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Plasmodium falciparum PfEMP1 Modulates Monocyte/Macrophage Transcription Factor Activation and Cytokine and Chemokine Responses. Infect Immun 2017; 86:IAI.00447-17. [PMID: 29038124 PMCID: PMC5736827 DOI: 10.1128/iai.00447-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/03/2017] [Indexed: 12/11/2022] Open
Abstract
Immunity to Plasmodium falciparum malaria is slow to develop, and it is often asserted that malaria suppresses host immunity, although this is poorly understood and the molecular basis for such activity remains unknown. P. falciparum erythrocyte membrane protein 1 (PfEMP1) is a virulence factor that plays a key role in parasite-host interactions. We investigated the immunosuppressive effect of PfEMP1 on monocytes/macrophages, which are central to the antiparasitic innate response. RAW macrophages and human primary monocytes were stimulated with wild-type 3D7 or CS2 parasites or transgenic PfEMP1-null parasites. To study the immunomodulatory effect of PfEMP1, transcription factor activation and cytokine and chemokine responses were measured. The level of activation of NF-κB was significantly lower in macrophages stimulated with parasites that express PfEMP1 at the red blood cell surface membrane than in macrophages stimulated with PfEMP1-null parasites. Modulation of additional transcription factors, including CREB, also occurred, resulting in reduced immune gene expression and decreased tumor necrosis factor (TNF) and interleukin-10 (IL-10) release. Similarly, human monocytes released less IL-1β, IL-6, IL-10, monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 1α (MIP-1α), MIP-1β, and TNF specifically in response to VAR2CSA PfEMP1-containing parasites than in response to PfEMP1-null parasites, suggesting that this immune regulation by PfEMP1 is important in naturally occurring infections. These results indicate that PfEMP1 is an immunomodulatory molecule that affects the activation of a range of transcription factors, dampening cytokine and chemokine responses. Therefore, these findings describe a potential molecular basis for immune suppression by P. falciparum.
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52
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Jagannathan P, Lutwama F, Boyle MJ, Nankya F, Farrington LA, McIntyre TI, Bowen K, Naluwu K, Nalubega M, Musinguzi K, Sikyomu E, Budker R, Katureebe A, Rek J, Greenhouse B, Dorsey G, Kamya MR, Feeney ME. Vδ2+ T cell response to malaria correlates with protection from infection but is attenuated with repeated exposure. Sci Rep 2017; 7:11487. [PMID: 28904345 PMCID: PMC5597587 DOI: 10.1038/s41598-017-10624-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 08/11/2017] [Indexed: 12/20/2022] Open
Abstract
Vδ2+ γδ T cells are semi-innate T cells that expand markedly following P. falciparum (Pf) infection in naïve adults, but are lost and become dysfunctional among children repeatedly exposed to malaria. The role of these cells in mediating clinical immunity (i.e. protection against symptoms) to malaria remains unclear. We measured Vδ2+ T cell absolute counts at acute and convalescent malaria timepoints (n = 43), and Vδ2+ counts, cellular phenotype, and cytokine production following in vitro stimulation at asymptomatic visits (n = 377), among children aged 6 months to 10 years living in Uganda. Increasing age was associated with diminished in vivo expansion following malaria, and lower Vδ2 absolute counts overall, among children living in a high transmission setting. Microscopic parasitemia and expression of the immunoregulatory markers Tim-3 and CD57 were associated with diminished Vδ2+ T cell pro-inflammatory cytokine production. Higher Vδ2 pro-inflammatory cytokine production was associated with protection from subsequent Pf infection, but also with an increased odds of symptoms once infected. Vδ2+ T cells may play a role in preventing malaria infection in children living in endemic settings; progressive loss and dysfunction of these cells may represent a disease tolerance mechanism that contributes to the development of clinical immunity to malaria.
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Affiliation(s)
- Prasanna Jagannathan
- Department of Medicine, Stanford University, Stanford, CA, USA.
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA.
| | - Fredrick Lutwama
- Infectious Diseases Institute, Kampala, Uganda
- Makerere University College of Health Sciences, Kampala, Uganda
| | - Michelle J Boyle
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
- Burnet Institute, Disease Elimination (Malaria), Melbourne, Australia
| | | | - Lila A Farrington
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Tara I McIntyre
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Katherine Bowen
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Kate Naluwu
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | - Esther Sikyomu
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Rachel Budker
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | | | - John Rek
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Bryan Greenhouse
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Grant Dorsey
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Moses R Kamya
- Makerere University College of Health Sciences, Kampala, Uganda
| | - Margaret E Feeney
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA.
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA.
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53
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Schofield L, Ioannidis LJ, Karl S, Robinson LJ, Tan QY, Poole DP, Betuela I, Hill DL, Siba PM, Hansen DS, Mueller I, Eriksson EM. Synergistic effect of IL-12 and IL-18 induces TIM3 regulation of γδ T cell function and decreases the risk of clinical malaria in children living in Papua New Guinea. BMC Med 2017; 15:114. [PMID: 28615061 PMCID: PMC5471992 DOI: 10.1186/s12916-017-0883-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Accepted: 05/22/2017] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND γδ T cells are important for both protective immunity and immunopathogenesis during malaria infection. However, the immunological processes determining beneficial or detrimental effects on disease outcome remain elusive. The aim of this study was to examine expression and regulatory effect of the inhibitory receptor T-cell immunoglobulin domain and mucin domain 3 (TIM3) on γδ T cells. While TIM3 expression and function on conventional αβ T cells have been clearly defined, the equivalent characterization on γδ T cells and associations with disease outcomes is limited. This study investigated the functional capacity of TIM3+ γδ T cells and the underlying mechanisms contributing to TIM3 upregulation and established an association with malaria disease outcomes. METHODS We analyzed TIM3 expression on γδ T cells in 132 children aged 5-10 years living in malaria endemic areas of Papua New Guinea. TIM3 upregulation and effector functions of TIM3+ γδ T cells were assessed following in vitro stimulation with parasite-infected erythrocytes, phosphoantigen and/or cytokines. Associations between the proportion of TIM3-expressing cells and the molecular force of infection were tested using negative binomial regression and in a Cox proportional hazards model for time to first clinical episode. Multivariable analyses to determine the association of TIM3 and IL-18 levels were conducted using general linear models. Malaria infection mouse models were utilized to experimentally investigate the relationship between repeated exposure and TIM3 upregulation. RESULTS This study demonstrates that even in the absence of an active malaria infection, children of malaria endemic areas have an atypical population of TIM3-expressing γδ T cells (mean frequency TIM3+ of total γδ T cells 15.2% ± 12). Crucial factors required for γδ T cell TIM3 upregulation include IL-12/IL-18, and plasma IL-18 was associated with TIM3 expression (P = 0.002). Additionally, we show a relationship between TIM3 expression and infection with distinct parasite clones during repeated exposure. TIM3+ γδ T cells were functionally impaired and were associated with asymptomatic malaria infection (hazard ratio 0.54, P = 0.032). CONCLUSIONS Collectively our data demonstrate a novel role for IL-12/IL-18 in shaping the innate immune response and provide fundamental insight into aspects of γδ T cell immunoregulation. Furthermore, we show that TIM3 represents an important γδ T cell regulatory component involved in minimizing malaria symptoms.
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Affiliation(s)
- Louis Schofield
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, QLD, 4811, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Lisa J Ioannidis
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Stephan Karl
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Leanne J Robinson
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia.,Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea.,Burnet Institute, Melbourne, VIC, 3004, Australia
| | - Qiao Y Tan
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Daniel P Poole
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, 3052, Australia.,Department of Anatomy and Neuroscience, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Inoni Betuela
- Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea
| | - Danika L Hill
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea.,School of Veterinary and Biomedical Sciences, James Cook University, Townsville, QLD, 4811, Australia
| | - Diana S Hansen
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Emily M Eriksson
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia. .,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia. .,The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC, 3052, Australia.
