Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Clarissa Valim
- Department of Osteopathic Medical Specialties, Michigan State University, 909 Fee Road, Room B 309 West Fee Hall, East Lansing, MI, 48824, USA.,Department of Immunology and Infectious Diseases, Harvard T.H. Chen School of Public Health, 675 Huntington Ave., Boston, MA, 02115, USA
| | - Benoit Gamain
- Université Sorbonne Paris Cité, Université Paris Diderot, Inserm, INTS, Unité Biologie Intégrée du Globule Rouge UMR_S1134, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Ross L Coppel
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, VIC, Australia
| | - David Cavanagh
- Institute of Immunology & Infection Research and Centre for Immunity, Infection & Evolution, Ashworth Laboratories, School of Biological Sciences, University of Edinburgh, King's Buildings, Charlotte Auerbach Rd, Edinburgh, EH9 3FL, UK
| | - James G Beeson
- Macfarlane Burnet Institute for Medical Research and Public Health, Melbourne, VIC, Australia
| | - Joseph J Campo
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - Gemma Moncunill
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153, E-08036, Barcelona, Catalonia, Spain. .,Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique.
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Abstract
Despite continuous efforts, the century-old goal of eradicating malaria still remains. Multiple control interventions need to be in place simultaneously to achieve this goal. In addition to effective control measures, drug therapies and insecticides, vaccines are critical to reduce mortality and morbidity. Hence, there are numerous studies investigating various malaria vaccine candidates. Most of the malaria vaccine candidates are subunit vaccines. However, they have shown limited efficacy in Phase II and III studies. To date, only whole parasite formulations have been shown to induce sterile immunity in human. In this article, we review and discuss the recent developments in vaccination with sporozoites and the mechanisms of protection involved.
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Affiliation(s)
- Yun Shan Goh
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore
| | - Daniel McGuire
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Laurent Rénia
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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44
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Salinas ND, Tang WK, Tolia NH. Blood-Stage Malaria Parasite Antigens: Structure, Function, and Vaccine Potential. J Mol Biol 2019; 431:4259-4280. [PMID: 31103771 DOI: 10.1016/j.jmb.2019.05.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/22/2019] [Accepted: 05/08/2019] [Indexed: 10/26/2022]
Abstract
Plasmodium parasites are the causative agent of malaria, a disease that kills approximately 450,000 individuals annually, with the majority of deaths occurring in children under the age of 5 years and the development of a malaria vaccine is a global health priority. Plasmodium parasites undergo a complex life cycle requiring numerous diverse protein families. The blood stage of parasite development results in the clinical manifestation of disease. A vaccine that disrupts the blood stage is highly desired and will aid in the control of malaria. The blood stage comprises multiple steps: invasion of, asexual growth within, and egress from red blood cells. This review focuses on blood-stage antigens with emphasis on antigen structure, antigen function, neutralizing antibodies, and vaccine potential.
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Affiliation(s)
- Nichole D Salinas
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD,, 20892, USA
| | - Wai Kwan Tang
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD,, 20892, USA
| | - Niraj H Tolia
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD,, 20892, USA.
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45
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Khan S, Parrillo M, Gutierrez AH, Terry FE, Moise L, Martin WD, De Groot AS. Immune escape and immune camouflage may reduce the efficacy of RTS,S vaccine in Malawi. Hum Vaccin Immunother 2019; 16:214-227. [PMID: 30614773 PMCID: PMC7062414 DOI: 10.1080/21645515.2018.1560772] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The RTS,S/AS01 malaria vaccine will undergo a pilot vaccination study in sub-Saharan Africa beginning in 2019. RTS,S/AS01 Phase III trials reported an efficacy of 28.3% (children 5–17 months) and 18.3% (infants 6–12 weeks), with substantial variability across study sites. We postulated that the relatively low efficacy of the RTS,S vaccine and variability across sites may be due to lack of T-cell epitopes in the vaccine antigen, and due to the HLA distribution of the vaccinated population, and/or due to ‘immune camouflage’, an immune escape mechanism. To examine these hypotheses, we used immunoinformatics tools to compare T helper epitopes contained in RTS,S vaccine antigens with Plasmodium falciparum circumsporozoite protein (CSP) variants isolated from infected individuals in Malawi. The prevalence of epitopes restricted by specific HLA-DRB1 alleles was inversely associated with prevalence of the HLA-DRB1 allele in the Malawi study population, suggesting immune escape. In addition, T-cell epitopes in the CSP of strains circulating in Malawi were more often restricted by low-frequency HLA-DRB1 alleles in the population. Furthermore, T-cell epitopes that were highly conserved across CSP variants in Malawi possessed TCR-facing residues that were highly conserved in the human proteome, potentially reducing T-cell help through tolerance. The CSP component of the RTS,S vaccine also exhibited a low degree of T-cell epitope relatedness to circulating variants. These results suggest that RTS,S vaccine efficacy may be impacted by low T-cell epitope content, reduced presentation of T-cell epitopes by prevalent HLA-DRB1, high potential for human-cross-reactivity, and limited conservation with the CSP of circulating malaria strains.
