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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] [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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Zhou X, Zhang Q, Chen JH, Dai JF, Kassegne K. Revisiting the antigen markers of vector-borne parasitic diseases identified by immunomics: identification and application to disease control. Expert Rev Proteomics 2024; 21:205-216. [PMID: 38584506 DOI: 10.1080/14789450.2024.2336994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 03/03/2024] [Indexed: 04/09/2024]
Abstract
INTRODUCTION Protein microarray is a promising immunomic approach for identifying biomarkers. Based on our previous study that reviewed parasite antigens and recent parasitic omics research, this article expands to include information on vector-borne parasitic diseases (VBPDs), namely, malaria, schistosomiasis, leishmaniasis, babesiosis, trypanosomiasis, lymphatic filariasis, and onchocerciasis. AREAS COVERED We revisit and systematically summarize antigen markers of vector-borne parasites identified by the immunomic approach and discuss the latest advances in identifying antigens for the rational development of diagnostics and vaccines. The applications and challenges of this approach for VBPD control are also discussed. EXPERT OPINION The immunomic approach has enabled the identification and/or validation of antigen markers for vaccine development, diagnosis, disease surveillance, and treatment. However, this approach presents several challenges, including limited sample size, variability in antigen expression, false-positive results, complexity of omics data, validation and reproducibility, and heterogeneity of diseases. In addition, antigen involvement in host immune evasion and antigen sensitivity/specificity are major issues in its application. Despite these limitations, this approach remains promising for controlling VBPD. Advances in technology and data analysis methods should continue to improve candidate antigen identification, as well as the use of a multiantigen approach in diagnostic and vaccine development for VBPD control.
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Affiliation(s)
- Xia Zhou
- MOE Key Laboratory of Geriatric Diseases and Immunology, School of Biology & Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China
| | - Qianqian Zhang
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Jun-Hu Chen
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research); National Health Commission of the People's Republic of China (NHC) Key Laboratory of Parasite and Vector Biology; World Health Organization (WHO) Collaborating Center for Tropical Diseases; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China
- Hainan Tropical Diseases Research Center (Hainan Sub-Center, Chinese Center for Tropical Diseases Research), Haikou, China
| | - Jian-Feng Dai
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Kokouvi Kassegne
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- One Health Center, Shanghai Jiao Tong University, Shanghai, China
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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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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] [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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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] [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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No Roots, No Fruits: Marcel Tanner's Scholarly Contribution, Achievements in Capacity Building, and Impact in Global Health. Diseases 2022; 10:diseases10040116. [PMID: 36547202 PMCID: PMC9777716 DOI: 10.3390/diseases10040116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/11/2022] [Accepted: 11/16/2022] [Indexed: 12/05/2022] Open
Abstract
On 1 October 2022, Marcel Tanner celebrated his 70th birthday with his family and friends on the River Rhein in Basel. Trained in epidemiology (Ph.D.) and public health (MPH), Tanner devoted his entire working life to research, teaching, and capacity building. Indeed, he built up productive partnerships, fostered multinational consortia, served on numerous scientific and strategic advisory boards, and contributed measurably to improving people's health and well-being. We systematically searched the Web of Science Core Collection to identify Tanner's scholarly contribution and pursued an in-depth analysis of his scientific oeuvre including the main areas of research, pathogens, diseases, and health systems, and the geographical foci of his scholarly activities. Additionally, we examined Tanner's impact on personal and institutional capacity building in the arena of global health. We also invited a handful of colleagues to describe their experiences while working with Marcel Tanner. What transpires is a considerable breadth and depth of peer-reviewed publications in tropical medicine; epidemiology, environmental, and occupational health; parasitology; and infectious diseases. More than a third of the 622 peer-reviewed articles, the first piece published in 1978, focused on various aspects of the protozoan parasite Plasmodium and the disease it causes: malaria. Tanner trained, taught, and inspired generations of students, scientists, and practitioners all over the world. His unique ability to bring people and institutions together to work in partnership is at the heart of an impactful career in global health.
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Yu S, Wang J, Luo X, Zheng H, Wang L, Yang X, Wang Y. Transmission-Blocking Strategies Against Malaria Parasites During Their Mosquito Stages. Front Cell Infect Microbiol 2022; 12:820650. [PMID: 35252033 PMCID: PMC8889032 DOI: 10.3389/fcimb.2022.820650] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/31/2022] [Indexed: 11/24/2022] Open
Abstract
Malaria is still the most widespread parasitic disease and causes the most infections globally. Owing to improvements in sanitary conditions and various intervention measures, including the use of antimalarial drugs, the malaria epidemic in many regions of the world has improved significantly in the past 10 years. However, people living in certain underdeveloped areas are still under threat. Even in some well-controlled areas, the decline in malaria infection rates has stagnated or the rates have rebounded because of the emergence and spread of drug-resistant malaria parasites. Thus, new malaria control methods must be developed. As the spread of the Plasmodium parasite is dependent on the part of its life cycle that occurs in mosquitoes, to eliminate the possibility of malaria infections, transmission-blocking strategies against the mosquito stage should be the first choice. In fact, after the gametocyte enters the mosquito body, it undergoes a series of transformation processes over a short period, thus providing numerous potential blocking targets. Many research groups have carried out studies based on targeting the blocking of transmission during the mosquito phase and have achieved excellent results. Meanwhile, the direct killing of mosquitoes could also significantly reduce the probability of malaria infections. Microorganisms that display complex interactions with Plasmodium, such as Wolbachia and gut flora, have shown observable transmission-blocking potential. These could be used as a biological control strategy and play an important part in blocking the transmission of malaria.
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Affiliation(s)
- Shasha Yu
- Department of Tropical Medicine, College of Military Preventive Medicine, Army Medical University, Chongqing, China
| | - Jing Wang
- Department of Tropical Medicine, College of Military Preventive Medicine, Army Medical University, Chongqing, China
| | - Xue Luo
- Department of Tropical Medicine, College of Military Preventive Medicine, Army Medical University, Chongqing, China
| | - Hong Zheng
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Luhan Wang
- Department of Tropical Medicine, College of Military Preventive Medicine, Army Medical University, Chongqing, China
| | - Xuesen Yang
- Department of Tropical Medicine, College of Military Preventive Medicine, Army Medical University, Chongqing, China
| | - Ying Wang
- Department of Tropical Medicine, College of Military Preventive Medicine, Army Medical University, Chongqing, China
- *Correspondence: Ying Wang,
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Meier L, Casagrande G, Abdulla S, Masanja H. A brief history of selected malaria vaccine and medical interventions pursued by the Swiss Tropical and Public Health Institute and partners, 1943-2021. Acta Trop 2022; 225:106115. [PMID: 34464588 DOI: 10.1016/j.actatropica.2021.106115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/29/2021] [Accepted: 08/12/2021] [Indexed: 11/01/2022]
Abstract
In order to be successful in global health today, all the long-established European tropical research institutes had to undergo a transition which can be described as "hunter-gatherer" and descriptive approaches during colonial and postcolonial times to a deeper understanding of infection biology and finally to public health interventions from which populations at large can benefit. During the 1980s and 1990s, the Swiss Tropical Institute (today: Swiss Tropical and Public Health Institute, Swiss TPH) based in Basel too has changed its focus from individual medicine to a public health context. This article does not present new scientific data but takes a historical perspective. Its aim is to highlight the above-mentioned transformation by focusing on selected malaria research-cum-action interventions during the crucial period of the 1990s, which were tailored to the social-ecological settings where the disease was endemic. In order for this transformation to be successful, we intend to emphasise the importance of (i) having a fundamental understanding of local transmission; (ii) building and nurturing relationships with partner institutions; and (iii) developing a coherent research portfolio as key elements for researching and applying evidence in malaria control and elimination as part of national malaria control programmes.
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Kusi KA, Ofori EA, Akyea-Mensah K, Kyei-Baafour E, Frimpong A, Ennuson NA, Belmonte M, Ganeshan H, Huang J, Amoah LE, Villasante E, Sedegah M. Towards large-scale identification of HLA-restricted T cell epitopes from four vaccine candidate antigens in a malaria endemic community in Ghana. Vaccine 2021; 40:757-764. [PMID: 34969544 DOI: 10.1016/j.vaccine.2021.12.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 12/06/2021] [Accepted: 12/16/2021] [Indexed: 11/24/2022]
Abstract
Sterile protection against clinical malaria has been achieved in animal models and experimental human challenge studies involving immunization with radiation attenuated Plasmodium falciparum sporozoite vaccines as well as by live sporozoites under chloroquine prophylaxis. Parasite-specific IFN-γ and granzyme B-secreting CD8 + T cells have been identified as key mediators of protection. Although the exact parasite targets of protective CD8 + T cell responses are not fully defined, responses against a handful of vaccine candidate antigens have been associated with protection. Identifying the T cell targets in these antigens will facilitate the development of simpler, cost-effective, and efficacious next generation multi-epitope vaccines. The aim of this study was to identify immunodominant portions of four malaria vaccine candidate antigens using peripheral blood mononuclear cells (PBMCs) from adults with life-long exposure to malaria parasites. Cryopreserved PBMCs from 291 HLA-typed subjects were stimulated with pools of overlapping 15mer peptides spanning the entire sequences of P. falciparum circumsporozoite protein (CSP, 9 pools), apical membrane antigen 1 (AMA1, 12 pools), thrombospondin related anonymous protein (TRAP, 6 pools) and cell traversal for ookinetes and sporozoites (CelTOS, 4 pools) in FluoroSpot assays. 125 of 291 subjects made IFN-γ responses to 30 of the 31 peptide pools tested and 22 of 291 made granzyme B responses, with 20 making dual responses. The most frequent responses were to the CSP C-terminal region and the least frequent responses were to TRAP and CelTOS. There was no association between FluoroSpot responses and active malaria infection, detected by either microscopy, RDT, or PCR. In conclusion, CSP and AMA1 have relatively higher numbers of epitopes that trigger IFN-γ and granzyme B-secreting T cells in adults with life-long malaria parasite exposure compared to the other two antigens tested, and highlights the continued relevance of these two antigens as vaccine candidates.