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Ifeanyichukwu MO, Okamgba OC, Amilo GI, Nwokorie EA. PERIPHERAL PARASITAEMIA AND ITS ASSOCIATION WITH PLASMA CYTOKINES LEVELS IN MALARIA-INFECTED PREGNANT WOMEN IN ABA, ABIA STATE, NIGERIA. Afr J Infect Dis 2017; 11:54-61. [PMID: 28670640 PMCID: PMC5476813 DOI: 10.21010/ajid.v11i2.7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background: Cytokines in pregnant female may not be a normal phenomenon as malarial infection is often associated with strong CD4+ cell activation and up-regulation of pro-inflammatory cytokines. We investigated the relationship between peripheral parasitaemia and plasma levels of cytokines among malaria infected pregnant women in Aba, Abia State, Nigeria. Materials and Methods: A total of 206 non-HIV positive asymptomatic malaria parasitaemic (n=144) and non-parasitaemic (n=62) pregnant women were recruited for this study alongside 80 non-pregnant women who served as positive (n=40) and negative (n=40) controls. Blood samples were aseptically collected from each subject and tested for HIV and malaria parasites using standard methods. Also, plasma levels of cytokines were measured using Th1/Th2 human cytokine ELISA kits (Abcam, UK). Analysis of Variance and Student’s t-test were used for Comparison of groups while Pearson’s Correlation Coefficient was used for tests of association. Results: The results revealed a mean parasite density of 685.56±484.55 parasites/µl of blood. Malaria infected pregnant subjects showed significantly higher levels of IFN-γ, TNF-α, IL-4, IL-6 and IL-10 when compared with their non-infected counterparts (P< 0.05). The cytokines evaluated were higher in moderate parasitaemia than mild parasitaemia. Positive correlation existed between peripheral parasite density (PPD) and IL-4 (r= 0.24, P=0.004), PPD and IL-6 (r = 0.35, P = 0.001) as well as PPD and IL-10 (r = 0.29, P = 0.001). Conclusion: This study showed that increase in peripheral parasitaemia increased levels of some plasma cytokines (IL-4, IL-6 and IL-10) but not IFN-γ and TNF-α in the malaria infected pregnant women studied.
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Affiliation(s)
- M O Ifeanyichukwu
- Department of Medical Laboratory Science, Faculty of Health Sciences and Technology, Nnamdi Azikwe University, Nnewi Campus, Nnewi, Nigeria
| | - O C Okamgba
- Department of Medical Laboratory Science, Faculty of Health Sciences and Technology, Nnamdi Azikwe University, Nnewi Campus, Nnewi, Nigeria
| | - G I Amilo
- Department of Haematology, Faculty of Medicine, Nnamdi Azikwe University, Nnewi Campus, Nnewi, Nigeria
| | - E A Nwokorie
- Michael Okpara University of Agriculture, Umudike, Umuahia, Abia State, Nigeria
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55
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Mpina M, Maurice NJ, Yajima M, Slichter CK, Miller HW, Dutta M, McElrath MJ, Stuart KD, De Rosa SC, McNevin JP, Linsley PS, Abdulla S, Tanner M, Hoffman SL, Gottardo R, Daubenberger CA, Prlic M. Controlled Human Malaria Infection Leads to Long-Lasting Changes in Innate and Innate-like Lymphocyte Populations. THE JOURNAL OF IMMUNOLOGY 2017; 199:107-118. [PMID: 28576979 DOI: 10.4049/jimmunol.1601989] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 05/01/2017] [Indexed: 11/19/2022]
Abstract
Animal model studies highlight the role of innate-like lymphocyte populations in the early inflammatory response and subsequent parasite control following Plasmodium infection. IFN-γ production by these lymphocytes likely plays a key role in the early control of the parasite and disease severity. Analyzing human innate-like T cell and NK cell responses following infection with Plasmodium has been challenging because the early stages of infection are clinically silent. To overcome this limitation, we examined blood samples from a controlled human malaria infection (CHMI) study in a Tanzanian cohort, in which volunteers underwent CHMI with a low or high dose of Plasmodium falciparum sporozoites. The CHMI differentially affected NK, NKT (invariant NKT), and mucosal-associated invariant T cell populations in a dose-dependent manner, resulting in an altered composition of this innate-like lymphocyte compartment. Although these innate-like responses are typically thought of as short-lived, we found that changes persisted for months after the infection was cleared, leading to significantly increased frequencies of mucosal-associated invariant T cells 6 mo postinfection. We used single-cell RNA sequencing and TCR αβ-chain usage analysis to define potential mechanisms for this expansion. These single-cell data suggest that this increase was mediated by homeostatic expansion-like mechanisms. Together, these data demonstrate that CHMI leads to previously unappreciated long-lasting alterations in the human innate-like lymphocyte compartment. We discuss the consequences of these changes for recurrent parasite infection and infection-associated pathologies and highlight the importance of considering host immunity and infection history for vaccine design.
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Affiliation(s)
- Maxmillian Mpina
- Clinical Immunology Unit, Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, Basel, 4001 Switzerland
| | - Nicholas J Maurice
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - Masanao Yajima
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109.,Department of Mathematics and Statistics, Boston University, Boston, MA 02215
| | - Chloe K Slichter
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109.,Department of Global Health, University of Washington, Seattle, WA 98195
| | - Hannah W Miller
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - Mukta Dutta
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - M Juliana McElrath
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109.,Department of Global Health, University of Washington, Seattle, WA 98195
| | | | - Stephen C De Rosa
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - John P McNevin
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | | | - Salim Abdulla
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, Tanzania; and
| | - Marcel Tanner
- Clinical Immunology Unit, Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, Basel, 4001 Switzerland
| | | | - Raphael Gottardo
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - Claudia A Daubenberger
- Clinical Immunology Unit, Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland; .,University of Basel, Basel, 4001 Switzerland
| | - Martin Prlic
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; .,Department of Global Health, University of Washington, Seattle, WA 98195
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56
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Cheng Y, Wang B, Changrob S, Han JH, Sattabongkot J, Ha KS, Chootong P, Lu F, Cao J, Nyunt MH, Park WS, Hong SH, Lim CS, Tsuboi T, Han ET. Naturally acquired humoral and cellular immune responses to Plasmodium vivax merozoite surface protein 8 in patients with P. vivax infection. Malar J 2017; 16:211. [PMID: 28532483 PMCID: PMC5440977 DOI: 10.1186/s12936-017-1837-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 04/26/2017] [Indexed: 11/13/2022] Open
Abstract
Background Thirty-one glycosylphosphatidylinositol (GPI)-anchored proteins of Plasmodium vivax, merozoite surface protein 1 (MSP1), MSP1 paralogue, MSP4, MSP5, MSP8, and MSP10 have been reported from homologs of Plasmodium falciparum by gene annotation with bioinformatics tools. These GPI-anchored proteins contain two epidermal growth factor (EGF)-like domains at its C-terminus. Here, P. vivax merozoite surface protein 8 (PvMSP8) are considered as potential targets of protective immunity. Methods Recombinant PvMSP8 (rPvMSP8) was expressed, purified, and used for the assessment of humoral and cellular immune responses in P. vivax-infected patients and immune mice. Moreover, the target epitope of ant-PvMSP8 antibodies and subcellular localization of PvMSP8 was also determined. Results The rPvMSP8 was successfully expressed and purified as soluble form as ~55 kDa. PvMSP8 was localized to the outer circle of pigments associated with the food vacuole. The rPvMSP8 protein had a high antigenicity (73.2% in sensitivity and 96.2% in specificity) in patients infected with P. vivax. IgG2 antibody subtype was the predominantly responses to this antigen. Antibody response to PvMSP8 increased up to day 7 and after that slightly decreased within a month. The longevity of anti-PvMSP8 antibody was stably sustained up to 12-year recovery patient samples. Most anti-PvMSP8 antibodies recognized two epitopes that were located outside the C-terminal EGF-like domain. The cellular immune response in P. vivax-exposed individuals produced high levels of IFN-γ and IL-10 upon PvMSP8 antigen stimulation in vitro. Conclusions All data in this study suggest that PvMSP8 antigen has a potential to induce both humoral and cellular immune responses in patients with P. vivax infection. The subcellular localization of PvMSP8 confirmed that it was associated with the parasite food vacuole in blood-stage parasites. A further characterization of this protein will be useful for blood stage P. vivax vaccine development. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1837-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yang Cheng
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea.,Department of Parasitology, Wuxi Medical School, Jiangnan University, Wuxi, Jiangsu, China
| | - Bo Wang
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea.,Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Siriruk Changrob
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, 10700, Thailand
| | - Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Kwon-Soo Ha
- Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea
| | - Patchanee Chootong
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, 10700, Thailand
| | - Feng Lu
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea.,Key Laboratory of Parasitic Disease Control and Prevention (Ministry of Health), and Jiangsu Provincial Key Laboratory of Parasite Molecular Biology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu Province, People's Republic of China
| | - Jun Cao
- Key Laboratory of Parasitic Disease Control and Prevention (Ministry of Health), and Jiangsu Provincial Key Laboratory of Parasite Molecular Biology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu Province, People's Republic of China
| | - Myat Htut Nyunt
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea.,Department of Medical Research, Yangon, Myanmar
| | - Won Sun Park
- Department of Physiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea
| | - Seok-Ho Hong
- Department of Internal Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea
| | - Chae Seung Lim
- Department of Laboratory Medicine, College of Medicine, Korea University, Seoul, Republic of Korea
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Eun-Taek Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-701, Republic of Korea.