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Affiliation(s)
- Sundos Khan
- Institute for Immunology and Informatics, Department of Cell and Molecular Biology, University of Rhode Island, Providence, RI, USA
| | - Matthew Parrillo
- Institute for Immunology and Informatics, Department of Cell and Molecular Biology, University of Rhode Island, Providence, RI, USA
| | | | | | - Leonard Moise
- Institute for Immunology and Informatics, Department of Cell and Molecular Biology, University of Rhode Island, Providence, RI, USA.,EpiVax, Inc., Providence, RI, USA
| | | | - Anne S De Groot
- Institute for Immunology and Informatics, Department of Cell and Molecular Biology, University of Rhode Island, Providence, RI, USA.,EpiVax, Inc., Providence, RI, USA
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Friedman-Klabanoff DJ, Laurens MB, Berry AA, Travassos MA, Adams M, Strauss KA, Shrestha B, Levine MM, Edelman R, Lyke KE. The Controlled Human Malaria Infection Experience at the University of Maryland. Am J Trop Med Hyg 2019; 100:556-565. [PMID: 30675854 PMCID: PMC6402913 DOI: 10.4269/ajtmh.18-0476] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 12/03/2018] [Indexed: 11/07/2022] Open
Abstract
Controlled human malaria infection (CHMI) is a powerful tool to evaluate the efficacy of malaria vaccines and pharmacologics. Investigators at the University of Maryland, Baltimore, Center for Vaccine Development (UMB-CVD) pioneered the technique in the 1970s and continue to advance the frontiers of CHMI research. We reviewed the records of 338 malaria-naive volunteers who underwent CHMI at UMB-CVD with Plasmodium falciparum from 1971 until 2017. These 338 volunteers underwent 387 CHMI events, including 60 via intradermal injection or direct venous inoculation (DVI) of purified, cryopreserved sporozoites. No volunteer suffered an unplanned hospitalization or required intravenous therapy related to CHMI. Median prepatency period was longer in challenges using NF54 (9 days) than in those using 7G8 (8 days), P = 0.0006 by the log-rank test. With dose optimization of DVI, the prepatent period did not differ between DVI and mosquito bite challenge (log-rank test, P = 0.66). Polymerase chain reaction (PCR) detected P. falciparum infection 3 days earlier than thick smears (P < 0.001), and diagnosis by ultrasensitive PCR was associated with less severe symptoms than smear-based diagnosis (39% versus 0%, P = 0.0003). Historical studies with NF54 showed a shorter median prepatency period of 10.3 days than more recent studies (median 11.0 days, P = 0.02) despite significantly lower salivary gland scores in earlier studies, P = 0.0001. The 47-year experience of CHMI at UMB-CVD has led to advancements in sporozoite delivery, diagnostics, and use of heterologous challenge. Additional studies on new challenge strains and genomic data to reflect regional heterogeneity will help advance the use of CHMI as supporting data for vaccine licensure.
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Affiliation(s)
- DeAnna J. Friedman-Klabanoff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Matthew B. Laurens
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Andrea A. Berry
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Mark A. Travassos
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Matthew Adams
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kathy A. Strauss
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Biraj Shrestha
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Myron M. Levine
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Robert Edelman
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kirsten E. Lyke
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
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47
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Abstract
Following successful phase 1 and 2 trials, RTS,S/AS01 was evaluated in a large phase 3 trial in 7 African countries in which 8922 young children and 6537 infants were enrolled and followed for a median of 48 and 38 months, respectively. The vaccine efficacy against uncomplicated malaria in children was 28% without booster and 36% with booster. The vaccine received the approval of the European Medical Agency in 2015, but two WHO expert committees requested more data before the programmatic use of RTS,S/AS01 in African children can be recommended. To provide such data, a very large, cluster randomized trial is currently in progress in three African countries. The integration of RTS,S/AS01 in national childhood vaccination programs will benefit the individual vaccinated child but is unlikely to make an impact on malaria transmission. Mass vaccination campaigns that include all age groups over short periods are more likely to harness the short but high protection afforded by RTS,S/AS01.
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Affiliation(s)
- Lorenz von Seidlein
- Mahidol-Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
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Wong R, Bhattacharya D. Basics of memory B-cell responses: lessons from and for the real world. Immunology 2018; 156:120-129. [PMID: 30488482 DOI: 10.1111/imm.13019] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 02/07/2023] Open
Abstract
The production of pathogen-specific B cells and antibodies underlies protective immunity elicited by most vaccines and many infections. Humoral immunity follows a regulated process by which high-affinity antibody-secreting plasma cells and memory B cells are generated. Yet for certain pathogens, protective immunity is inefficiently generated and/or maintained. For example, Dengue virus infections lead to lasting immunity against re-infection by the same serotype. However, if infected with a different Dengue serotype, the individual is predisposed to more severe disease than if he/she was completely naive. As another example, both natural infections with or vaccination against malaria do not necessarily lead to lasting immunity, as the same individual can be re-infected many times over the course of a lifetime. In this review, we discuss how these real-world problems can both instruct and be informed by recent basic studies using model organisms and antigens. An emphasis is placed on protective epitopes and functional distinctions between memory B-cell subsets in both mice and humans. Using flavivirus and Plasmodium infections as examples, we also speculate on the differences between ineffective B-cell responses that actually occur in the real world, and perfect-world responses that would generate lasting immunity.