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Affiliation(s)
- Kwadwo Asamoah Kusi
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana.
| | - Ebenezer Addo Ofori
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Kwadwo Akyea-Mensah
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Eric Kyei-Baafour
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Augustina Frimpong
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Nana Aba Ennuson
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Maria Belmonte
- Malaria Department, Naval Medical Research Center, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Harini Ganeshan
- Malaria Department, Naval Medical Research Center, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Jun Huang
- Malaria Department, Naval Medical Research Center, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Linda Eva Amoah
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | | | - Martha Sedegah
- Malaria Department, Naval Medical Research Center, MD, USA
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Mugo RM, Mwai K, Mwacharo J, Shee FM, Musyoki JN, Wambua J, Otieno E, Bejon P, Ndungu FM. Seven-year kinetics of RTS, S/AS01-induced anti-CSP antibodies in young Kenyan children. Malar J 2021; 20:452. [PMID: 34856981 PMCID: PMC8641151 DOI: 10.1186/s12936-021-03961-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 10/20/2021] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND RTS,S/AS01, the leading malaria vaccine has been recommended by the WHO for widespread immunization of children at risk. RTS,S/AS01-induced anti-CSP IgG antibodies are associated with the vaccine efficacy. Here, the long-term kinetics of RTS,S/AS01-induced antibodies was investigated. METHODS 150 participants were randomly selected from the 447 children who participated in the RTS,S/AS01 phase IIb clinical trial in 2007 from Kilifi-Kenya. Cumulatively, the retrospective follow-up period was 93 months with annual plasma samples collection. The levels of anti-CSP IgM, total IgG, IgG1, IgG2, IgG3, and IgG4 antibodies were then determined using an enzyme-linked immunosorbent assay. RESULTS RTS,S/AS01 induced high levels of anti-CSP IgG antibodies which exhibited a rapid waning over 6.5 months post-vaccination, followed by a slower decay over the subsequent years. RTS,S/AS01-induced anti-CSP IgG antibodies remained elevated above the control group levels throughout the 7 years follow-up period. The anti-CSP IgG antibodies were mostly IgG1, IgG3, IgG2, and to a lesser extent IgG4. IgG2 predominated in later timepoints. RTS,S/AS01 also induced high levels of anti-CSP IgM antibodies which increased above the control group levels by month 3. The controls exhibited increasing levels of the anti-CSP IgM antibodies which caught up with the RTS,S/AS01 vaccinees levels by month 21. In contrast, there were no measurable anti-CSP IgG antibodies among the controls. CONCLUSION RTS,S/AS01-induced anti-CSP IgG antibodies kinetics are consistent with long-lived but waning vaccine efficacy. Natural exposure induces anti-CSP IgM antibodies in children, which increases with age, but does not induce substantial levels of anti-CSP IgG antibodies.
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Affiliation(s)
- Robert M Mugo
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya.
- Institute of Immunology, Center for Infection Medicine, Freie Universtät Berlin, 14163, Berlin, Germany.
- Department of Biological Sciences, Pwani University, P.O. Box 195-80108, Kilifi, Kenya.
| | - Kennedy Mwai
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya
| | - Jedidah Mwacharo
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya
| | - Faiz M Shee
- Department of Biological Sciences, Pwani University, P.O. Box 195-80108, Kilifi, Kenya
| | - Jennifer N Musyoki
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya
| | - Juliana Wambua
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya
| | - Edward Otieno
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Francis M Ndungu
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, Kilifi, 80108, Kenya.
- Institute of Immunology, Center for Infection Medicine, Freie Universtät Berlin, 14163, Berlin, Germany.
- Department of Biological Sciences, Pwani University, P.O. Box 195-80108, Kilifi, Kenya.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Division of Infectious Diseases, Department of Medicine Solna and Centre for Molecular Medicine, Karolinska Institute, Stockholm, Sweden.
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Virnik K, Zhou W, Medvedev A, Walsh G, Perry-Anderson J, Majam V, Felber BK, Kumar S, Berkower I. Live attenuated rubella vectors expressing Plasmodium falciparum circumsporozoite protein (Pf-CSP) provide a novel malaria vaccine platform in the rhesus macaque. Biochem Biophys Res Commun 2021; 577:58-63. [PMID: 34507066 PMCID: PMC10167915 DOI: 10.1016/j.bbrc.2021.08.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 08/20/2021] [Indexed: 11/17/2022]
Abstract
There is an urgent need for a malaria vaccine that can prevent severe disease in young children and adults. Despite earlier work showing an immunological mechanism for preventing infection and reducing disease severity, there is currently no reliable vaccine that can provide durable protection. In part, this may reflect a limited number of ways that the host can respond to the NANP repeat sequences of circumsporozoite protein (CSP) in the parasite. In addition, it may reflect antigenic escape by the parasite from protective antibodies. To be successful, a vaccine must protect against repeated exposure to infected mosquitoes in endemic areas. We have created a series of live viral vectors based on the rubella vaccine strain that express multiple tandem repeats of NANP, and we demonstrate immunogenicity in a rhesus macaque model. We tested the vectors in a sequential immunization strategy. In the first step, the animals were primed with CSP-DNA vaccine and boosted with rubella/CSP vectors. In the second step, we gave rubella/CSP vectors again, followed by recombinant CSP protein. Following the second step, antibody titers were comparable to adult exposure to malaria in an endemic area. The antibodies were specific for native CSP protein on sporozoites, and they persisted for at least 1½ years in two out of three macaques. Given the safety profile of rubella vaccine in children, these vectors could be most useful in protecting young children, who are at greatest risk of severe malarial disease.
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Affiliation(s)
- Konstantin Virnik
- Lab of Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Wenshuo Zhou
- Lab of Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Alexei Medvedev
- Lab of Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Gabrielle Walsh
- Lab of Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Jasper Perry-Anderson
- Lab of Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Victoria Majam
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, CBER, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Barbara K Felber
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, 21702, USA
| | - Sanjai Kumar
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, CBER, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA
| | - Ira Berkower
- Lab of Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics, FDA, 10903 New Hampshire Ave., Silver Spring, MD, 20993, USA.
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12
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Meier L, Casagrande G, Dietler D. The Swiss Tropical and Public Health Institute: Past, present and future. Acta Trop 2021; 223:106077. [PMID: 34358511 DOI: 10.1016/j.actatropica.2021.106077] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 12/31/2022]
Abstract
Compared internationally, the history of the Swiss Tropical and Public Health Institute (Swiss TPH) is unusual. Founded in 1944, at a time of utmost isolation, it was a response to specific needs of the government of Switzerland during the Second World War. In 1943, the Swiss Federal Council approached universities in Switzerland and asked them to submit project proposal that had the potential to mitigate possible post-war unemployment and threatening economic isolation. Members of the University of Basel proposed to establish a Swiss Tropical Institute (today: Swiss TPH). With its harbour at the River Rhine, Basel was an important international transport hub. The city was and still is the headquarters of important pharmaceutical companies, such as Novartis Pharma AG and F. Hoffmann-La Roche AG, which were looking for new markets overseas. Last but not least, scientific expeditions to Africa were rather common in the 19th and the beginning of the 20th century for members of Basel's bourgeoisie. Initially, Swiss TPH focused primarily on basic research into diseases of poverty, but over the years it has developed into an important player in public, international and global health. This article sees the development of the institute as a reflection of the visions of its directors from the founder Professor Rudolf Geigy to Professor Jürg Utzinger, who is the current Swiss TPH director. It includes interviews with the four latest of them, discussing their experiences and attempts to adapt the institute to an ever changing global environment. From these lessons learnt we hope to gain insights that could be relevant for today's leaders of scientific institutes; foster public-private partnerships and contribute to solve some of the most pressing global health challenges.
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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] [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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14
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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] [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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15
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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] [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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16
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Parzych EM, Miura K, Long CA, Burns JM. Maintaining immunogenicity of blood stage and sexual stage subunit malaria vaccines when formulated in combination. PLoS One 2020; 15:e0232355. [PMID: 32348377 PMCID: PMC7190115 DOI: 10.1371/journal.pone.0232355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/13/2020] [Indexed: 11/18/2022] Open
Abstract
Background Eradication of Plasmodium falciparum malaria will likely require a multivalent vaccine, but the development of a highly efficacious subunit-based formulation has been challenging. We previously showed that production and immunogenicity of two leading vaccine targets, PfMSP119 (blood-stage) and Pfs25 (sexual stage), could be enhanced upon genetic fusion to merozoite surface protein 8 (PfMSP8). Here, we sought to optimize a Pfs25-based formulation for use in combination with rPfMSP1/8 with the goal of maintaining the immunogenicity of each subunit. Methods Comparative mouse studies were conducted to assess the effects of adjuvant selection (Alhydrogel vs. glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE)) and antigen dose (2.5 vs. 0.5 μg) on the induction of anti-Pfs25 immune responses. The antibody response (magnitude, IgG subclass profile, and transmission-reducing activity (TRA)) and cellular responses (proliferation, cytokine production) generated in response to each formulation were assessed. Similarly, immunogenicity of a bivalent vaccine containing rPfMSP1/8 and rPfs25/8 was evaluated. Results Alum-based formulations elicited strong and comparable humoral and cellular responses regardless of antigen form (unfused rPfs25 or chimeric rPfs25/8) or dose. In contrast, GLA-SE based formulations elicited differential responses as a function of both parameters, with 2.5 μg of rPfs25/8 inducing the highest titers of functional anti-Pfs25 antibodies. Based on these data, chimeric rPfs25/8 was selected and tested in a bivalent formulation with rPfMSP1/8. Strong antibody titers against Pfs25 and PfMSP119 domains were induced with GLA-SE based formulations, with no indication of antigenic competition. Conclusions We were able to generate an immunogenic bivalent vaccine designed to target multiple parasite stages that could reduce both clinical disease and parasite transmission. The use of the same PfMSP8 carrier for two different vaccine components was effective in this bivalent formulation. As such, the incorporation of additional protective targets fused to the PfMSP8 carrier into the formulation should be feasible, further broadening the protective response.