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Acharya P, Garg M, Kumar P, Munjal A, Raja KD. Host-Parasite Interactions in Human Malaria: Clinical Implications of Basic Research. Front Microbiol 2017; 8:889. [PMID: 28572796 PMCID: PMC5435807 DOI: 10.3389/fmicb.2017.00889] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 05/02/2017] [Indexed: 12/21/2022] Open
Abstract
The malaria parasite, Plasmodium, is one of the oldest parasites documented to infect humans and has proven particularly hard to eradicate. One of the major hurdles in designing an effective subunit vaccine against the malaria parasite is the insufficient understanding of host–parasite interactions within the human host during infections. The success of the parasite lies in its ability to evade the human immune system and recruit host responses as physiological cues to regulate its life cycle, leading to rapid acclimatization of the parasite to its immediate host environment. Hence understanding the environmental niche of the parasite is crucial in developing strategies to combat this deadly infectious disease. It has been increasingly recognized that interactions between parasite proteins and host factors are essential to establishing infection and virulence at every stage of the parasite life cycle. This review reassesses all of these interactions and discusses their clinical importance in designing therapeutic approaches such as design of novel vaccines. The interactions have been followed from the initial stages of introduction of the parasite under the human dermis until asexual and sexual blood stages which are essential for transmission of malaria. We further classify the interactions as “direct” or “indirect” depending upon their demonstrated ability to mediate direct physical interactions of the parasite with host factors or their indirect manipulation of the host immune system since both forms of interactions are known to have a crucial role during infections. We also discuss the many ways in which this understanding has been taken to the field and the success of these strategies in controlling human malaria.
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Affiliation(s)
- Pragyan Acharya
- Department of Biochemistry, All India Institute of Medical SciencesNew Delhi, India
| | - Manika Garg
- Department of Biochemistry, Jamia Hamdard UniversityNew Delhi, India
| | - Praveen Kumar
- Department of Biochemistry, All India Institute of Medical SciencesNew Delhi, India
| | - Akshay Munjal
- Department of Biochemistry, All India Institute of Medical SciencesNew Delhi, India
| | - K D Raja
- Department of Biochemistry, All India Institute of Medical SciencesNew Delhi, India
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T cell subtypes and reciprocal inflammatory mediator expression differentiate P. falciparum memory recall responses in asymptomatic and symptomatic malaria patients in southeastern Haiti. PLoS One 2017; 12:e0174718. [PMID: 28369062 PMCID: PMC5378365 DOI: 10.1371/journal.pone.0174718] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 03/14/2017] [Indexed: 12/20/2022] Open
Abstract
Asymptomatic Plasmodium falciparum infection is responsible for maintaining malarial disease within human populations in low transmission countries such as Haiti. Investigating differential host immune responses to the parasite as a potential underlying mechanism could help provide insight into this highly complex phenomenon and possibly identify asymptomatic individuals. We performed a cross-sectional analysis of individuals who were diagnosed with malaria in Sud-Est, Haiti by comparing the cellular and humoral responses of both symptomatic and asymptomatic subjects. Plasma samples were analyzed with a P. falciparum protein microarray, which demonstrated serologic reactivity to 3,877 P. falciparum proteins of known serologic reactivity; however, no antigen-antibody reactions delineating asymptomatics from symptomatics were identified. In contrast, differences in cellular responses were observed. Flow cytometric analysis of patient peripheral blood mononuclear cells co-cultured with P. falciparum infected erythrocytes demonstrated a statistically significant increase in the proportion of T regulatory cells (CD4+ CD25+ CD127-), and increases in unique populations of both NKT-like cells (CD3+ CD8+ CD56+) and CD8mid T cells in asymptomatics compared to symptomatics. Also, CD38+/HLA-DR+ expression on γδ T cells, CD8mid (CD56-) T cells, and CD8mid CD56+ NKT-like cells decreased upon exposure to infected erythrocytes in both groups. Cytometric bead analysis of the co-culture supernatants demonstrated an upregulation of monocyte-activating chemokines/cytokines in asymptomatics, while immunomodulatory soluble factors were elevated in symptomatics. Principal component analysis of these expression values revealed a distinct clustering of individual responses within their respective phenotypic groups. This is the first comprehensive investigation of immune responses to P. falciparum in Haiti, and describes unique cell-mediated immune repertoires that delineate individuals into asymptomatic and symptomatic phenotypes. Future investigations using large scale biological data sets analyzing multiple components of adaptive immunity, could collectively define which cellular responses and molecular correlates of disease outcome are malaria region specific, and which are truly generalizable features of asymptomatic Plasmodium immunity, a research goal of critical priority.
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59
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Adukpo S, Gyan BA, Ofori MF, Dodoo D, Velavan TP, Meyer CG. Triggering receptor expressed on myeloid cells 1 (TREM-1) and cytokine gene variants in complicated and uncomplicated malaria. Trop Med Int Health 2016; 21:1592-1601. [PMID: 27671831 DOI: 10.1111/tmi.12787] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Malaria elicits inflammatory responses, which, if not well regulated, may exert detrimental effects. When activated, triggering receptor expressed on myeloid cells 1 (TREM-1) enhances inflammatory responses by increasing secretion of IL-8 and other Th1 cytokines. In contrast, TREM-like transcript 1 (TREML-1) promotes anti-inflammatory responses by binding to TREM-1 ligands and competing with TREM-1, thus antagonizing TREM-1 activation to reduce inflammation. Endothelial protein C receptor (EPCR) also mediates anti-inflammatory responses by activating endothelial protein C (PC). Upon microbial stimulation, soluble forms of TREM-1 (sTREM-1) and soluble EPCR (sEPCR) are released. Their plasma levels reflect the degree of inflammation and the severity of infection. METHODS In a cross-sectional study comparing patients with severe with uncomplicated malaria, sTREM-1, soluble TREML-1 (sTREML-1) and sEPCR plasma levels as well as plasma levels of sEPCR derived from convalescent patients were quantified. Samples were collected on admittance of paediatric patients infected with Plasmodium falciparum to hospitals in Accra, Ghana. Distinct genetic regions of the genes encoding TREM-1, EPCR, interleukin (IL)-8 and IL-18 encompassing known genetic polymorphisms that influence plasma levels underwent DNA sequencing. RESULTS Higher sTREM-1 levels were observed among children suffering from severe malaria compared to those with uncomplicated malaria (P = 0.049). Low TREM-1 to TREML-1 ratios were associated with uncomplicated malaria (P = 0.033). The TREM1 rs2234237T variant causing the amino acid exchange Thr25Ser, which has been associated with higher TREM-1 plasma levels, was significantly more frequent among patients with severe malaria than in those with uncomplicated malaria (P = 0.036). Low levels of sEPCR were observed in severe and uncomplicated malaria, while variant genotypes of IL8, IL18 and EPCR did not show any association. CONCLUSION Higher plasma levels of sTREM-1 alone or relative to sTREML-1 during malaria predispose to the phenotype of severe malaria. Carriage of the TREM1 rs2234237T allele appears to be a risk factor for the development of severe malaria.
