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Tiono AB, Palacpac NMQ, Bougouma EC, Nebie I, Ouédraogo A, Houard S, Arisue N, D’Alessio F, Horii T, Sirima SB. Plasmodium falciparum infection coinciding with the malaria vaccine candidate BK-SE36 administration interferes with the immune responses in Burkinabe children. Front Immunol 2023; 14:1119820. [PMID: 36993981 PMCID: PMC10040972 DOI: 10.3389/fimmu.2023.1119820] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/21/2023] [Indexed: 03/14/2023] Open
Abstract
BackgroundA vaccine targeting the erythrocyte stages of Plasmodium falciparum could play a role in preventing clinical disease. BK-SE36 is a promising malaria vaccine candidate that has shown a good safety profile and immunological responses during field evaluations. It was observed that repeated natural infections could result in immune tolerance against SE36 molecule.MethodsThe primary trial was conducted to assess the safety and immunogenicity of the BK-SE36 in two cohorts of children aged 25-60 months (Cohort 1) and 12-24 months (Cohort 2). Immunization was at full dose (1.0 mL) administered at 0, 1, and 6 months. Blood samples were collected before each vaccination for immunological assessments and detection of Plasmodium falciparum infection by microscopy. Blood samples were further collected one month post each vaccination to evaluate immunogenicity.ResultsOf seventy-two (72) subjects that have received BK-SE36 vaccination, 71 had available blood smears during vaccination days. One month post Dose 2, the geometric mean of SE36 antibodies was 263.2 (95% CI: 178.9-387.1) in uninfected individuals compared to 77.1 (95% CI: 47.3-125.7) in infected participants. The same trend was observed one-month post booster dose. Participants uninfected at the time of booster vaccination had significantly higher GMTs compared to those who were infected (424.1 (95% CI: 301.9-595.8) vs. 92.8 (95% CI: 34.9-246.6), p = 0.002. There was a 14.3 (95% CI: 9.7-21.1) and 2.4 (95% CI: 1.3-4.4) fold-change, respectively, in uninfected and infected participants between one-month post Dose 2 and booster. The difference was statistically significant (p < 0.001).ConclusionConcomitant infection by P. falciparum during BK-SE36 vaccine candidate administration is associated with reduced humoral responses. However, it is to be noted that the BK-SE36 primary trial was not designed to investigate the influence of concomitant infection on vaccine-induced immune response and should be interpreted cautiously.Trial registrationWHO ICTRP, PACTR201411000934120.
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Affiliation(s)
- Alfred B. Tiono
- Groupe de Recherche Action en Santé, Ouagadougou (GRAS), Ouagadougou, Burkina Faso
- Centre National de Recherche et de Formation sur le Paludisme (CNRFP), Ouagadougou, Burkina Faso
| | - Nirianne Marie Q. Palacpac
- Department of Malaria Vaccine Development, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | | | - Issa Nebie
- Groupe de Recherche Action en Santé, Ouagadougou (GRAS), Ouagadougou, Burkina Faso
| | - Alphonse Ouédraogo
- Groupe de Recherche Action en Santé, Ouagadougou (GRAS), Ouagadougou, Burkina Faso
| | - Sophie Houard
- European Vaccine Initiative (EVI), Universitäts Klinikum Heidelberg, Heidelberg, Germany
| | - Nobuko Arisue
- Department of Molecular Protozoology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Flavia D’Alessio
- European Vaccine Initiative (EVI), Universitäts Klinikum Heidelberg, Heidelberg, Germany
| | - Toshihiro Horii
- Department of Malaria Vaccine Development, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
- *Correspondence: Toshihiro Horii, ; Sodiomon B. Sirima,
| | - Sodiomon B. Sirima
- Groupe de Recherche Action en Santé, Ouagadougou (GRAS), Ouagadougou, Burkina Faso
- *Correspondence: Toshihiro Horii, ; Sodiomon B. Sirima,
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Immunosuppression in Malaria: Do Plasmodium falciparum Parasites Hijack the Host? Pathogens 2021; 10:pathogens10101277. [PMID: 34684226 PMCID: PMC8536967 DOI: 10.3390/pathogens10101277] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 12/13/2022] Open
Abstract
Malaria reflects not only a state of immune activation, but also a state of general immune defect or immunosuppression, of complex etiology that can last longer than the actual episode. Inhabitants of malaria-endemic regions with lifelong exposure to the parasite show an exhausted or immune regulatory profile compared to non- or minimally exposed subjects. Several studies and experiments to identify and characterize the cause of this malaria-related immunosuppression have shown that malaria suppresses humoral and cellular responses to both homologous (Plasmodium) and heterologous antigens (e.g., vaccines). However, neither the underlying mechanisms nor the relative involvement of different types of immune cells in immunosuppression during malaria is well understood. Moreover, the implication of the parasite during the different stages of the modulation of immunity has not been addressed in detail. There is growing evidence of a role of immune regulators and cellular components in malaria that may lead to immunosuppression that needs further research. In this review, we summarize the current evidence on how malaria parasites may directly and indirectly induce immunosuppression and investigate the potential role of specific cell types, effector molecules and other immunoregulatory factors.