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Affiliation(s)
- Elizabeth M. Parzych
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Kazutoyo Miura
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Carole A. Long
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - James M. Burns
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Asante KP, Ansong D, Kaali S, Adjei S, Lievens M, Nana Badu L, Agyapong Darko P, Boakye Yiadom Buabeng P, Boahen O, Maria Rettig T, Agutu C, Benard Ekow Harrison S, Ntiamoah Y, Adomako Anim J, Adeniji E, Agordo Dornudo A, Gvozdenovic E, Dosoo D, Sambian D, Owusu-Boateng H, Ato Wilson E, Prempeh F, Vandoolaeghe P, Schuerman L, Owusu-Agyei S, Agbenyega T, Ofori-Anyinam O. Immunogenicity and safety of the RTS,S/AS01 malaria vaccine co-administered with measles, rubella and yellow fever vaccines in Ghanaian children: A phase IIIb, multi-center, non-inferiority, randomized, open, controlled trial. Vaccine 2020; 38:3411-3421. [PMID: 32192811 DOI: 10.1016/j.vaccine.2020.03.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/03/2020] [Accepted: 03/06/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND To optimize vaccine implementation visits for young children, it could be efficient to administer the first RTS,S/AS01 malaria vaccine dose during the Expanded Programme on Immunization (EPI) visit at 6 months of age together with Vitamin A supplementation and the third RTS,S/AS01 dose on the same day as yellow fever (YF), measles and rubella vaccines at 9 months of age. We evaluated the safety and immunogenicity of RTS,S/AS01 when co-administered with YF and combined measles-rubella (MR) vaccines. METHODS In this phase 3b, open-label, controlled study (NCT02699099), 709 Ghanaian children were randomized (1:1:1) to receive RTS,S/AS01 at 6, 7.5 and 9 months of age, and YF and MR vaccines at 9 or 10.5 months of age (RTS,S coad and RTS,S alone groups, respectively). The third group received YF and MR vaccines at 9 months of age and will receive RTS,S/AS01 at 10.5, 11.5 and 12.5 months of age (Control group). All children received Vitamin A at 6 months of age. Non-inferiority of immune responses to the vaccine antigens was evaluated 1 month following co-administration versus RTS,S/AS01 or EPI vaccines (YF and MR vaccines) alone using pre-defined non-inferiority criteria. Safety was assessed until Study month 4.5. RESULTS Non-inferiority of antibody responses to the anti-circumsporozoite and anti-hepatitis B virus surface antigens when RTS,S/AS01 was co-administered with YF and MR vaccines versus RTS,S/AS01 alone was demonstrated. Non-inferiority of antibody responses to the measles, rubella, and YF antigens when RTS,S/AS01 was co-administered with YF and MR vaccines versus YF and MR vaccines alone was demonstrated. The safety profile of all vaccines was clinically acceptable in all groups. CONCLUSIONS RTS,S/AS01 can be co-administered with Vitamin A at 6 months and with YF and MR vaccines at 9 months of age during EPI visits, without immune response impairment to any vaccine antigen or negative safety effect.
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Affiliation(s)
- Kwaku Poku Asante
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - Daniel Ansong
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Seyram Kaali
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - Samuel Adjei
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Marc Lievens
- GSK Vaccines, Avenue Fleming 20, 1300 Wavre, Belgium.
| | - Lydia Nana Badu
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | | | - Patrick Boakye Yiadom Buabeng
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Owusu Boahen
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - Theresa Maria Rettig
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Clara Agutu
- GSK Vaccines, Avenue Fleming 20, 1300 Wavre, Belgium.
| | | | - Yaw Ntiamoah
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Japhet Adomako Anim
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - Elisha Adeniji
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - Albert Agordo Dornudo
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | | | - David Dosoo
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - David Sambian
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Harry Owusu-Boateng
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | - Elvis Ato Wilson
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana.
| | - Frank Prempeh
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana
| | | | | | - Seth Owusu-Agyei
- Kintampo Health Research Center, Ghana Health Service, PO Box 200, Kintampo, Ghana; London School of Hygiene and Tropical Medicine, UK; University of Health and Allied Sciences, Ho, Ghana.
| | - Tsiri Agbenyega
- Kwame Nkrumah University of Science & Technology/Agogo Presbyterian Hospital, P.O. Box 27 Agogo, Asante Akyem, Ghana.
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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] [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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19
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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] [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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20
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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] [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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21
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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] [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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Beeson JG, Kurtovic L, Dobaño C, Opi DH, Chan JA, Feng G, Good MF, Reiling L, Boyle MJ. Challenges and strategies for developing efficacious and long-lasting malaria vaccines. Sci Transl Med 2019; 11:11/474/eaau1458. [DOI: 10.1126/scitranslmed.aau1458] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 08/05/2018] [Accepted: 11/02/2018] [Indexed: 12/24/2022]
Abstract
Although there has been major recent progress in malaria vaccine development, substantial challenges remain for achieving highly efficacious and durable vaccines against Plasmodium falciparum and Plasmodium vivax malaria. Greater knowledge of mechanisms and key targets of immunity are needed to accomplish this goal, together with new strategies for generating potent, long-lasting, functional immunity against multiple antigens. Implementation considerations in endemic areas will ultimately affect vaccine effectiveness, so innovations to simplify and enhance delivery are also needed. Whereas challenges remain, recent exciting progress and emerging knowledge promise hope for the future of malaria vaccines.
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23
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Fleck JD, Betti AH, da Silva FP, Troian EA, Olivaro C, Ferreira F, Verza SG. Saponins from Quillaja saponaria and Quillaja brasiliensis: Particular Chemical Characteristics and Biological Activities. Molecules 2019; 24:E171. [PMID: 30621160 PMCID: PMC6337100 DOI: 10.3390/molecules24010171] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 12/13/2018] [Accepted: 12/28/2018] [Indexed: 12/21/2022] Open
Abstract
Quillaja saponaria Molina represents the main source of saponins for industrial applications. Q. saponaria triterpenoids have been studied for more than four decades and their relevance is due to their biological activities, especially as a vaccine adjuvant and immunostimulant, which have led to important research in the field of vaccine development. These saponins, alone or incorporated into immunostimulating complexes (ISCOMs), are able to modulate immunity by increasing antigen uptake, stimulating cytotoxic T lymphocyte production (Th1) and cytokines (Th2) in response to different antigens. Furthermore, antiviral, antifungal, antibacterial, antiparasitic, and antitumor activities are also reported as important biological properties of Quillaja triterpenoids. Recently, other saponins from Q. brasiliensis (A. St.-Hill. & Tul.) Mart. were successfully tested and showed similar chemical and biological properties to those of Q. saponaria barks. The aim of this manuscript is to summarize the current advances in phytochemical and pharmacological knowledge of saponins from Quillaja plants, including the particular chemical characteristics of these triterpenoids. The potential applications of Quillaja saponins to stimulate further drug discovery research will be provided.
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Affiliation(s)
- Juliane Deise Fleck
- Molecular Microbiology Laboratory, Institute of Health Sciences, Feevale University, Novo Hamburgo 93525-075, RS, Brazil.
| | - Andresa Heemann Betti
- Bioanalysis Laboratory, Institute of Health Sciences, Feevale University, Novo Hamburgo 93525-075, RS, Brazil.
| | - Francini Pereira da Silva
- Molecular Microbiology Laboratory, Institute of Health Sciences, Feevale University, Novo Hamburgo 93525-075, RS, Brazil.
| | - Eduardo Artur Troian
- Molecular Microbiology Laboratory, Institute of Health Sciences, Feevale University, Novo Hamburgo 93525-075, RS, Brazil.
| | - Cristina Olivaro
- Science and Chemical Technology Department, University Center of Tacuarembó, Udelar, Tacuarembó 45000, Uruguay.
| | - Fernando Ferreira
- Organic Chemistry Department, Carbohydrates and Glycoconjugates Laboratory, Udelar, Mondevideo 11600, Uruguay.
| | - Simone Gasparin Verza
- Molecular Microbiology Laboratory, Institute of Health Sciences, Feevale University, Novo Hamburgo 93525-075, RS, Brazil.