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Affiliation(s)
- Selorme Adukpo
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Ben A Gyan
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Michael F Ofori
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Daniel Dodoo
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Thirumalaisamy P Velavan
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Fondation Congolaise pour la Recherche Médicale, Brazzaville, Republic of Congo.,Duy Tan University, Da Nang, Vietnam
| | - Christian G Meyer
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Duy Tan University, Da Nang, Vietnam
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Requena P, Rui E, Padilla N, Martínez-Espinosa FE, Castellanos ME, Bôtto-Menezes C, Malheiro A, Arévalo-Herrera M, Kochar S, Kochar SK, Kochar DK, Umbers AJ, Ome-Kaius M, Wangnapi R, Hans D, Menegon M, Mateo F, Sanz S, Desai M, Mayor A, Chitnis CC, Bardají A, Mueller I, Rogerson S, Severini C, Fernández-Becerra C, Menéndez C, del Portillo H, Dobaño C. Plasmodium vivax VIR Proteins Are Targets of Naturally-Acquired Antibody and T Cell Immune Responses to Malaria in Pregnant Women. PLoS Negl Trop Dis 2016; 10:e0005009. [PMID: 27711158 PMCID: PMC5053494 DOI: 10.1371/journal.pntd.0005009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 08/29/2016] [Indexed: 11/19/2022] Open
Abstract
P. vivax infection during pregnancy has been associated with poor outcomes such as anemia, low birth weight and congenital malaria, thus representing an important global health problem. However, no vaccine is currently available for its prevention. Vir genes were the first putative virulent factors associated with P. vivax infections, yet very few studies have examined their potential role as targets of immunity. We investigated the immunogenic properties of five VIR proteins and two long synthetic peptides containing conserved VIR sequences (PvLP1 and PvLP2) in the context of the PregVax cohort study including women from five malaria endemic countries: Brazil, Colombia, Guatemala, India and Papua New Guinea (PNG) at different timepoints during and after pregnancy. Antibody responses against all antigens were detected in all populations, with PNG women presenting the highest levels overall. P. vivax infection at sample collection time was positively associated with antibody levels against PvLP1 (fold-increase: 1.60 at recruitment -first antenatal visit-) and PvLP2 (fold-increase: 1.63 at delivery), and P. falciparum co-infection was found to increase those responses (for PvLP1 at recruitment, fold-increase: 2.25). Levels of IgG against two VIR proteins at delivery were associated with higher birth weight (27 g increase per duplicating antibody levels, p<0.05). Peripheral blood mononuclear cells from PNG uninfected pregnant women had significantly higher antigen-specific IFN-γ TH1 responses (p=0.006) and secreted less pro-inflammatory cytokines TNF and IL-6 after PvLP2 stimulation than P. vivax-infected women (p<0.05). These data demonstrate that VIR antigens induce the natural acquisition of antibody and T cell memory responses that might be important in immunity to P. vivax during pregnancy in very diverse geographical settings. Naturally-acquired antibody responses to novel recombinant proteins and synthetic peptides based on sequences from P. vivax VIR antigens were evaluated in women from five distinct geographical regions endemic for malaria, during and after pregnancy. Levels of IgG to VIR antigens were indicative of cumulative malaria exposure and increased with current P. vivax infection and P. falciparum co-infection. Antibody data were consistent with levels of malaria endemicity and current prevalence in the diverse geographical areas studied. In addition, the magnitude of IgG response to two VIR antigens at delivery was associated with higher birth weight. Furthermore, T cell responses to VIR antigens were naturally induced and their magnitude varied according to P. vivax infectious status. Peripheral blood mononuclear cells from uninfected pregnant women from a highly endemic area produced higher TH1 (IFN-γ) and lower pro-inflammatory cytokines (TNF and IL-6) upon stimulation with a long synthetic peptide representing conserved globular domains of VIR antigens than P. vivax-infected women. Data suggest that further investigation on these antigens as potential targets of immunity in naturally-exposed individuals is warranted.
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Affiliation(s)
- Pilar Requena
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Edmilson Rui
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Norma Padilla
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Flor E. Martínez-Espinosa
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil
- Instituto Leônidas e Maria Deane (ILMD/Fiocruz Amazonia), Brazil
| | | | - Camila Bôtto-Menezes
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil
- Universidade do Estado do Amazonas, Manaus, Amazonas, Brazil
| | - Adriana Malheiro
- Instituto de Ciências Biológicas. Universidade Federal do Amazonas, Manaus, Brazil
| | | | - Swati Kochar
- Department of Medicine, Medical College, Bikaner, Rajasthan, India
| | - Sanjay K. Kochar
- Department of Medicine, Medical College, Bikaner, Rajasthan, India
| | | | | | - Maria Ome-Kaius
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Regina Wangnapi
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Dhiraj Hans
- International Center for Genetic Engineering and Biotechnology, Delhi, India
| | - Michela Menegon
- Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca Mateo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Sergi Sanz
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Meghna Desai
- Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Malaria Branch, Atlanta, Georgia, United States of America
| | - Alfredo Mayor
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Chetan C. Chitnis
- International Center for Genetic Engineering and Biotechnology, Delhi, India
| | - Azucena Bardají
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Ivo Mueller
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Walter and Eliza Hall Institute, Parkville, Australia
| | - Stephen Rogerson
- Department of Medicine, University of Melbourne, Melbourne, Australia
| | - Carlo Severini
- Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Carmen Fernández-Becerra
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Clara Menéndez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Hernando del Portillo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- ICREA, Barcelona, Spain
- * E-mail: (HdP); (CD)
| | - Carlota Dobaño
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- * E-mail: (HdP); (CD)
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Sheikh IH, Kaushal DC, Chandra D, Kaushal NA. Immunogenicity of a plasmid DNA vaccine encoding 42kDa fragment of Plasmodium vivax merozoite surface protein-1. Acta Trop 2016; 162:66-74. [PMID: 27311385 DOI: 10.1016/j.actatropica.2016.06.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 06/07/2016] [Accepted: 06/10/2016] [Indexed: 11/17/2022]
Abstract
Plasmodium vivax is the second major human malaria parasite that inflicts debilitating morbidity and consequent economic impact in South-East Asian countries. The relapsing nature of P. vivax along with the emergence of drug-resistant P. vivax strains has emphasized the urgent need for a vaccine. However, the development of an effective vivax vaccine is seriously hampered due to the diversity and variation in parasite antigens and non-availability of suitable animal models. DNA based vaccines represent an alternative approach in inducing immunity to multiple targets from different stages of malaria parasite. DNA prime-boosting strategies induce both antibody mediated and cell-mediated immune responses that are the major mechanisms of protection against malaria parasites. We have earlier studied the immunogenicity and protective efficacy of the soluble and refolded forms of recombinant 42kDa fragment of Plasmodium vivax merozoite surface protein-1 (PvMSP-142) using P. cynomolgi rhesus monkey model. In the present study, we have constructed a recombinant DNA vaccine encoding 42kDa fragment of P. vivax MSP-1 and studied the immunogenicity of PvMSP-142 DNA vaccine construct in mice. The 42kDa gene fragment of PvMSP-1 was PCR amplified using gene specific primers and subcloned into pcDNA 3.1 (+) eukaryotic expression vector. In vitro expression of PvMSP-142 plasmid construct was checked by transfection in COS-1 cell line. Indirect immunofluorescence of transfected COS-1 cells probed with monoclonal antibodies against PvMSP-142 exhibited positive fluorescence. Immunization of BALB/c mice with PvMSP-142-pcDNA vaccine construct revealed the immunogenicity of recombinant vaccine plasmid that can be enhanced by prime boosting with recombinant protein corresponding to the DNA vaccine as evidenced by significant elevation of antibody and the cytokines responses.
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Affiliation(s)
- Inayat Hussain Sheikh
- Division of Parasitology, CSIR- Central Drug Research Institute, Lucknow 226031, India; Department of Biochemistry, Lucknow University, Lucknow, India.
| | - Deep C Kaushal
- Amity University Uttar Pradesh, Lucknow Campus, Lucknow 226028, India.
| | - Deepak Chandra
- Department of Biochemistry, Lucknow University, Lucknow, India.
| | - Nuzhat A Kaushal
- Division of Parasitology, CSIR- Central Drug Research Institute, Lucknow 226031, India.