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Harding CL, Villarino NF, Valente E, Schwarzer E, Schmidt NW. Plasmodium Impairs Antibacterial Innate Immunity to Systemic Infections in Part Through Hemozoin-Bound Bioactive Molecules. Front Cell Infect Microbiol 2020; 10:328. [PMID: 32714882 PMCID: PMC7344233 DOI: 10.3389/fcimb.2020.00328] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 05/29/2020] [Indexed: 01/02/2023] Open
Abstract
One complication of malaria is increased susceptibility to invasive bacterial infections. Plasmodium infections impair host immunity to non-Typhoid Salmonella (NTS) through heme-oxygenase I (HO-I)-induced release of immature granulocytes and myeloid cell-derived IL-10. Yet, it is not known if these mechanisms are specific to NTS. We show here, that Plasmodium yoelii 17XNL (Py) infected mice had impaired clearance of systemic Listeria monocytogenes (Lm) during both acute parasitemia and up to 2 months after clearance of Py infected red blood cells that was independent of HO-I and IL-10. Py-infected mice were also susceptible to Streptococcus pneumoniae (Sp) bacteremia, a common malaria-bacteria co-infection, with higher blood and spleen bacterial burdens and decreased survival compared to naïve mice. Mechanistically, impaired immunity to Sp was independent of HO-I, but was dependent on Py-induced IL-10. Splenic phagocytes from Py infected mice exhibit an impaired ability to restrict growth of intracellular Lm, and neutrophils from Py-infected mice produce less reactive oxygen species (ROS) in response to Lm or Sp. Analysis also identified a defect in a serum component in Py-infected mice that contributes to reduced production of ROS in response to Sp. Finally, treating naïve mice with Plasmodium-derived hemozoin containing naturally bound bioactive molecules, excluding DNA, impaired clearance of Lm. Collectively, we have demonstrated that Plasmodium infection impairs host immunity to diverse bacteria, including S. pneumoniae, through multiple effects on innate immunity, and that a parasite-specific factor (Hz+bound bioactive molecules) directly contributes to Plasmodium-induced suppression of antibacterial innate immunity.
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Affiliation(s)
- Christopher L Harding
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, United States
| | - Nicolas F Villarino
- Department of Veterinary Clinical Sciences, Washington State University, Pullman, WA, United States
| | - Elena Valente
- Department of Oncology, University of Torino, Turin, Italy
| | | | - Nathan W Schmidt
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, United States.,Ryan White Center for Pediatric Infectious Diseases and Global Health, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, United States
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Kijogi C, Kimura D, Bao LQ, Nakamura R, Chadeka EA, Cheruiyot NB, Bahati F, Yahata K, Kaneko O, Njenga SM, Ichinose Y, Hamano S, Yui K. Modulation of immune responses by Plasmodium falciparum infection in asymptomatic children living in the endemic region of Mbita, western Kenya. Parasitol Int 2018; 67:284-293. [PMID: 29353010 DOI: 10.1016/j.parint.2018.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 01/06/2018] [Accepted: 01/14/2018] [Indexed: 11/24/2022]
Abstract
Individuals living in malaria endemic areas become clinically immune after multiple re-infections over time and remain infected without apparent symptoms. However, it is unclear why a long period is required to gain clinical immunity to malaria, and how such immunity is maintained. Although malaria infection is reported to induce inhibition of immune responses, studies on asymptomatic individuals living in endemic regions of malaria are relatively scarce. We conducted a cross-sectional study of immune responses in asymptomatic school children aged 4-16years living in an area where Plasmodium falciparum and Schistosoma mansoni infections are co-endemic in Kenya. Peripheral blood mononuclear cells were subjected to flow cytometric analysis and cultured to determine proliferative responses and cytokine production. The proportions of cellular subsets in children positive for P. falciparum infection at the level of microscopy were comparable to the negative children, except for a reduction in central memory-phenotype CD8+ T cells and natural killer cells. In functional studies, the production of cytokines by peripheral blood mononuclear cells in response to P. falciparum crude antigens exhibited strong heterogeneity among children. In addition, production of IL-2 in response to anti-CD3 and anti-CD28 monoclonal antibodies was significantly reduced in P. falciparum-positive children as compared to -negative children, suggesting a state of unresponsiveness. These data suggest that the quality of T cell immune responses is heterogeneous among asymptomatic children living in the endemic region of P. falciparum, and that the responses are generally suppressed by active infection with Plasmodium parasites.