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24
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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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25
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Ubillos I, Ayestaran A, Nhabomba AJ, Dosoo D, Vidal M, Jiménez A, Jairoce C, Sanz H, Aguilar R, Williams NA, Díez-Padrisa N, Mpina M, Sorgho H, Agnandji ST, Kariuki S, Mordmüller B, Daubenberger C, Asante KP, Owusu-Agyei S, Sacarlal J, Aide P, Aponte JJ, Dutta S, Gyan B, Campo JJ, Valim C, Moncunill G, Dobaño C. Baseline exposure, antibody subclass, and hepatitis B response differentially affect malaria protective immunity following RTS,S/AS01E vaccination in African children. BMC Med 2018; 16:197. [PMID: 30376866 PMCID: PMC6208122 DOI: 10.1186/s12916-018-1186-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 10/01/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The RTS,S/AS01E vaccine provides partial protection against malaria in African children, but immune responses have only been partially characterized and do not reliably predict protective efficacy. We aimed to evaluate comprehensively the immunogenicity of the vaccine at peak response, the factors affecting it, and the antibodies associated with protection against clinical malaria in young African children participating in the multicenter phase 3 trial for licensure. METHODS We measured total IgM, IgG, and IgG1-4 subclass antibodies to three constructs of the Plasmodium falciparum circumsporozoite protein (CSP) and hepatitis B surface antigen (HBsAg) that are part of the RTS,S vaccine, by quantitative suspension array technology. Plasma and serum samples were analyzed in 195 infants and children from two sites in Ghana (Kintampo) and Mozambique (Manhiça) with different transmission intensities using a case-control study design. We applied regression models and machine learning techniques to analyze immunogenicity, correlates of protection, and factors affecting them. RESULTS RTS,S/AS01E induced IgM and IgG, predominantly IgG1 and IgG3, but also IgG2 and IgG4, subclass responses. Age, site, previous malaria episodes, and baseline characteristics including antibodies to CSP and other antigens reflecting malaria exposure and maternal IgGs, nutritional status, and hemoglobin concentration, significantly affected vaccine immunogenicity. We identified distinct signatures of malaria protection and risk in RTS,S/AS01E but not in comparator vaccinees. IgG2 and IgG4 responses to RTS,S antigens post-vaccination, and anti-CSP and anti-P. falciparum antibody levels pre-vaccination, were associated with malaria risk over 1-year follow-up. In contrast, antibody responses to HBsAg (all isotypes, subclasses, and timepoints) and post-vaccination IgG1 and IgG3 to CSP C-terminus and NANP were associated with protection. Age and site affected the relative contribution of responses in the correlates identified. CONCLUSIONS Cytophilic IgG responses to the C-terminal and NANP repeat regions of CSP and anti-HBsAg antibodies induced by RTS,S/AS01E vaccination were associated with malaria protection. In contrast, higher malaria exposure at baseline and non-cytophilic IgG responses to CSP were associated with disease risk. Data provide new correlates of vaccine success and failure in African children and reveal key insights into the mode of action that can guide development of more efficacious next-generation vaccines.
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Affiliation(s)
- Itziar Ubillos
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Aintzane Ayestaran
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Augusto J Nhabomba
- Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - David Dosoo
- Kintampo Health Research Centre, Kintampo, Ghana
| | - Marta Vidal
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Alfons Jiménez
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain.,Spanish Consortium for Research in Epidemiology and Public Health (CIBERESP), Barcelona, Spain
| | - Chenjerai Jairoce
- Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - Hèctor Sanz
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Ruth Aguilar
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Nana Aba Williams
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Núria Díez-Padrisa
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain
| | - Maximilian Mpina
- Ifakara Health Institute, Bagamoyo Research and Training Center, P.O. Box 74, Bagamoyo, Tanzania
| | - Hermann Sorgho
- Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné (CERMEL), BP 242, Lambaréné, Gabon.,Institute of Tropical Medicine and German Center for Infection Research, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany
| | - Simon Kariuki
- Kenya Medical Research Institute (KEMRI)/Centre for Global Health Research, Kisumu, Kenya
| | - Benjamin Mordmüller
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland
| | - Claudia Daubenberger
- Ifakara Health Institute, Bagamoyo Research and Training Center, P.O. Box 74, Bagamoyo, Tanzania.,Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland
| | | | | | - Jahit Sacarlal
- Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique.,Facultade de Medicina, Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Pedro Aide
- Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - John J Aponte
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - Sheetij Dutta
- Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, USA
| | - Ben Gyan
- Kintampo Health Research Centre, Kintampo, Ghana.,Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Joseph J Campo
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - 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
| | - Gemma Moncunill
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, E-08036, Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Rua 12, Cambeve, Vila de Manhiça, CP 1929, Maputo, Mozambique
| | - Carlota Dobaño
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Carrer Rosselló 153 CEK building, 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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Safety and Immunogenicity of Seven Dosing Regimens of the Candidate RTS,S/AS01E Malaria Vaccine Integrated Within an Expanded Program on Immunization Regimen: A Phase II, Single-Center, Open, Controlled Trial in Infants in Malawi. Pediatr Infect Dis J 2018; 37:483-491. [PMID: 29432383 DOI: 10.1097/inf.0000000000001937] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND In a phase III trial, the RTS,S/AS01 malaria vaccine produced lower anti-circumsporozoite (CS) antibody titers when co-administered with Expanded Programme on Immunization vaccines (0-, 1- and 2-month schedule) at 6 to 12 weeks compared with 5 to 17 months at first vaccination. Alternative infant immunization schedules within the Expanded Programme on Immunization were investigated. METHODS This phase II, open, single-site (Blantyre, Malawi) trial was conducted in infants 1 to 7 days of age. Subjects were equally randomized across 7 groups to receive 3 doses of RTS,S/AS01E at time points that included ≤7 days, 6, 10, 14 and 26 weeks, and 9 months. All RTS,S/AS01E groups plus a control group (without RTS,S/AS01E) received Bacillus Calmette-Guérin + oral poliovirus vaccine at ≤7 days, diphtheria, tetanus, whole-cell pertussis, hepatitis B and Haemophilus influenzae type b vaccine + oral poliovirus vaccine at 6, 10, and 14 weeks and measles vaccine at 9 months; one RTS,S/AS01E group and the control additionally received hepatitis B vaccination at ≤7 days. Serum anti-CS antibody geometric mean concentration (GMC; enzyme-linked immunosorbent assay) and safety were assessed up to age 18 months. RESULTS Of the 480 infants enrolled, 391 completed the study. No causally related serious adverse event was reported. A higher frequency of fever within 7 days of RTS,S/AS01E vaccination compared with control was observed. Compared with the standard 6-, 10-, 14-week schedule, anti-CS antibody GMC ratios post-dose 3 were significantly higher in the 10-, 14- and 26-week group only (ratio 1.80; 95% confidence interval, 1.24-2.60); RTS,S/AS01E vaccination at ≤7 days and 10 and 14 weeks produced significantly lower anti-CS GMCs (ratio 0.59; 95% confidence interval, 0.38-0.92). CONCLUSIONS Initiation of RTS,S/AS01E vaccination above 6 weeks of age tended to improve anti-CS antibody responses. Neonatal vaccination was well tolerated but produced a comparatively lower immune response.
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Wang J, Zheng W, Liu F, Wang Y, He Y, Zheng L, Fan Q, Luo E, Cao Y, Cui L. Characterization of Pb51 in Plasmodium berghei as a malaria vaccine candidate targeting both asexual erythrocytic proliferation and transmission. Malar J 2017; 16:458. [PMID: 29132428 PMCID: PMC5683326 DOI: 10.1186/s12936-017-2107-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 11/02/2017] [Indexed: 11/10/2022] Open
Abstract
Background A vaccine that targets multiple developmental stages of malaria parasites would be an effective tool for malaria control and elimination. Methods A conserved gene in Plasmodium, the Plasmodium berghei gene (PBANKA_020570) encoding a 51 kDa protein (pb51 gene), was identified through search of the PlasmoDB database using a combination of expression and protein localization criteria. A partial domain of the Pb51 protein was expressed in a prokaryotic expression system (rPb51) and used for immunization in mice. The protein expression profile and localization were studied by Western blot and indirect immunofluorescence assay (IFA), respectively. The inhibitory effect of the anti-rPb51 antibodies on parasite proliferation was evaluated in erythrocytes in vivo. The transmission-blocking activity of the immune sera was determined by in vitro ookinete conversion assay and by direct mosquito feeding assay (DFA). Results The rPb51 elicited specific antibodies in mice. Western blot confirmed Pb51 expression in schizonts, gametocytes and ookinetes. IFA showed localization of Pb51 on the outer membranes of schizonts, gametocytes, zygotes, retorts, ookinetes and sporozoites of P. berghei. Mice immunized with the rPb51 protein significantly reduced parasite proliferation and gametocyte conversion in vivo. Moreover, the rPb51 antisera also significantly reduced the in vitro ookinete conversion when added into the ookinete culture medium. In DFA, mice immunized with the rPb51 reduced the prevalence of mosquito infection by 21.3% and oocyst density by 54.8%. Conclusions In P. berghei, P51 was expressed in both asexual erythrocytic and sexual stages and localized on the surface of these stages with the exception of the ring stage. The anti-rPb51 antibodies inhibited both P. berghei proliferation in mice and transmission of the parasite to mosquitoes. Electronic supplementary material The online version of this article (10.1186/s12936-017-2107-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jian Wang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China
| | - Wenqi Zheng
- Laboratory of Surgery, The Affiliated Hospital, Inner Mongolia Medical University, Hohhot, 010050, China
| | - Fei Liu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China
| | - Yaru Wang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China
| | - Yiwen He
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China
| | - Li Zheng
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China
| | - Qi Fan
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Enjie Luo
- Department of Pathogen Biology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China.
| | - Liwang Cui
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110001, Liaoning, China.,Department of Entomology, Pennsylvania State University, University Park, PA, 16802, USA
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Systems analysis of protective immune responses to RTS,S malaria vaccination in humans. Proc Natl Acad Sci U S A 2017; 114:2425-2430. [PMID: 28193898 DOI: 10.1073/pnas.1621489114] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
RTS,S is an advanced malaria vaccine candidate and confers significant protection against Plasmodium falciparum infection in humans. Little is known about the molecular mechanisms driving vaccine immunity. Here, we applied a systems biology approach to study immune responses in subjects receiving three consecutive immunizations with RTS,S (RRR), or in those receiving two immunizations of RTS,S/AS01 following a primary immunization with adenovirus 35 (Ad35) (ARR) vector expressing circumsporozoite protein. Subsequent controlled human malaria challenge (CHMI) of the vaccinees with Plasmodium-infected mosquitoes, 3 wk after the final immunization, resulted in ∼50% protection in both groups of vaccinees. Circumsporozoite protein (CSP)-specific antibody titers, prechallenge, were associated with protection in the RRR group. In contrast, ARR-induced lower antibody responses, and protection was associated with polyfunctional CD4+ T-cell responses 2 wk after priming with Ad35. Molecular signatures of B and plasma cells detected in PBMCs were highly correlated with antibody titers prechallenge and protection in the RRR cohort. In contrast, early signatures of innate immunity and dendritic cell activation were highly associated with protection in the ARR cohort. For both vaccine regimens, natural killer (NK) cell signatures negatively correlated with and predicted protection. These results suggest that protective immunity against P. falciparum can be achieved via multiple mechanisms and highlight the utility of systems approaches in defining molecular correlates of protection to vaccination.