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Reduced Parasite Burden in Children with Falciparum Malaria and Bacteremia Coinfections: Role of Mediators of Inflammation. Mediators Inflamm 2016; 2016:4286576. [PMID: 27418744 PMCID: PMC4933845 DOI: 10.1155/2016/4286576] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/28/2016] [Indexed: 01/07/2023] Open
Abstract
Bacteremia and malaria coinfection is a common and life-threatening condition in children residing in sub-Saharan Africa. We previously showed that coinfection with Gram negative (G[-]) enteric Bacilli and Plasmodium falciparum (Pf[+]) was associated with reduced high-density parasitemia (HDP, >10,000 parasites/μL), enhanced respiratory distress, and severe anemia. Since inflammatory mediators are largely unexplored in such coinfections, circulating cytokines were determined in four groups of children (n = 206, aged <3 yrs): healthy; Pf[+] alone; G[-] coinfected; and G[+] coinfected. Staphylococcus aureus and non-Typhi Salmonella were the most frequently isolated G[+] and G[-] organisms, respectively. Coinfected children, particularly those with G[-] pathogens, had lower parasite burden (peripheral and geometric mean parasitemia and HDP). In addition, both coinfected groups had increased IL-4, IL-5, IL-7, IL-12, IL-15, IL-17, IFN-γ, and IFN-α and decreased TNF-α relative to malaria alone. Children with G[-] coinfection had higher IL-1β and IL-1Ra and lower IL-10 than the Pf[+] group and higher IFN-γ than the G[+] group. To determine how the immune response to malaria regulates parasitemia, cytokine production was investigated with a multiple mediation model. Cytokines with the greatest mediational impact on parasitemia were IL-4, IL-10, IL-12, and IFN-γ. Results here suggest that enhanced immune activation, especially in G[-] coinfected children, acts to reduce malaria parasite burden.
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63
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Ishizuka AS, Lyke KE, DeZure A, Berry AA, Richie TL, Mendoza FH, Enama ME, Gordon IJ, Chang LJ, Sarwar UN, Zephir KL, Holman LA, James ER, Billingsley PF, Gunasekera A, Chakravarty S, Manoj A, Li M, Ruben AJ, Li T, Eappen AG, Stafford RE, K C N, Murshedkar T, DeCederfelt H, Plummer SH, Hendel CS, Novik L, Costner PJM, Saunders JG, Laurens MB, Plowe CV, Flynn B, Whalen WR, Todd JP, Noor J, Rao S, Sierra-Davidson K, Lynn GM, Epstein JE, Kemp MA, Fahle GA, Mikolajczak SA, Fishbaugher M, Sack BK, Kappe SHI, Davidson SA, Garver LS, Björkström NK, Nason MC, Graham BS, Roederer M, Sim BKL, Hoffman SL, Ledgerwood JE, Seder RA. Protection against malaria at 1 year and immune correlates following PfSPZ vaccination. Nat Med 2016; 22:614-23. [PMID: 27158907 DOI: 10.1038/nm.4110] [Citation(s) in RCA: 254] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/15/2016] [Indexed: 02/07/2023]
Abstract
An attenuated Plasmodium falciparum (Pf) sporozoite (SPZ) vaccine, PfSPZ Vaccine, is highly protective against controlled human malaria infection (CHMI) 3 weeks after immunization, but the durability of protection is unknown. We assessed how vaccine dosage, regimen, and route of administration affected durable protection in malaria-naive adults. After four intravenous immunizations with 2.7 × 10(5) PfSPZ, 6/11 (55%) vaccinated subjects remained without parasitemia following CHMI 21 weeks after immunization. Five non-parasitemic subjects from this dosage group underwent repeat CHMI at 59 weeks, and none developed parasitemia. Although Pf-specific serum antibody levels correlated with protection up to 21-25 weeks after immunization, antibody levels waned substantially by 59 weeks. Pf-specific T cell responses also declined in blood by 59 weeks. To determine whether T cell responses in blood reflected responses in liver, we vaccinated nonhuman primates with PfSPZ Vaccine. Pf-specific interferon-γ-producing CD8 T cells were present at ∼100-fold higher frequencies in liver than in blood. Our findings suggest that PfSPZ Vaccine conferred durable protection to malaria through long-lived tissue-resident T cells and that administration of higher doses may further enhance protection.
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Affiliation(s)
- Andrew S Ishizuka
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Kirsten E Lyke
- Institute for Global Health, Center for Vaccine Development and Division of Malaria Research, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Adam DeZure
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Andrea A Berry
- Institute for Global Health, Center for Vaccine Development and Division of Malaria Research, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Floreliz H Mendoza
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Mary E Enama
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Ingelise J Gordon
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Lee-Jah Chang
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Uzma N Sarwar
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Kathryn L Zephir
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - LaSonji A Holman
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | | | | | | | | | | | - MingLin Li
- Sanaria Inc., Rockville, Maryland, USA
- Protein Potential, LLC, Rockville, Maryland, USA
| | | | - Tao Li
- Sanaria Inc., Rockville, Maryland, USA
| | | | - Richard E Stafford
- Sanaria Inc., Rockville, Maryland, USA
- Protein Potential, LLC, Rockville, Maryland, USA
| | - Natasha K C
- Sanaria Inc., Rockville, Maryland, USA
- Protein Potential, LLC, Rockville, Maryland, USA
| | | | - Hope DeCederfelt
- Pharmaceutical Development Section, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Sarah H Plummer
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Cynthia S Hendel
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Laura Novik
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Pamela J M Costner
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Jamie G Saunders
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Matthew B Laurens
- Institute for Global Health, Center for Vaccine Development and Division of Malaria Research, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Christopher V Plowe
- Institute for Global Health, Center for Vaccine Development and Division of Malaria Research, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Barbara Flynn
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - William R Whalen
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - J P Todd
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Jay Noor
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Srinivas Rao
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Kailan Sierra-Davidson
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Geoffrey M Lynn
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Judith E Epstein
- Naval Medical Research Center (NMRC), Malaria Department, Silver Spring, Maryland, USA
| | - Margaret A Kemp
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Gary A Fahle
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | | | | | - Brandon K Sack
- Center for Infectious Disease Research, Seattle, Washington, USA
| | - Stefan H I Kappe
- Center for Infectious Disease Research, Seattle, Washington, USA
| | - Silas A Davidson
- Entomology Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Lindsey S Garver
- Entomology Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Niklas K Björkström
- Center for Infectious Medicine, Department of Medicine Huddinge, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Martha C Nason
- Biostatistics Research Branch, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Barney S Graham
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Mario Roederer
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - B Kim Lee Sim
- Sanaria Inc., Rockville, Maryland, USA
- Protein Potential, LLC, Rockville, Maryland, USA
| | | | - Julie E Ledgerwood
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
| | - Robert A Seder
- Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda (NIH), Maryland, USA
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Abstract
Naturally acquired immunity to the blood-stage of the malaria parasite develops slowly in areas of high endemicity, but is not sterilizing. It manifests as a reduction in parasite density and clinical symptoms. Immunity as a result of blood-stage vaccination has not yet been achieved in humans, although there are many animal models where vaccination has been successful. The development of a blood-stage vaccine has been complicated by a number of factors including limited knowledge of human-parasite interactions and which antigens and immune responses are critical for protection. Opinion is divided as to whether this vaccine should aim to accelerate the acquisition of responses acquired following natural exposure, or whether it should induce a different response. Animal and experimental human models suggest that cell-mediated immune responses can control parasite growth, but these responses can also contribute to significant immunopathology if unregulated. They are largely ignored in most blood-stage malaria vaccine development strategies. Here, we discuss key observations relating to cell-mediated immune responses in the context of experimental human systems and field studies involving naturally exposed individuals and how this may inform the development of a blood-stage malaria vaccine.