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Affiliation(s)
- Caroline Kijogi
- Division of Immunology, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Daisuke Kimura
- Division of Immunology, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Lam Quoc Bao
- Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University
| | - Risa Nakamura
- Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University
| | - Evans Asena Chadeka
- Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Nagasaki University Kenya Research Station, NUITM-KEMRI Project, Nairobi, Kenya
| | - Ngetich Benard Cheruiyot
- The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Nagasaki University Kenya Research Station, NUITM-KEMRI Project, Nairobi, Kenya
| | - Felix Bahati
- The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Nagasaki University Kenya Research Station, NUITM-KEMRI Project, Nairobi, Kenya
| | - Kazuhide Yahata
- The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Osamu Kaneko
- Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Sammy M Njenga
- Eastern and Southern Africa Centre of International Parasite Control (ESACIPAC), Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
| | - Yoshio Ichinose
- Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Nagasaki University Kenya Research Station, NUITM-KEMRI Project, Nairobi, Kenya
| | - Shinjiro Hamano
- Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University; Nagasaki University Kenya Research Station, NUITM-KEMRI Project, Nairobi, Kenya
| | - Katsuyuki Yui
- Division of Immunology, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Program for Nurturing Global Leaders in Tropical and Emerging Infectious Diseases, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
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5
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Rautenbach Y, Goddard A, Thompson PN, Mellanby RJ, Leisewitz AL. A flow cytometric assessment of the lymphocyte immunophenotypes in dogs naturally infected with Babesia rossi. Vet Parasitol 2017; 241:26-34. [PMID: 28579026 DOI: 10.1016/j.vetpar.2017.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/20/2017] [Accepted: 05/06/2017] [Indexed: 11/28/2022]
Abstract
Immunity to Babesia infection requires both innate and acquired responses, including cell mediated- and humoral responses. The aims of this study were to investigate the variation in selected peripheral blood lymphocyte phenotypes in dogs with virulent babesiosis at presentation and over time after treatment, and to determine whether these were correlated with the severity of clinical signs. Forty-four dogs naturally infected with B. rossi were studied and 5 healthy dogs were included as controls. Blood samples were collected from the jugular vein at admission, prior to any treatment, and at 24h and 48-72h. Leukocytes were incubated with canine specific, fluorochrome conjugated anti-CD3, anti-CD4, anti-CD8, and anti-B cell markers. Babesia-infected dogs were divided into complicated or uncomplicated groups on clinical grounds and in-house laboratory assays. The percentage CD3+ lymphocytes in the complicated group was lower compared to the controls (P=0.014) and uncomplicated group (P=0.007). The percentage CD4+ T lymphocytes in the complicated group was lower compared to the controls (P=0.027) and uncomplicated group (P=0.014). Both the complicated as well as the uncomplicated groups expressed a lower percentage CD8+ T lymphocytes compared to the control group (P<0.001 and P=0.005, respectively). The percentage B lymphocytes was higher in the complicated group at 48-72h. These findings could indicate the presence of a functional immune suppression secondary to increased apoptosis or redistribution of effector lymphocytes and/or a combination of other immune modulatory mechanisms induced by B. rossi infection.