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29
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Radin K, Clement F, Jongert E, Sterckx YGJ, Ockenhouse C, Regules J, Lemiale F, Leroux-Roels G. A monoclonal antibody-based immunoassay to measure the antibody response against the repeat region of the circumsporozoite protein of Plasmodium falciparum. Malar J 2016; 15:543. [PMID: 27825382 PMCID: PMC5101676 DOI: 10.1186/s12936-016-1596-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Accepted: 10/31/2016] [Indexed: 12/15/2022] Open
Abstract
Background The malaria vaccine candidate RTS,S/AS01 (GSK Vaccines) induces high IgG concentration against the circumsporozoite protein (CSP) of Plasmodium falciparum. In human vaccine recipients circulating anti-CSP antibody concentrations are associated with protection against infection but appear not to be the correlate of protection. However, in a humanized mouse model of malaria infection prophylactic administration of a human monoclonal antibody (MAL1C), derived from a RTS,S/AS01-immunized volunteer, directed against the CSP repeat region, conveyed full protection in a dose-dependent manner suggesting that antibodies alone are able to prevent P. falciparum infection when present in sufficiently high concentrations. A competition ELISA was developed to measure the presence of MAL1C-like antibodies in polyclonal sera from RTS,S/AS01 vaccine recipients and study their possible contribution to protection against infection. Results MAL1C-like antibodies present in polyclonal vaccine-induced sera were evaluated for their ability to compete with biotinylated monoclonal antibody MAL1C for binding sites on the capture antigen consisting of the recombinant protein encompassing 32 NANP repeats of CSP (R32LR). Serum samples were taken at different time points from participants in two RTS,S/AS01 vaccine studies (NCT01366534 and NCT01857869). Vaccine-induced protection status of the study participants was determined based on the outcome of experimental challenge with infected mosquito bites after vaccination. Optimal conditions were established to reliably detect MAL1C-like antibodies in polyclonal sera. Polyclonal anti-CSP antibodies and MAL1C-like antibody content were measured in 276 serum samples from RTS,S/AS01 vaccine recipients using the standard ELISA and MAL-1C competition ELISA, respectively. A strong correlation was observed between the results from these assays. However, no correlation was found between the results of either assay and protection against infection. Conclusions The competition ELISA to measure MAL1C-like antibodies in polyclonal sera from RTS,S/AS01 vaccine recipients was robust and reliable but did not reveal the elusive correlate of protection. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1596-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kristina Radin
- Center for Vaccinology (CEVAC), Ghent University, Ghent, Belgium
| | - Frederic Clement
- Center for Vaccinology (CEVAC), Ghent University, Ghent, Belgium
| | - Erik Jongert
- GSK Vaccines, Rue de l'Institut 89, B-1330, Rixensart, Belgium
| | - Yann G J Sterckx
- Structural Biology Research Center (SBRC), VIB, Pleinlaan 2, B-1050, Brussels, Belgium.,Research Unit for Cellular and Molecular Immunology (CMIM), VUB, Pleinlaan 2, B-1050, Brussels, Belgium
| | - Christian Ockenhouse
- PATH Malaria Vaccine Initiative (MVI), 455 Massachusetts Avenue NW, Washington, DC, 20001, USA
| | - Jason Regules
- Walter Reed Army Institute of Research (WRAIR), 503 Robert Grant Ave., Silver Spring, MD, 20910, USA
| | - Franck Lemiale
- PATH Malaria Vaccine Initiative (MVI), 455 Massachusetts Avenue NW, Washington, DC, 20001, USA
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30
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Kassegne K, Abe EM, Chen JH, Zhou XN. Immunomic approaches for antigen discovery of human parasites. Expert Rev Proteomics 2016; 13:1091-1101. [DOI: 10.1080/14789450.2016.1252675] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Kokouvi Kassegne
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| | - Eniola Michael Abe
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
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31
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Abstract
Roly Gosling and Lorenz von Seidlein consider a potential future development plan for the RTS,S/AS01 malaria vaccine.
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MESH Headings
- Cost-Benefit Analysis
- Drug Approval
- Drug Costs
- Forecasting
- Health Expenditures/trends
- Humans
- Immunization Programs/economics
- Immunization Programs/trends
- Immunization Schedule
- Infant
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/adverse effects
- Malaria Vaccines/economics
- Malaria, Falciparum/diagnosis
- Malaria, Falciparum/economics
- Malaria, Falciparum/epidemiology
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/prevention & control
- Malaria, Falciparum/transmission
- Patient Selection
- Plasmodium falciparum/immunology
- Social Change
- Time Factors
- Treatment Outcome
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/adverse effects
- Vaccines, Synthetic/economics
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Affiliation(s)
- Roly Gosling
- Global Health Group, University of California, San Francisco, San Francisco, California, United States of America
| | - Lorenz von Seidlein
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
- * E-mail:
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Neafsey DE, Juraska M, Bedford T, Benkeser D, Valim C, Griggs A, Lievens M, Abdulla S, Adjei S, Agbenyega T, Agnandji ST, Aide P, Anderson S, Ansong D, Aponte JJ, Asante KP, Bejon P, Birkett AJ, Bruls M, Connolly KM, D'Alessandro U, Dobaño C, Gesase S, Greenwood B, Grimsby J, Tinto H, Hamel MJ, Hoffman I, Kamthunzi P, Kariuki S, Kremsner PG, Leach A, Lell B, Lennon NJ, Lusingu J, Marsh K, Martinson F, Molel JT, Moss EL, Njuguna P, Ockenhouse CF, Ogutu BR, Otieno W, Otieno L, Otieno K, Owusu-Agyei S, Park DJ, Pellé K, Robbins D, Russ C, Ryan EM, Sacarlal J, Sogoloff B, Sorgho H, Tanner M, Theander T, Valea I, Volkman SK, Yu Q, Lapierre D, Birren BW, Gilbert PB, Wirth DF. Genetic Diversity and Protective Efficacy of the RTS,S/AS01 Malaria Vaccine. N Engl J Med 2015; 373:2025-2037. [PMID: 26488565 PMCID: PMC4762279 DOI: 10.1056/nejmoa1505819] [Citation(s) in RCA: 264] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND The RTS,S/AS01 vaccine targets the circumsporozoite protein of Plasmodium falciparum and has partial protective efficacy against clinical and severe malaria disease in infants and children. We investigated whether the vaccine efficacy was specific to certain parasite genotypes at the circumsporozoite protein locus. METHODS We used polymerase chain reaction-based next-generation sequencing of DNA extracted from samples from 4985 participants to survey circumsporozoite protein polymorphisms. We evaluated the effect that polymorphic positions and haplotypic regions within the circumsporozoite protein had on vaccine efficacy against first episodes of clinical malaria within 1 year after vaccination. RESULTS In the per-protocol group of 4577 RTS,S/AS01-vaccinated participants and 2335 control-vaccinated participants who were 5 to 17 months of age, the 1-year cumulative vaccine efficacy was 50.3% (95% confidence interval [CI], 34.6 to 62.3) against clinical malaria in which parasites matched the vaccine in the entire circumsporozoite protein C-terminal (139 infections), as compared with 33.4% (95% CI, 29.3 to 37.2) against mismatched malaria (1951 infections) (P=0.04 for differential vaccine efficacy). The vaccine efficacy based on the hazard ratio was 62.7% (95% CI, 51.6 to 71.3) against matched infections versus 54.2% (95% CI, 49.9 to 58.1) against mismatched infections (P=0.06). In the group of infants 6 to 12 weeks of age, there was no evidence of differential allele-specific vaccine efficacy. CONCLUSIONS These results suggest that among children 5 to 17 months of age, the RTS,S vaccine has greater activity against malaria parasites with the matched circumsporozoite protein allele than against mismatched malaria. The overall vaccine efficacy in this age category will depend on the proportion of matched alleles in the local parasite population; in this trial, less than 10% of parasites had matched alleles. (Funded by the National Institutes of Health and others.).
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33
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Agnandji ST, Fernandes JF, Bache EB, Ramharter M. Clinical development of RTS,S/AS malaria vaccine: a systematic review of clinical Phase I-III trials. Future Microbiol 2015; 10:1553-78. [PMID: 26437872 DOI: 10.2217/fmb.15.90] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The first clinical Phase III trial evaluating a malaria vaccine was completed in December 2013 at 11 sites from seven sub-Saharan African countries. This systematic review assesses data of Phase I-III trials including malaria-naive adults and adults, children and infants from malaria endemic settings in sub-Saharan Africa. The main endpoint of this systematic review was an analysis of the consistency of efficacy and immunogenicity data from respective Phase I-III trials. In addition, safety data from a pooled analysis of RTS/AS Phase II trials and RTS,S/AS01 Phase III trial were reviewed. The RTS,S/AS01 malaria vaccine may become available on the market in the coming year. If so, further strategies should address challenges on how to optimize vaccine efficacy and implementation of RTS,S/AS01 vaccine within the framework of established malaria control measures.