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65
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Farrington LA, Jagannathan P, McIntyre TI, Vance HM, Bowen K, Boyle MJ, Nankya F, Wamala S, Auma A, Nalubega M, Sikyomu E, Naluwu K, Bigira V, Kapisi J, Dorsey G, Kamya MR, Feeney ME. Frequent Malaria Drives Progressive Vδ2 T-Cell Loss, Dysfunction, and CD16 Up-regulation During Early Childhood. J Infect Dis 2015; 213:1483-90. [PMID: 26667315 DOI: 10.1093/infdis/jiv600] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 12/04/2015] [Indexed: 12/13/2022] Open
Abstract
γδ T cells expressing Vδ2 may be instrumental in the control of malaria, because they inhibit the replication of blood-stage parasites in vitro and expand during acute malaria infection. However, Vδ2 T-cell frequencies and function are lower among children with heavy prior malaria exposure. It remains unclear whether malaria itself is driving this loss. Here we measure Vδ2 T-cell frequency, cytokine production, and degranulation longitudinally in Ugandan children enrolled in a malaria chemoprevention trial from 6 to 36 months of age. We observed a progressive attenuation of the Vδ2 response only among children incurring high rates of malaria. Unresponsive Vδ2 T cells were marked by expression of CD16, which was elevated in the setting of high malaria transmission. Moreover, chemoprevention during early childhood prevented the development of dysfunctional Vδ2 T cells. These observations provide insight into the role of Vδ2 T cells in the immune response to chronic malaria.
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Affiliation(s)
| | | | - Tara I McIntyre
- Departments of Medicine, University of California San Francisco
| | - Hilary M Vance
- Departments of Medicine, University of California San Francisco
| | - Katherine Bowen
- Departments of Medicine, University of California San Francisco
| | - Michelle J Boyle
- Departments of Medicine, University of California San Francisco Center for Biomedical Research, The Burnet Institute, Melbourne, Victoria, Australia
| | - Felistas Nankya
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Samuel Wamala
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Ann Auma
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Mayimuna Nalubega
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Esther Sikyomu
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Kate Naluwu
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Victor Bigira
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - James Kapisi
- Infectious Diseases Research Collaboration, Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- Departments of Medicine, University of California San Francisco
| | - Moses R Kamya
- Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Margaret E Feeney
- Departments of Medicine, University of California San Francisco Pediatrics, University of California San Francisco
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66
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Affiliation(s)
- Thayer King
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Tracey Lamb
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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67
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Matar CG, Jacobs NT, Speck SH, Lamb TJ, Moormann AM. Does EBV alter the pathogenesis of malaria? Parasite Immunol 2015; 37:433-45. [DOI: 10.1111/pim.12212] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 05/20/2015] [Indexed: 02/06/2023]
Affiliation(s)
- C. G. Matar
- Department of Microbiology and Immunology; Emory University School of Medicine; Atlanta GA USA
| | - N. T. Jacobs
- Department of Pediatrics; Emory University School of Medicine; Atlanta GA USA
| | - S. H. Speck
- Department of Microbiology and Immunology; Emory University School of Medicine; Atlanta GA USA
- Emory Vaccine Center; Emory University; Atlanta GA USA
| | - T. J. Lamb
- Department of Pediatrics; Emory University School of Medicine; Atlanta GA USA
| | - A. M. Moormann
- Program in Molecular Medicine; University of Massachusetts Medical School; Worcester MA USA
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68
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Eriksson EM, Schofield L. Dysfunctional γδ T cells: a contributing factor for clinical tolerance to malaria? ANNALS OF TRANSLATIONAL MEDICINE 2015; 3:S34. [PMID: 26046081 DOI: 10.3978/j.issn.2305-5839.2015.03.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 02/18/2015] [Indexed: 11/14/2022]
Affiliation(s)
- Emily M Eriksson
- 1 Walter and Eliza Hall Institute of Medical Science and University of Melbourne, Department of Medical Biology, VIC 3052, Australia ; 2 Australian Institute of Tropical Health and Medicine, James Cook University, Queensland 4811, Australia
| | - Louis Schofield
- 1 Walter and Eliza Hall Institute of Medical Science and University of Melbourne, Department of Medical Biology, VIC 3052, Australia ; 2 Australian Institute of Tropical Health and Medicine, James Cook University, Queensland 4811, Australia
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69
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Jagannathan P, Kim CC, Greenhouse B, Nankya F, Bowen K, Eccles-James I, Muhindo MK, Arinaitwe E, Tappero JW, Kamya MR, Dorsey G, Feeney ME. Loss and dysfunction of Vδ2⁺ γδ T cells are associated with clinical tolerance to malaria. Sci Transl Med 2015; 6:251ra117. [PMID: 25163477 DOI: 10.1126/scitranslmed.3009793] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Although clinical immunity to malaria eventually develops among children living in endemic settings, the underlying immunologic mechanisms are not known. The Vδ2(+) subset of γδ T cells have intrinsic reactivity to malaria antigens, can mediate killing of Plasmodium falciparum merozoites, and expand markedly in vivo after malaria infection in previously naïve hosts, but their role in mediating immunity in children repeatedly exposed to malaria is unclear. We evaluated γδ T cell responses to malaria among 4-year-old children enrolled in a longitudinal study in Uganda. We found that repeated malaria was associated with reduced percentages of Vδ2(+) γδ T cells in peripheral blood, decreased proliferation and cytokine production in response to malaria antigens, and increased expression of immunoregulatory genes. Further, loss and dysfunction of proinflammatory Vδ2(+) γδ T cells were associated with a reduced likelihood of symptoms upon subsequent P. falciparum infection. Together, these results suggest that repeated malaria infection during childhood results in progressive loss and dysfunction of Vδ2(+) γδ T cells that may facilitate immunological tolerance of the parasite.
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Affiliation(s)
- Prasanna Jagannathan
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Charlie C Kim
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Bryan Greenhouse
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Felistas Nankya
- Infectious Diseases Research Collaboration, P.O. Box 7475, Kampala, Uganda
| | - Katherine Bowen
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Ijeoma Eccles-James
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Mary K Muhindo
- Infectious Diseases Research Collaboration, P.O. Box 7475, Kampala, Uganda
| | - Emmanuel Arinaitwe
- Infectious Diseases Research Collaboration, P.O. Box 7475, Kampala, Uganda
| | - Jordan W Tappero
- Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Moses R Kamya
- Department of Medicine, Makerere University College of Health Sciences, P.O. Box 7051, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Margaret E Feeney
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA. Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA.
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70
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Mahanta A, Kar SK, Kakati S, Baruah S. Heightened inflammation in severe malaria is associated with decreased IL-10 expression levels and neutrophils. Innate Immun 2014; 21:546-52. [PMID: 25466232 DOI: 10.1177/1753425914561277] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 09/26/2014] [Indexed: 12/31/2022] Open
Abstract
Dysregulation of the cytokine network in severe malaria owing to variations in factors like parasite load, strains and host factors is well documented but the key cytokines that are dysregulated remain poorly elucidated. Longitudinal changes in cytokine levels in an individual with parasitemia and disease resolution is likely to identify the key cytokines. We have analyzed the mRNA expression of cytokines over a 7-d period in severe (SM) and uncomplicated (UM) Plasmodium falciparum malaria. We found up-regulated expression of TNF-α, IL-1β, IFN-γ and TGF-β in SM, with decreased expression of IL-10 on d 0. Further, we observed a negative correlation of IL-10 expression with parasitemia and pro-inflammatory cytokines, suggesting IL-10 to be the key cytokine in tilting the balance to an inflammatory response. Longitudinal analysis revealed that the key cytokines associated with disease were TNF-α, IL-1β, IFN-γ, IL-12α, RANTES and TGF-β, while TNF-α, IL-10 and TGF-β discriminated between SM and UM. A higher neutrophil count in SM and its positive association with parasite density and IL-1β and IL-8 provides support for neutrophils in inflammation in malaria. Our findings suggest subversion of anti-inflammatory response in SM by parasite factors towards an exaggerated pro-inflammatory response with involvement of neutrophils, the classical inflammatory cells.