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Affiliation(s)
- Yolandi Rautenbach
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa.
| | - Amelia Goddard
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | - Peter N Thompson
- Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | - Richard J Mellanby
- The Royal (Dick) School of Veterinary Studies and The Roslin Institute, Department of Veterinary Clinical Sciences, University of Edinburgh, Roslin, Midlothian, Scotland, United Kingdom
| | - Andrew L Leisewitz
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
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6
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Abstract
Epstein-Barr virus (EBV) infection is associated with several distinct hematological and epithelial malignancies, e.g., Burkitt lymphoma, Hodgkin lymphoma, nasopharyngeal carcinoma, gastric carcinoma, and others. The association with several malignant tumors of local and worldwide distribution makes EBV one of the most important tumor viruses. Furthermore, because EBV can cause posttransplant lymphoproliferative disease, transplant medicine has to deal with EBV as a major pathogenic virus second only to cytomegalovirus. In this review, we summarize briefly the natural history of EBV infection and outline some of the recent advances in the pathogenesis of the major EBV-associated neoplasms. We present alternative scenarios and discuss them in the light of most recent experimental data. Emerging research areas including EBV-induced patho-epigenetic alterations in host cells and the putative role of exosome-mediated information transfer in disease development are also within the scope of this review. This book contains an in-depth description of a series of modern methodologies used in EBV research. In this introductory chapter, we thoroughly refer to the applications of these methods and demonstrate how they contributed to the understanding of EBV-host cell interactions. The data gathered using recent technological advancements in molecular biology and immunology as well as the application of sophisticated in vitro and in vivo experimental models certainly provided deep and novel insights into the pathogenetic mechanisms of EBV infection and EBV-associated tumorigenesis. Furthermore, the development of adoptive T cell immunotherapy has provided a novel approach to the therapy of viral disease in transplant medicine and hematology.
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Affiliation(s)
- Janos Minarovits
- Faculty of Dentistry, Department of Oral Biology and Experimental Dental Research, University of Szeged, Tisza Lajos krt. 64, H-6720, Szeged, Hungary.
| | - Hans Helmut Niller
- Institute of Medical Microbiology and Hygiene, University of Regensburg, D-93053, Regensburg, Germany
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Mackroth MS, Abel A, Steeg C, Schulze zur Wiesch J, Jacobs T. Acute Malaria Induces PD1+CTLA4+ Effector T Cells with Cell-Extrinsic Suppressor Function. PLoS Pathog 2016; 12:e1005909. [PMID: 27802341 PMCID: PMC5089727 DOI: 10.1371/journal.ppat.1005909] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 09/01/2016] [Indexed: 12/15/2022] Open
Abstract
In acute Plasmodium falciparum (P. falciparum) malaria, the pro- and anti-inflammatory immune pathways must be delicately balanced so that the parasitemia is controlled without inducing immunopathology. An important mechanism to fine-tune T cell responses in the periphery is the induction of coinhibitory receptors such as CTLA4 and PD1. However, their role in acute infections such as P. falciparum malaria remains poorly understood. To test whether coinhibitory receptors modulate CD4+ T cell functions in malaria, blood samples were obtained from patients with acute P. falciparum malaria treated in Germany. Flow cytometric analysis showed a more frequent expression of CTLA4 and PD1 on CD4+ T cells of malaria patients than of healthy control subjects. In vitro stimulation with P. falciparum-infected red blood cells revealed a distinct population of PD1+CTLA4+CD4+ T cells that simultaneously produced IFNγ and IL10. This antigen-specific cytokine production was enhanced by blocking PD1/PDL1 and CTLA4. PD1+CTLA4+CD4+ T cells were further isolated based on surface expression of PD1 and their inhibitory function investigated in-vitro. Isolated PD1+CTLA4+CD4+ T cells suppressed the proliferation of the total CD4+ population in response to anti-CD3/28 and plasmodial antigens in a cell-extrinsic manner. The response to other specific antigens was not suppressed. Thus, acute P. falciparum malaria induces P. falciparum-specific PD1+CTLA4+CD4+ Teffector cells that coproduce IFNγ and IL10, and inhibit other CD4+ T cells. Transient induction of regulatory Teffector cells may be an important mechanism that controls T cell responses and might prevent severe inflammation in patients with malaria and potentially other acute infections.