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Affiliation(s)
- Selidji T Agnandji
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany
| | - José F Fernandes
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany
| | - Emmanuel B Bache
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany.,Department of Medicine I, Division of Infectious Diseases & Tropical Medicine, Medical University of Vienna, Austria, Währinger Gürtel 18-20, 1190 Vienna, Austria
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34
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Romore I, Ali AM, Semali I, Mshinda H, Tanner M, Abdulla S. Assessment of parental perception of malaria vaccine in Tanzania. Malar J 2015; 14:355. [PMID: 26383545 PMCID: PMC4573291 DOI: 10.1186/s12936-015-0889-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 09/02/2015] [Indexed: 11/13/2022] Open
Abstract
Background Clinical trials of the RTS,S malaria vaccine have completed Phase III and the vaccine is on track for registration. Before making decisions about implementation, it is essential to prepare the ground for introducing the vaccine by assessing awareness and willingness to use malaria vaccines and to provide policy makers with evidence-based information on the best strategies to engage communities to manage the introduction of malaria vaccine in Tanzania. Methods In November 2011, as part of a large cross-sectional study of all 23 regions of Tanzania (mainland Tanzania and Zanzibar) was conducted during Tanzanian Integrated Measles Campaign (IMC) survey. In this study, the variables of interests were awareness and willingness to use a malaria vaccine. The main outcome measure was willingness to use a malaria vaccine. Logistic regression was used to examine the influence of predictive factors. Results A representative sample of 5502 (out of 6210) women, aged 18 years or older and with children under 11 months old, was selected to participate, using random sampling probability. Awareness of the forthcoming malaria vaccine, 11.8 % of participants in mainland Tanzania responded affirmatively, compared to 3.4 % in Zanzibar (p value <0.0001). 94.5 % of all respondents were willing to vaccinate their children against malaria, with a slight difference between mainland Tanzania (94.3 %) and Zanzibar (96.8 %) (p value = 0.0167). Conclusions Although mothers had low awareness and high willingness to use malaria vaccine, still availability of malaria vaccine RTS,S will compliment other existing malaria interventions and it will be implemented through the Immunization, Vaccines and Biologicals (IVB) programme (formerly EPI). The information generated from this study can aid policy makers in planning and setting priorities for introducing and implementing the malaria vaccine. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0889-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Idda Romore
- Swiss Tropical and Public health Institute, Socinstrasse 57, Postfach, 4002, Basel, Switzerland. .,University of Basel, Basel, Switzerland. .,Ifakara Health Institute (IHI), P.O. Box 78373, Dar Es Salaam, Tanzania.
| | - Ali Mohamed Ali
- Swiss Tropical and Public health Institute, Socinstrasse 57, Postfach, 4002, Basel, Switzerland. .,University of Basel, Basel, Switzerland. .,Ifakara Health Institute (IHI), P.O. Box 78373, Dar Es Salaam, Tanzania.
| | - Innocent Semali
- Muhimbili University of Health and Allied Science (MUHAS), P.O. Box 65015, Dar Es Salaam, Tanzania.
| | - Hassan Mshinda
- Commision for Science and Technology (COSTEC), P.O. Box 4302, Dar Es Salaam, Tanzania.
| | - Marcel Tanner
- Swiss Tropical and Public health Institute, Socinstrasse 57, Postfach, 4002, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Salim Abdulla
- Ifakara Health Institute (IHI), P.O. Box 78373, Dar Es Salaam, Tanzania.
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35
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Abstract
Although recent control measures have significantly reduced malaria cases and deaths in many endemic areas, an effective vaccine will be essential to eradicate this parasitic disease. Malaria vaccine strategies developed to date focus on different phases of the parasite's complex life cycle in the human host and mosquito vector, and include both subunit-based and whole-parasite vaccines. This review focuses on the 3 live-attenuated malaria vaccination strategies that have been tested in humans to date, and discusses their progress, challenges and the immune correlates of protection that have been identified.
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Key Words
- CPS, Chemoprophylaxis and Sporozoite immunization
- CQ, chloroquine
- CSP, circumsporozoite protein
- GAP, Genetically Attenuated Parasite
- ITV, Immunization-Treatment-Vaccination
- Malaria
- P. falciparum
- PfSPZ, P. falciparum sporozoite vaccine
- RAS, Radiation Attenuated Sporozoites
- attenuation
- i.d., intradermal
- i.v., intravenous
- pre-erythrocytic
- s.c., subcutaneous
- whole-parasite vaccines
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36
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Tanner M, Greenwood B, Whitty CJM, Ansah EK, Price RN, Dondorp AM, von Seidlein L, Baird JK, Beeson JG, Fowkes FJI, Hemingway J, Marsh K, Osier F. Malaria eradication and elimination: views on how to translate a vision into reality. BMC Med 2015; 13:167. [PMID: 26208740 PMCID: PMC4514994 DOI: 10.1186/s12916-015-0384-6] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although global efforts in the past decade have halved the number of deaths due to malaria, there are still an estimated 219 million cases of malaria a year, causing more than half a million deaths. In this forum article, we asked experts working in malaria research and control to discuss the ways in which malaria might eventually be eradicated. Their collective views highlight the challenges and opportunities, and explain how multi-factorial and integrated processes could eventually make malaria eradication a reality.
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Affiliation(s)
- Marcel Tanner
- Swiss Tropical & Public Health Institute, 4002, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Christopher J M Whitty
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Evelyn K Ansah
- Research and Development Division, Ghana Health Service, Accra, Ghana.
| | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia. .,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Arjen M Dondorp
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Lorenz von Seidlein
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - J Kevin Baird
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Eijkman-Oxford Clinical Research Unit, Jalan Diponegoro No.69, Jakarta, 10430, Indonesia.
| | - James G Beeson
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Microbiology, Monash University, 19 Innovation Walk, Victoria, 3800, Australia.
| | - Freya J I Fowkes
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia. .,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia. .,Department of Infectious Diseases, Monash University, Melbourne, Australia.
| | - Janet Hemingway
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Kevin Marsh
- African Academy of Sciences, Miotoni Road, Miotoni Lane, House No. 8 Karen, P.O. Box 24916-00502, Nairobi, Kenya.
| | - Faith Osier
- KEMRI Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.
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37
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Abstract
The development of a highly effective malaria vaccine remains a key goal to aid in the control and eventual eradication of this devastating parasitic disease. The field has made huge strides in recent years, with the first-generation vaccine RTS,S showing modest efficacy in a Phase III clinical trial. The updated 2030 Malaria Vaccine Technology Roadmap calls for a second generation vaccine to achieve 75% efficacy over two years for both Plasmodium falciparum and Plasmodium vivax, and for a vaccine that can prevent malaria transmission. Whole-parasite immunisation approaches and combinations of pre-erythrocytic subunit vaccines are now reporting high-level efficacy, whilst exciting new approaches to the development of blood-stage and transmission-blocking vaccine subunit components are entering clinical development. The development of a highly effective multi-component multi-stage subunit vaccine now appears to be a realistic ambition. This review will cover these recent developments in malaria vaccinology.
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38
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Daou M, Kouriba B, Ouédraogo N, Diarra I, Arama C, Keita Y, Sissoko S, Ouologuem B, Arama S, Bousema T, Doumbo OK, Sauerwein RW, Scholzen A. Protection of Malian children from clinical malaria is associated with recognition of multiple antigens. Malar J 2015; 14:56. [PMID: 25653026 PMCID: PMC4332451 DOI: 10.1186/s12936-015-0567-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 01/16/2015] [Indexed: 12/13/2022] Open
Abstract
Background Naturally acquired immunity to clinical malaria is thought to be mainly antibody-mediated, but reports on antigen targets are contradictory. Recognition of multiple antigens may be crucial for protection. In this study, the magnitude of antibody responses and their temporal stability was assessed for a panel of malaria antigens in relation to protection against clinical Plasmodium falciparum malaria. Methods Malian children aged two to 14 years were enrolled in a longitudinal study and followed up by passive and active case detection for seven months. Plasma was collected at enrolment and at the beginning, in the middle and after the end of the transmission season. Antibody titres to the P. falciparum-antigens apical membrane protein (AMA)-1, merozoite surface protein (MSP)-119, MSP-3, glutamine-rich protein (GLURP-R0) and circumsporozoite antigen (CSP) were assessed by enzyme-linked immunosorbent assay (ELISA) for 99 children with plasma available at all time points. Parasite carriage was determined by microscopy and nested PCR. Results Antibody titres to all antigens, except MSP-119, and the number of antigens recognized increased with age. After malaria exposure, antibody titres increased in children that had low titres at baseline, but decreased in those with high baseline responses. No significant differences were found between antibody titers for individual antigens between children remaining symptomatic or asymptomatic after exposure, after adjustment for age. Instead, children remaining asymptomatic following parasite exposure had a broader repertoire of antigen recognition. Conclusions The present study provides immune-epidemiological evidence from a limited cohort of Malian children that strong recognition of multiple antigens, rather than antibody titres for individual antigens, is associated with protection from clinical malaria. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0567-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Modibo Daou
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali. .,Department of Medical Microbiology, Radboud university medical center, Route 268, PO Box 9101, 6500, HB Nijmegen, The Netherlands.
| | - Bourèma Kouriba
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Nicolas Ouédraogo
- Centre National de Recherche et de Formation sur le Paludisme (CNRFP), Ouagadougou, Burkina Faso.
| | - Issa Diarra
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Charles Arama
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Yamoussa Keita
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Sibiri Sissoko
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Boucary Ouologuem
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Seydou Arama
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Teun Bousema
- Department of Medical Microbiology, Radboud university medical center, Route 268, PO Box 9101, 6500, HB Nijmegen, The Netherlands. .,Department of Infection and Immunity, London School of Hygiene and Tropical Medicine, London, UK.
| | - Ogobara K Doumbo
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali.
| | - Robert W Sauerwein
- Department of Medical Microbiology, Radboud university medical center, Route 268, PO Box 9101, 6500, HB Nijmegen, The Netherlands.
| | - Anja Scholzen
- Department of Medical Microbiology, Radboud university medical center, Route 268, PO Box 9101, 6500, HB Nijmegen, The Netherlands.