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Affiliation(s)
- Anusree Mahanta
- Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Tezpur, Assam, India
| | - Santosh K Kar
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Sanjeeb Kakati
- Department of Medicine, Assam Medical College & Hospital, Dibrugarh, Assam, India
| | - Shashi Baruah
- Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Tezpur, Assam, India
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71
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Moncunill G, Han H, Dobaño C, McElrath MJ, De Rosa SC. OMIP-024: pan-leukocyte immunophenotypic characterization of PBMC subsets in human samples. Cytometry A 2014; 85:995-8. [PMID: 25352070 DOI: 10.1002/cyto.a.22580] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 10/06/2014] [Indexed: 01/22/2023]
Affiliation(s)
- Gemma Moncunill
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, 98109; Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Catalonia, Spain
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72
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Gun SY, Claser C, Tan KSW, Rénia L. Interferons and interferon regulatory factors in malaria. Mediators Inflamm 2014; 2014:243713. [PMID: 25157202 PMCID: PMC4124246 DOI: 10.1155/2014/243713] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 06/18/2014] [Indexed: 12/29/2022] Open
Abstract
Malaria is one of the most serious infectious diseases in humans and responsible for approximately 500 million clinical cases and 500 thousand deaths annually. Acquired adaptive immune responses control parasite replication and infection-induced pathologies. Most infections are clinically silent which reflects on the ability of adaptive immune mechanisms to prevent the disease. However, a minority of these can become severe and life-threatening, manifesting a range of overlapping syndromes of complex origins which could be induced by uncontrolled immune responses. Major players of the innate and adaptive responses are interferons. Here, we review their roles and the signaling pathways involved in their production and protection against infection and induced immunopathologies.
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Affiliation(s)
- Sin Yee Gun
- Singapore Immunology Network, Agency for Science, Technology and Research (ASTAR), Singapore 138648
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Carla Claser
- Singapore Immunology Network, Agency for Science, Technology and Research (ASTAR), Singapore 138648
| | - Kevin Shyong Wei Tan
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Laurent Rénia
- Singapore Immunology Network, Agency for Science, Technology and Research (ASTAR), Singapore 138648
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
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73
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Changes in antigen-specific cytokine and chemokine responses to Plasmodium falciparum antigens in a highland area of Kenya after a prolonged absence of malaria exposure. Infect Immun 2014; 82:3775-82. [PMID: 24958707 DOI: 10.1128/iai.01924-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Individuals naturally exposed to Plasmodium falciparum lose clinical immunity after a prolonged lack of exposure. P. falciparum antigen-specific cytokine responses have been associated with protection from clinical malaria, but the longevity of P. falciparum antigen-specific cytokine responses in the absence of exposure is not well characterized. A highland area of Kenya with low and unstable malaria transmission provided an opportunity to study this question. The levels of antigen-specific cytokines and chemokines associated in previous studies with protection from clinical malaria (gamma interferon [IFN-γ], interleukin-10 [IL-10], and tumor necrosis factor alpha [TNF-α]), with increased risk of clinical malaria (IL-6), or with pathogenesis of severe disease in malaria (IL-5 and RANTES) were assessed by cytometric bead assay in April 2008, October 2008, and April 2009 in 100 children and adults. During the 1-year study period, none had an episode of clinical P. falciparum malaria. Two patterns of cytokine responses emerged, with some variation by antigen: a decrease at 6 months (IFN-γ and IL-5) or at both 6 and 12 months (IL-10 and TNF-α) or no change over time (IL-6 and RANTES). These findings document that P. falciparum antigen-specific cytokine responses associated in prior studies with protection from malaria (IFN-γ, TNF-α, and IL-10) decrease significantly in the absence of P. falciparum exposure, whereas those associated with increased risk of malaria (IL-6) do not. The study findings provide a strong rationale for future studies of antigen-specific IFN-γ, TNF-α, and IL-10 responses as biomarkers of increased population-level susceptibility to malaria after prolonged lack of P. falciparum exposure.
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74
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Deroost K, Opdenakker G, Van den Steen PE. MalarImDB: an open-access literature-based malaria immunology database. Trends Parasitol 2014; 30:309-16. [DOI: 10.1016/j.pt.2014.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/28/2014] [Accepted: 04/04/2014] [Indexed: 12/23/2022]
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75
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de Souza JB. Protective immunity against malaria after vaccination. Parasite Immunol 2014; 36:131-9. [PMID: 24188045 DOI: 10.1111/pim.12086] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 10/29/2013] [Indexed: 11/28/2022]
Abstract
A good understanding of the immunological correlates of protective immunity is an important requirement for the development of effective vaccines against malaria. However, this concern has received little attention even in the face of two decades of intensive vaccine research. Here, we review the immune response to blood-stage malaria, with a particular focus on the type of vaccine most likely to induce the kind of response required to give strong protection against infection.
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Affiliation(s)
- J B de Souza
- Faculty of Infectious and Tropical Diseases, Department of Immunity and Infection, London School of Hygiene & Tropical Medicine, London, UK; Division of Infection & Immunity, University College London Medical School, London, UK
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76
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Gonçalves RM, Lima NF, Ferreira MU. Parasite virulence, co-infections and cytokine balance in malaria. Pathog Glob Health 2014; 108:173-8. [PMID: 24854175 DOI: 10.1179/2047773214y.0000000139] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Strong early inflammatory responses followed by a timely production of regulatory cytokines are required to control malaria parasite multiplication without inducing major host pathology. Here, we briefly examine the homeostasis of inflammatory responses to malaria parasite species with varying virulence levels and discuss how co-infections with bacteria, viruses, and helminths can modulate inflammation, either aggravating or alleviating malaria-related morbidity.
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77
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van den Bogaart E, Talha ABA, Straetemans M, Mens PF, Adams ER, Grobusch MP, Nour BYM, Schallig HDFH. Cytokine profiles amongst Sudanese patients with visceral leishmaniasis and malaria co-infections. BMC Immunol 2014; 15:16. [PMID: 24886212 PMCID: PMC4024313 DOI: 10.1186/1471-2172-15-16] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 04/16/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND The immune system plays a critical role in the development of co-infections, promoting or preventing establishment of multiple infections and shaping the outcome of pathogen-host interactions. Its ability to mediate the interplay between visceral leishmaniasis (VL) and malaria has been suggested, but poorly documented. The present study investigated whether concomitant infection with Leishmania donovani complex and Plasmodium falciparum in naturally co-infected patients altered the immunological response elicited by the two pathogens individually. RESULTS Circulating levels of interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12p70, IL-13, IL-17A and tumor necrosis factor (TNF) were assessed in sera of patients infected with active VL and/or malaria and healthy individuals from Gedarif State, Sudan. Comparative analysis of cytokine profiles from co- and mono-infected patients highlighted significant differences in the immune response mounted upon co-infection, confirming the ability of L. donovani and P. falciparum to mutually interact at the immunological level. Progressive polarization towards type-1 and pro-inflammatory cytokine patterns characterized the co-infected patients, whose response partly reflected the effect elicited by VL (IFN-γ, TNF) and malaria (IL-2, IL-13), and partly resulted from a synergistic interaction of the two diseases upon each other (IL-17A). Significantly reduced levels of P. falciparum parasitaemia (P <0.01) were detected in the co-infected group as opposed to the malaria-only patients, suggesting either a protective or a non-detrimental effect of the co-infection against P. falciparum infection. CONCLUSIONS These findings suggest that a new immunological scenario may occur when L. donovani and P. falciparum co-infect the same patient, with potential implications on the course and resolution of these diseases.
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Affiliation(s)
- Erika van den Bogaart
- Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands.
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78
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Stanisic DI, Cutts J, Eriksson E, Fowkes FJI, Rosanas-Urgell A, Siba P, Laman M, Davis TME, Manning L, Mueller I, Schofield L. γδ T cells and CD14+ monocytes are predominant cellular sources of cytokines and chemokines associated with severe malaria. J Infect Dis 2014; 210:295-305. [PMID: 24523513 DOI: 10.1093/infdis/jiu083] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Severe malaria (SM) is associated with high levels of cytokines such as tumor necrosis factor (TNF), interleukin 1 (IL-1), and interleukin 6 (IL-6). The role of chemokines is less clear, as is their cellular source. METHODS In a case-control study of children with SM (n = 200), uncomplicated malaria (UM) (n = 153) and healthy community controls (HC) (n = 162) in Papua, New Guinea, we measured cytokine/chemokine production by peripheral blood mononuclear cells (PBMCs) stimulated with live Plasmodium falciparum parasitized red blood cells (pRBC). Cellular sources were determined. Associations between immunological endpoints and clinical/parasitological variables were tested. RESULTS Compared to HC and UM, children with SM produced significantly higher IL-10, IP-10, MIP-1βm and MCP-2. TNF and MIP-1α were significantly higher in the SM compared to the UM group. IL-10, IL-6, MIP-1α, MIP-1β, and MCP-2 were associated with increased odds of SM. SM syndromes were associated with distinct cytokine/chemokine response profiles compared to UM cases. TNF, MIP-1β, and MIP-1α were produced predominantly by monocytes and γδ T cells, and IL-10 by CD4(+) T cells. CONCLUSIONS Early/innate PBMC responses to pRBC in vitro are informative as to cytokines/chemokines associated with SM. Predominant cellular sources are monocytes and γδ T cells. Monocyte-derived chemokines support a role for monocyte infiltrates in the etiology of SM.