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Affiliation(s)
- Rachel Wong
- Division of Biological and Biomedical Sciences, Washington University, St Louis, MO, USA.,Department of Immunobiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Deepta Bhattacharya
- Department of Immunobiology, University of Arizona College of Medicine, Tucson, AZ, USA
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Vallejo AF, Read RC, Arevalo-Herrera M, Herrera S, Elliott T, Polak ME. Malaria systems immunology: Plasmodium vivax induces tolerance during primary infection through dysregulation of neutrophils and dendritic cells. J Infect 2018; 77:440-447. [PMID: 30248353 PMCID: PMC6203889 DOI: 10.1016/j.jinf.2018.09.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 09/14/2018] [Accepted: 09/15/2018] [Indexed: 12/19/2022]
Abstract
OBJECTIVES To dissect the transcriptional networks underpinning immune cells responses during primary Plasmodium vivax infection of healthy human adults. METHODS We conducted network co-expression analysis of next-generation RNA sequencing data from whole blood from P. vivax and P. falciparum controlled human malaria infection (CHMI) of healthy naïve and malaria-exposed volunteers. Single cell transcription signatures were used to deconvolute the bulk RNA-Seq data into cell-specific signals. RESULTS Initial exposure to P. vivax induced activation of innate immunity, including efficient antigen presentation and complement activation. However, this effect was accompanied by strong immunosuppression mediated by dendritic cells via the induction of Indoleamine 2,3-Dioxygenase 1(IDO1) and Lymphocyte Activation Gene 3 (LAG3). Additionally, P. vivax induced depletion of neutrophil populations associated with down regulation of 3G-protein coupled receptors, CRXCR1, CXCR2 and CSF3R. Accordingly, in malaria-exposed volunteers the inflammatory response was attenuated, with a decreased class II antigen presentation in dendritic cells. While the immunosuppressive signalling was maintained between plasmodium species, response to P. falciparum was significantly more immunogenic. CONCLUSIONS In silico analyses suggest that primary infection with P. vivax induces potent immunosuppression mediated by dendritic cells, conditioning subsequent anti-malarial immune responses. Targeting immune evasion mechanisms could be an effective alternative for improving vaccine efficacy.
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Affiliation(s)
- Andres F Vallejo
- Clinical and Experimental Sciences and NIHR Southampton Biomedical Research Centre, Faculty of Medicine, University of Southampton, Southampton General Hospital, LE59, MP813, SO16 6YD, Southampton, UK
| | - Robert C Read
- Clinical and Experimental Sciences and NIHR Southampton Biomedical Research Centre, Faculty of Medicine, University of Southampton, Southampton General Hospital, LE59, MP813, SO16 6YD, Southampton, UK
| | - Myriam Arevalo-Herrera
- Caucaseco Scientific Research Center, Cali, 760043, Colombia; School of Health, Universidad del Valle, Cali, 76001, Colombia
| | | | - Tim Elliott
- Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, SO16 6YD Southampton, UK; Institute for Life Sciences, University of Southampton, SO17 1BJ, UK
| | - Marta E Polak
- Clinical and Experimental Sciences and NIHR Southampton Biomedical Research Centre, Faculty of Medicine, University of Southampton, Southampton General Hospital, LE59, MP813, SO16 6YD, Southampton, UK; Institute for Life Sciences, University of Southampton, SO17 1BJ, UK.
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Abstract
The availability of an effective and appropriately implemented malaria vaccine would form a crucial cornerstone of public health efforts to fight this disease. Despite many decades of research, however, no malaria vaccine has yet shown satisfactory protective efficacy or been rolled-out. Validated immunological substitute endpoints have the potential to accelerate clinical vaccine development by reducing the required complexity, size, duration and cost of clinical trials. Besides facilitating clinical development of existing vaccine candidates, understanding immunological mechanisms of protection may drive the development of fundamentally new vaccination approaches. In this review we focus on correlates of protection in malaria vaccine development: Does immunogenicity predict malaria vaccine efficacy and why is this question particularly difficult? Have immunological correlates accelerated malaria vaccine development in the past and will they facilitate it in the future? Does Controlled Human Malaria Infection represent a valid model for identifying such immunological correlates, or a correlate of protection against naturally-acquired malaria in itself?
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Affiliation(s)
- Matthew B B McCall
- Institut für Tropenmedizin, Universität Tübingen and Deutsches Zentrum für Infektionsforschung, Germany; Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.
| | - Peter G Kremsner
- Institut für Tropenmedizin, Universität Tübingen and Deutsches Zentrum für Infektionsforschung, Germany; Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institut für Tropenmedizin, Universität Tübingen and Deutsches Zentrum für Infektionsforschung, Germany; Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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