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Stipić F, Pletikapić G, Jakšić Ž, Frkanec L, Zgrablić G, Burić P, Lyons DM. Application of Functionalized Lanthanide-Based Nanoparticles for the Detection of Okadaic Acid-Specific Immunoglobulin G. J Phys Chem B 2015; 119:1259-64. [DOI: 10.1021/jp506382w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Filip Stipić
- Center
for Marine Research, Ruđer Bošković Institute, G. Paliaga
5, 52210 Rovinj, Croatia
| | | | - Željko Jakšić
- Center
for Marine Research, Ruđer Bošković Institute, G. Paliaga
5, 52210 Rovinj, Croatia
| | | | - Goran Zgrablić
- Time
Resolved X-ray Spectroscopy Laboratory, Elettra-Sincrotrone Trieste, 34149 Basovizza, Italy
| | - Petra Burić
- Center
for Marine Research, Ruđer Bošković Institute, G. Paliaga
5, 52210 Rovinj, Croatia
| | - Daniel M. Lyons
- Center
for Marine Research, Ruđer Bošković Institute, G. Paliaga
5, 52210 Rovinj, Croatia
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40
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Campo JJ, Aponte JJ, Skinner J, Nakajima R, Molina DM, Liang L, Sacarlal J, Alonso PL, Crompton PD, Felgner PL, Dobaño C. RTS,S vaccination is associated with serologic evidence of decreased exposure to Plasmodium falciparum liver- and blood-stage parasites. Mol Cell Proteomics 2014; 14:519-31. [PMID: 25547414 DOI: 10.1074/mcp.m114.044677] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The leading malaria vaccine candidate, RTS,S, targets the sporozoite and liver stages of the Plasmodium falciparum life cycle, yet it provides partial protection against disease associated with the subsequent blood stage of infection. Antibodies against the vaccine target, the circumsporozoite protein, have not shown sufficient correlation with risk of clinical malaria to serve as a surrogate for protection. The mechanism by which a vaccine that targets the asymptomatic sporozoite and liver stages protects against disease caused by blood-stage parasites remains unclear. We hypothesized that vaccination with RTS,S protects from blood-stage disease by reducing the number of parasites emerging from the liver, leading to prolonged exposure to subclinical levels of blood-stage parasites that go undetected and untreated, which in turn boosts pre-existing antibody-mediated blood-stage immunity. To test this hypothesis, we compared antibody responses to 824 P. falciparum antigens by protein array in Mozambican children 6 months after receiving a full course of RTS,S (n = 291) versus comparator vaccine (n = 297) in a Phase IIb trial. Moreover, we used a nested case-control design to compare antibody responses of children who did or did not experience febrile malaria. Unexpectedly, we found that the breadth and magnitude of the antibody response to both liver and asexual blood-stage antigens was significantly lower in RTS,S vaccinees, with the exception of only four antigens, including the RTS,S circumsporozoite antigen. Contrary to our initial hypothesis, these findings suggest that RTS,S confers protection against clinical malaria by blocking sporozoite invasion of hepatocytes, thereby reducing exposure to the blood-stage parasites that cause disease. We also found that antibody profiles 6 months after vaccination did not distinguish protected and susceptible children during the subsequent 12-month follow-up period but were strongly associated with exposure. Together, these data provide insight into the mechanism by which RTS,S protects from malaria.
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Affiliation(s)
- Joe J Campo
- ‡ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; §Manhiça Health Research Centre, Manhiça, Mozambique;
| | - John J Aponte
- ‡ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; §Manhiça Health Research Centre, Manhiça, Mozambique
| | - Jeff Skinner
- ¶Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD
| | - Rie Nakajima
- ‡‡Department of Medicine, University of California Irvine, Irvine, CA
| | | | - Li Liang
- ‡‡Department of Medicine, University of California Irvine, Irvine, CA
| | - Jahit Sacarlal
- §Manhiça Health Research Centre, Manhiça, Mozambique; **Faculty of Medicine, Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Pedro L Alonso
- ‡ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; §Manhiça Health Research Centre, Manhiça, Mozambique
| | - Peter D Crompton
- ¶Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD
| | - Philip L Felgner
- ‡‡Department of Medicine, University of California Irvine, Irvine, CA; ‖Antigen Discovery Inc., Irvine, CA
| | - Carlota Dobaño
- ‡ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; §Manhiça Health Research Centre, Manhiça, Mozambique
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White MT, Bejon P, Olotu A, Griffin JT, Bojang K, Lusingu J, Salim N, Abdulla S, Otsyula N, Agnandji ST, Lell B, Asante KP, Owusu-Agyei S, Mahama E, Agbenyega T, Ansong D, Sacarlal J, Aponte JJ, Ghani AC. A combined analysis of immunogenicity, antibody kinetics and vaccine efficacy from phase 2 trials of the RTS,S malaria vaccine. BMC Med 2014; 12:117. [PMID: 25012228 PMCID: PMC4227280 DOI: 10.1186/s12916-014-0117-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/19/2014] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND The RTS,S malaria vaccine is currently undergoing phase 3 trials. High vaccine-induced antibody titres to the circumsporozoite protein (CSP) antigen have been associated with protection from infection and episodes of clinical malaria. METHODS Using data from 5,144 participants in nine phase 2 trials, we explore predictors of vaccine immunogenicity (anti-CSP antibody titres), decay in antibody titres, and the association between antibody titres and clinical outcomes. We use empirically-observed relationships between these factors to predict vaccine efficacy in a range of scenarios. RESULTS Vaccine-induced anti-CSP antibody titres were significantly associated with age (P = 0.04), adjuvant (P <0.001), pre-vaccination anti-hepatitis B surface antigen titres (P = 0.005) and pre-vaccination anti-CSP titres (P <0.001). Co-administration with other vaccines reduced anti-CSP antibody titres although not significantly (P = 0.095). Antibody titres showed a bi-phasic decay over time with an initial rapid decay in the first three months and a second slower decay over the next three to four years. Antibody titres were significantly associated with protection, with a titre of 51 (95% Credible Interval (CrI): 29 to 85) ELISA units/ml (EU/mL) predicted to prevent 50% of infections in children. Vaccine efficacy was predicted to decline to zero over four years in a setting with entomological inoculation rate (EIR) = 20 infectious bites per year (ibpy). Over a five-year follow-up period at an EIR = 20 ibpy, we predict RTS,S will avert 1,782 cases per 1,000 vaccinated children, 1,452 cases per 1,000 vaccinated infants, and 887 cases per 1,000 infants when co-administered with expanded programme on immunisation (EPI) vaccines. Our main study limitations include an absence of vaccine-induced cellular immune responses and short duration of follow-up in some individuals. CONCLUSIONS Vaccine-induced anti-CSP antibody titres and transmission intensity can explain variations in observed vaccine efficacy.
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Efficacy and safety of the RTS,S/AS01 malaria vaccine during 18 months after vaccination: a phase 3 randomized, controlled trial in children and young infants at 11 African sites. PLoS Med 2014; 11:e1001685. [PMID: 25072396 PMCID: PMC4114488 DOI: 10.1371/journal.pmed.1001685] [Citation(s) in RCA: 302] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 06/18/2014] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND A malaria vaccine could be an important addition to current control strategies. We report the safety and vaccine efficacy (VE) of the RTS,S/AS01 vaccine during 18 mo following vaccination at 11 African sites with varying malaria transmission. METHODS AND FINDINGS 6,537 infants aged 6-12 wk and 8,923 children aged 5-17 mo were randomized to receive three doses of RTS,S/AS01 or comparator vaccine. VE against clinical malaria in children during the 18 mo after vaccine dose 3 (per protocol) was 46% (95% CI 42% to 50%) (range 40% to 77%; VE, p<0.01 across all sites). VE during the 20 mo after vaccine dose 1 (intention to treat [ITT]) was 45% (95% CI 41% to 49%). VE against severe malaria, malaria hospitalization, and all-cause hospitalization was 34% (95% CI 15% to 48%), 41% (95% CI 30% to 50%), and 19% (95% CI 11% to 27%), respectively (ITT). VE against clinical malaria in infants was 27% (95% CI 20% to 32%, per protocol; 27% [95% CI 21% to 33%], ITT), with no significant protection against severe malaria, malaria hospitalization, or all-cause hospitalization. Post-vaccination anti-circumsporozoite antibody geometric mean titer varied from 348 to 787 EU/ml across sites in children and from 117 to 335 EU/ml in infants (per protocol). VE waned over time in both age categories (Schoenfeld residuals p<0.001). The number of clinical and severe malaria cases averted per 1,000 children vaccinated ranged across sites from 37 to 2,365 and from -1 to 49, respectively; corresponding ranges among infants were -10 to 1,402 and -13 to 37, respectively (ITT). Meningitis was reported as a serious adverse event in 16/5,949 and 1/2,974 children and in 9/4,358 and 3/2,179 infants in the RTS,S/AS01 and control groups, respectively. CONCLUSIONS RTS,S/AS01 prevented many cases of clinical and severe malaria over the 18 mo after vaccine dose 3, with the highest impact in areas with the greatest malaria incidence. VE was higher in children than in infants, but even at modest levels of VE, the number of malaria cases averted was substantial. RTS,S/AS01 could be an important addition to current malaria control in Africa. TRIAL REGISTRATION www.ClinicalTrials.gov NCT00866619 Please see later in the article for the Editors' Summary.