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Affiliation(s)
- Maria Sophia Mackroth
- Department of Medicine I, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
- Department of Immunology, Bernhard-Nocht-Institute of Tropical Medicine, Hamburg, Germany
| | - Annemieke Abel
- Department of Immunology, Bernhard-Nocht-Institute of Tropical Medicine, Hamburg, Germany
| | - Christiane Steeg
- Department of Immunology, Bernhard-Nocht-Institute of Tropical Medicine, Hamburg, Germany
| | | | - Thomas Jacobs
- Department of Immunology, Bernhard-Nocht-Institute of Tropical Medicine, Hamburg, Germany
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Van Braeckel-Budimir N, Kurup SP, Harty JT. Regulatory issues in immunity to liver and blood-stage malaria. Curr Opin Immunol 2016; 42:91-97. [PMID: 27351448 DOI: 10.1016/j.coi.2016.06.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/10/2016] [Accepted: 06/15/2016] [Indexed: 02/01/2023]
Abstract
T cells play a major role in control of both blood and liver stage of plasmodium infection. While immunization with certain attenuated whole-parasite vaccines that are attenuated at the liver stage of the infection induces protective T cell responses, even multiple exposures to natural infection in endemic areas do not lead to stable T cell memory or humoral immunity and sterilizing protection. One of the key differences between vaccination and natural exposure is the absence of blood stage during vaccination. Here we will discuss possible immunoregulatory strategies employed by blood stage of malaria leading to generation of severely compromised T cell and humoral immune responses and subsequent lack of sterilizing immunity.
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Affiliation(s)
| | - Samarchith P Kurup
- Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA
| | - John T Harty
- Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA; Department of Pathology, University of Iowa, Iowa City, IA 52242, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, USA.
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Mooney JP, Lee SJ, Lokken KL, Nanton MR, Nuccio SP, McSorley SJ, Tsolis RM. Transient Loss of Protection Afforded by a Live Attenuated Non-typhoidal Salmonella Vaccine in Mice Co-infected with Malaria. PLoS Negl Trop Dis 2015; 9:e0004027. [PMID: 26366739 PMCID: PMC4569369 DOI: 10.1371/journal.pntd.0004027] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 08/03/2015] [Indexed: 11/19/2022] Open
Abstract
In immunocompetent individuals, non-typhoidal Salmonella serovars (NTS) are associated with gastroenteritis, however, there is currently an epidemic of NTS bloodstream infections in sub-Saharan Africa. Plasmodium falciparum malaria is an important risk factor for invasive NTS bloodstream in African children. Here we investigated whether a live, attenuated Salmonella vaccine could be protective in mice, in the setting of concurrent malaria. Surprisingly, mice acutely infected with the nonlethal malaria parasite Plasmodium yoelii 17XNL exhibited a profound loss of protective immunity to NTS, but vaccine-mediated protection was restored after resolution of malaria. Absence of protective immunity during acute malaria correlated with maintenance of antibodies to NTS, but a marked reduction in effector capability of Salmonella-specific CD4 and CD8 T cells. Further, increased expression of the inhibitory molecule PD1 was identified on memory CD4 T cells induced by vaccination. Blockade of IL-10 restored protection against S. Typhimurium, without restoring CD4 T cell effector function. Simultaneous blockade of CTLA-4, LAG3, and PDL1 restored IFN-γ production by vaccine-induced memory CD4 T cells but was not sufficient to restore protection. Together, these data demonstrate that malaria parasite infection induces a temporary loss of an established adaptive immune response via multiple mechanisms, and suggest that in the setting of acute malaria, protection against NTS mediated by live vaccines may be interrupted. In children, malaria is a predisposing factor for invasive bacterial infections with non-typhoidal Salmonella (NTS) serovars, a frequent cause of morbidity and mortality in sub-Saharan Africa. Since development of vaccines against NTS has been proposed as a strategy to protect African children against disseminated NTS infection, we interrogated the effect of malaria on vaccine-induced memory responses to NTS. Our results from a mouse infection model show that infection with malaria parasites temporarily suspends protective immunity conferred by a live, attenuated vaccine and suppresses adaptive immune responses to NTS that are mediated by T cells. These results suggest that in the setting of acute malaria, live attenuated NTS vaccines may lose their effectiveness.
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Affiliation(s)
- Jason P. Mooney
- Department of Microbiology & Immunology, School of Medicine, University of California Davis, Davis, California, United States of America
| | - Seung-Joo Lee
- Center for Comparative Medicine, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Kristen L. Lokken
- Department of Microbiology & Immunology, School of Medicine, University of California Davis, Davis, California, United States of America
| | - Minelva R. Nanton
- Center for Comparative Medicine, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Sean-Paul Nuccio
- Department of Microbiology & Immunology, School of Medicine, University of California Davis, Davis, California, United States of America
| | - Stephen J. McSorley
- Center for Comparative Medicine, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Renée M. Tsolis
- Department of Microbiology & Immunology, School of Medicine, University of California Davis, Davis, California, United States of America
- * E-mail:
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