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Kester KE, Gray Heppner D, Moris P, Ofori-Anyinam O, Krzych U, Tornieporth N, McKinney D, Delchambre M, Ockenhouse CF, Voss G, Holland C, Beckey JP, Ballou WR, Cohen J. Sequential Phase 1 and Phase 2 randomized, controlled trials of the safety, immunogenicity and efficacy of combined pre-erythrocytic vaccine antigens RTS,S and TRAP formulated with AS02 Adjuvant System in healthy, malaria naïve adults. Vaccine 2014; 32:6683-91. [PMID: 24950358 DOI: 10.1016/j.vaccine.2014.06.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 05/26/2014] [Accepted: 06/06/2014] [Indexed: 10/25/2022]
Abstract
In an attempt to improve the efficacy of the candidate malaria vaccine RTS,S/AS02, two studies were conducted in 1999 in healthy volunteers of RTS,S/AS02 in combination with recombinant Plasmodium falciparum thrombospondin-related anonymous protein (TRAP). In a Phase 1 safety and immunogenicity study, volunteers were randomized to receive TRAP/AS02 (N=10), RTS,S/AS02 (N=10), or RTS,S+TRAP/AS02 (N=20) at 0, 1 and 6-months. In a Phase 2 challenge study, subjects were randomized to receive either RTS,S+TRAP/AS02 (N=25) or TRAP/AS02 (N=10) at 0 and 1-month, or to a challenge control group (N=8). In both studies, the combination vaccine had an acceptable safety profile and was acceptably tolerated. Antigen-specific antibodies, lymphoproliferative responses, and IFN-γ production by ELISPOT assay elicited with the combination vaccine were qualitatively similar to those generated by the single component vaccines. However, post-dose 2 anti-CS antibodies in the RTS,S+TRAP/AS02 vaccine recipients were lower than in the RTS,S/AS02 vaccine recipients. After challenge, 10 of 11 RTS,S+TRAP/AS02 vaccinees, 5 of 5 TRAP/AS02 vaccinees, and 8 of 8 infectivity controls developed parasitemia, with median pre-patent periods of 13.0, 11.0, and 12.0 days, respectively. The absence of any prevention or delay of parasitemia by TRAP/AS02 suggests no apparent added value of TRAP/AS02 as a candidate vaccine. The absence of significant protection or delay of parasitemia in the 11 RTS,S+TRAP/AS02 vaccine recipients contrasts with previous 2 dose studies of RTS,S/AS02. The small sample size did not permit identifying statistically significant differences between the study arms. However, we speculate, within the constraints of the challenge study, that the presence of the TRAP antigen may have interfered with the vaccine efficacy previously observed with this regimen of RTS,S/AS02, and that any future TRAP-based vaccines should consider employing alternative vaccine platforms.
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Affiliation(s)
- Kent E Kester
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - D Gray Heppner
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | | | - Urszula Krzych
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | - Denise McKinney
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | | | - Gerald Voss
- GlaxoSmithKline Biologicals, Rixensart, Belgium.
| | - Carolyn Holland
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | | | - W Ripley Ballou
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - Joe Cohen
- GlaxoSmithKline Biologicals, Rixensart, Belgium.
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44
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Shepherd SM, Shoff WH. Vaccination for the expatriate and long-term traveler. Expert Rev Vaccines 2014; 13:775-800. [DOI: 10.1586/14760584.2014.913485] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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45
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Krzych U, Zarling S, Pichugin A. Memory T cells maintain protracted protection against malaria. Immunol Lett 2014; 161:189-95. [PMID: 24709142 DOI: 10.1016/j.imlet.2014.03.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 03/25/2014] [Accepted: 03/27/2014] [Indexed: 10/25/2022]
Abstract
Immunologic memory is one of the cardinal features of antigen-specific immune responses, and the persistence of memory cells contributes to prophylactic immunizations against infectious agents. Adequately maintained memory T and B cell pools assure a fast, effective and specific response against re-infections. However, many aspects of immunologic memory are still poorly understood, particularly immunologic memory inducible by parasites, for example, Plasmodium spp., the causative agents of malaria. For example, memory responses to Plasmodium antigens amongst residents of malaria endemic areas appear to be either inadequately developed or maintained, because persons who survive episodes of childhood malaria remain vulnerable to intermittent malaria infections. By contrast, multiple exposures of humans and laboratory rodents to radiation-attenuated Plasmodium sporozoites (γ-spz) induce sterile and long-lasting protection against experimental sporozoite challenge. Multifactorial immune mechanisms maintain this protracted and sterile protection. While the presence of memory CD4 T cell subsets has been associated with lasting protection in humans exposed to multiple bites from Anopheles mosquitoes infected with attenuated Plasmodium falciparum, memory CD8 T cells maintain protection induced with Plasmodium yoelii and Plasmodium berghei γ-spz in murine models. In this review, we discuss our observations that show memory CD8 T cells specific for antigens expressed by P. berghei liver stage parasites as an indispensable component for the maintenance of protracted protective immunity against experimental malaria infection; moreover, the provision of an Ag-depot assures a quick recall of memory T cells as IFN-γ-producing effector CD8 T cells and IL-4- producing CD4 T cells that collaborate with B cells for an effective antibody response.
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Affiliation(s)
- Urszula Krzych
- Department of Cellular Immunology, Branch of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States.
| | - Stasya Zarling
- Department of Cellular Immunology, Branch of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | - Alexander Pichugin
- Department of Cellular Immunology, Branch of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
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Duration of vaccine efficacy against malaria: 5th year of follow-up in children vaccinated with RTS,S/AS02 in Mozambique. Vaccine 2014; 32:2209-16. [PMID: 24631081 DOI: 10.1016/j.vaccine.2014.02.042] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 12/18/2013] [Accepted: 02/12/2014] [Indexed: 02/07/2023]
Abstract
A primary concern for the RTS,S malaria vaccine candidate is duration of protection. The ongoing Phase III trial reported evidence of waning efficacy within the first year following vaccination. Multiple Phase IIb trials demonstrated early waning of efficacy. The longest duration of protection for RTS,S recorded to date was in a trial of a cohort of 1605 Mozambican children age 1-4 yr at the time of immunization (C1), which showed an overall efficacy against clinical malaria of 30.5% over 43 subsequent months of surveillance. A significant reduction in parasite prevalence in RTS,S vaccinees indicated that the vaccine continued to protect at the end of this period. Although follow-up for recording incident cases of clinical malaria was stopped at 45 months, we were interested in evidence of further durability of protection, and revisited the cohort at 63 months, recording the secondary trial endpoint, prevalence of asexual Plasmodium falciparum parasitemia, in the RTS,S and comparator vaccine groups as a proxy for efficacy. As a comparator, we also visited the contemporaneous cohort of 417 children (C2), which showed waning efficacy after 6 months of follow-up. We also assessed anti-circumsporozoite antibody titers. These results were compared with those of other Phase IIb trials. Prevalence of parasitemia was not significantly lower in the RTS,S/AS02 group compared to comparator groups in C1 (57 [119%] Vs 62 [128%]; p=0.696) or C2 (30 [226%] Vs 35 [276%]; p=0.391), despite elevated antibody titers, suggesting that protection did not extend to 5 years after vaccination. This is in contrast to the earlier assessment of parasitemia in C1, where a 34% lower prevalence of parasitemia was observed in the RTS,S/AS02 group at month 45. Comparison with other Phase II trials highlights a complex relationship between efficacy, age and transmission intensity. RTS,S/AS02 provided partial protection from clinical malaria for at least 3.5 years in C1. Duration of protection may depend on environmental circumstances, such as changing malaria transmission, and special attention should be given in the Phase III trial to identifying factors that modify longevity of protection.
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Foquet L, Hermsen CC, van Gemert GJ, Van Braeckel E, Weening KE, Sauerwein R, Meuleman P, Leroux-Roels G. Vaccine-induced monoclonal antibodies targeting circumsporozoite protein prevent Plasmodium falciparum infection. J Clin Invest 2014; 124:140-4. [PMID: 24292709 DOI: 10.1172/jci70349] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 09/26/2013] [Indexed: 11/17/2022] Open
Abstract
Malaria, which is the result of Plasmodium falciparum infection, is a global health threat that resulted in 655,000 deaths and 216 million clinical cases in 2010 alone. Recent phase 3 trials with malaria vaccine candidate RTS,S/AS01 (RTS,S) in children has demonstrated modest efficacy against clinical and severe malaria. RTS,S targets the pre-erythrocytic phase of the disease and induces high antibody titers against the P. falciparum circumsporozoite protein (CSP) and a moderate CD4(+) T cell response. The individual contribution of these adaptive immune responses to protection from infection remains unknown. Here, we found that prophylactic administration of anti-CSP mAbs derived from an RTS,S-vaccinated recipient fully protected mice with humanized livers from i.v.- and mosquito bite–delivered P. falciparum sporozoite challenge. Titers of anti-CSP that conveyed full protection were within the range observed in human RTS,S vaccine recipients. Increasing anti-CSP titers resulted in a dose-dependent reduction of the liver parasite burden. These data indicate that RTS,S-induced antibodies are protective and provide sterilizing immunity against P. falciparum infection when reaching or exceeding a critical plasma concentration.
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48
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Regules JA, Cummings JF, Ockenhouse CF. The RTS,S vaccine candidate for malaria. Expert Rev Vaccines 2014; 10:589-99. [DOI: 10.1586/erv.11.57] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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49
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Cunnington AJ, Riley EM. Suppression of vaccine responses by malaria: insignificant or overlooked? Expert Rev Vaccines 2014; 9:409-29. [DOI: 10.1586/erv.10.16] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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50
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Mandal S. Epidemiological aspects of vivax and falciparum malaria: global spectrum. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2014. [DOI: 10.1016/s2222-1808(14)60410-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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