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Affiliation(s)
- Danielle I Stanisic
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Victoria, Australia Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Julia Cutts
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Emily Eriksson
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Victoria, Australia Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Freya J I Fowkes
- Burnet Institute for Medical Research and Public Health, Prahan, Victoria, Australia
| | | | - Peter Siba
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, Western Australia, Australia
| | - Timothy M E Davis
- School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, Western Australia, Australia
| | - Laurens Manning
- School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, Western Australia, Australia
| | - Ivo Mueller
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Victoria, Australia Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea Center de Recerca en Salut Internacional de Barcelona (CRESIB), Barcelona, Spain
| | - Louis Schofield
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Victoria, Australia Australian Institute of Tropical Health and Medicine, James Cook University, Queensland, Australia
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79
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Ludlow LE, Hasang W, Umbers AJ, Forbes EK, Ome M, Unger HW, Mueller I, Siba PM, Jaworowski A, Rogerson SJ. Peripheral blood mononuclear cells derived from grand multigravidae display a distinct cytokine profile in response to P. falciparum infected erythrocytes. PLoS One 2014; 9:e86160. [PMID: 24465935 PMCID: PMC3899203 DOI: 10.1371/journal.pone.0086160] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 12/06/2013] [Indexed: 12/02/2022] Open
Abstract
Immunopathology of placental malaria is most significant in women in their first pregnancy especially in endemic areas, due to a lack of protective immunity to Plasmodium falciparum, which is acquired in successive pregnancies. In some studies (but not all), grand multigravidae (defined as 5 or more pregnancies, G5–7) are more susceptible to poor birth outcomes associated with malaria compared to earlier gravidities. By comparing peripheral cellular responses in primigravidae (G1), women in their second to fourth pregnancy (G2–4) and grand multigravidae we sought to identify key components of the dysregulated immune response. PBMC were exposed to CS2-infected erythrocytes (IE) opsonised with autologous plasma or unopsonised IE, and cytokine and chemokine secretion was measured. Higher levels of opsonising antibody were present in plasma derived from multigravid compared to primigravid women. Significant differences in the levels of cytokines and chemokines secreted in response to IE were observed. Less IL-10, IL-1β, IL-6 and TNF but more CXCL8, CCL8, IFNγ and CXCL10 were detected in G5–7 compared to G2–4 women. Our study provides fresh insight into the modulation of peripheral blood cell function and effects on the balance between host protection and immunopathology during placental malaria infection.
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Affiliation(s)
- Louise E Ludlow
- Department of Medicine (RMH), University of Melbourne, Post Office Royal Melbourne Hospital, Melbourne, Victoria, Australia ; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, Australia
| | - Wina Hasang
- Department of Medicine (RMH), University of Melbourne, Post Office Royal Melbourne Hospital, Melbourne, Victoria, Australia ; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, Australia
| | - Alexandra J Umbers
- Department of Medicine (RMH), University of Melbourne, Post Office Royal Melbourne Hospital, Melbourne, Victoria, Australia ; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, Australia ; Papua New Guinea Institute of Medical Research, Vector Borne Disease Unit, Madang, PNG
| | - Emily K Forbes
- Department of Medicine (RMH), University of Melbourne, Post Office Royal Melbourne Hospital, Melbourne, Victoria, Australia ; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, Australia
| | - Maria Ome
- Papua New Guinea Institute of Medical Research, Vector Borne Disease Unit, Madang, PNG
| | - Holger W Unger
- Department of Medicine (RMH), University of Melbourne, Post Office Royal Melbourne Hospital, Melbourne, Victoria, Australia ; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, Australia ; Papua New Guinea Institute of Medical Research, Vector Borne Disease Unit, Madang, PNG
| | - Ivo Mueller
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia ; Barcelona Centre for International Health Research (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, Vector Borne Disease Unit, Madang, PNG
| | - Anthony Jaworowski
- Centre for Biomedical Research, Burnet Institute, Melbourne, Victoria, Australia ; Department of Infectious Diseases, Monash University, Victoria, Australia ; Department of Immunology, Monash University, Victoria, Australia
| | - Stephen J Rogerson
- Department of Medicine (RMH), University of Melbourne, Post Office Royal Melbourne Hospital, Melbourne, Victoria, Australia ; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Grattan Street, Parkville, Victoria, Australia
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80
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Jagannathan P, Eccles-James I, Bowen K, Nankya F, Auma A, Wamala S, Ebusu C, Muhindo MK, Arinaitwe E, Briggs J, Greenhouse B, Tappero JW, Kamya MR, Dorsey G, Feeney ME. IFNγ/IL-10 co-producing cells dominate the CD4 response to malaria in highly exposed children. PLoS Pathog 2014; 10:e1003864. [PMID: 24415936 PMCID: PMC3887092 DOI: 10.1371/journal.ppat.1003864] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 11/19/2013] [Indexed: 01/08/2023] Open
Abstract
Although evidence suggests that T cells are critical for immunity to malaria, reliable T cell correlates of exposure to and protection from malaria among children living in endemic areas are lacking. We used multiparameter flow cytometry to perform a detailed functional characterization of malaria-specific T cells in 78 four-year-old children enrolled in a longitudinal cohort study in Tororo, Uganda, a highly malaria-endemic region. More than 1800 episodes of malaria were observed in this cohort, with no cases of severe malaria. We quantified production of IFNγ, TNFα, and IL-10 (alone or in combination) by malaria-specific T cells, and analyzed the relationship of this response to past and future malaria incidence. CD4+ T cell responses were measurable in nearly all children, with the majority of children having CD4+ T cells producing both IFNγ and IL-10 in response to malaria-infected red blood cells. Frequencies of IFNγ/IL10 co-producing CD4+ T cells, which express the Th1 transcription factor T-bet, were significantly higher in children with ≥2 prior episodes/year compared to children with <2 episodes/year (P<0.001) and inversely correlated with duration since malaria (Rho = −0.39, P<0.001). Notably, frequencies of IFNγ/IL10 co-producing cells were not associated with protection from future malaria after controlling for prior malaria incidence. In contrast, children with <2 prior episodes/year were significantly more likely to exhibit antigen-specific production of TNFα without IL-10 (P = 0.003). While TNFα-producing CD4+ T cells were not independently associated with future protection, the absence of cells producing this inflammatory cytokine was associated with the phenotype of asymptomatic infection. Together these data indicate that the functional phenotype of the malaria-specific T cell response is heavily influenced by malaria exposure intensity, with IFNγ/IL10 co-producing CD4+ T cells dominating this response among highly exposed children. These CD4+ T cells may play important modulatory roles in the development of antimalarial immunity. Despite reports of decreasing malaria morbidity across many parts of Africa, the incidence of malaria among children continues to be very high in Uganda, even in the setting of insecticide-treated bednets and artemisinin-based combination therapy. Additional control measures, including a vaccine, are sorely needed in these settings, but progress has been limited by our lack of understanding of immunologic correlates of exposure and protection. T cell responses to malaria are thought to be important for protection in experimental models, but their role in protecting against naturally acquired infection is not clear. In this study, we performed detailed assessments of the malaria-specific T cell response among 4-year-old children living in Tororo, Uganda, an area of high malaria transmission. We found that recent malaria infection induces a malaria-specific immune response dominated by Th1 T cells co-producing IFNγ and IL-10, and that these cells are not associated with protection from future infection. IFNγ/IL-10 co-producing cells have been described in several parasitic infections and are hypothesized to be important in limiting CD4-mediated pathology, but they may also prevent the development of sterilizing immunity. These observations have important implications for understanding the pathophysiology of malaria in humans and for malaria vaccine development.
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Affiliation(s)
- Prasanna Jagannathan
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
| | - Ijeoma Eccles-James
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
| | - Katherine Bowen
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
| | | | - Ann Auma
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Samuel Wamala
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Charles Ebusu
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | - Jessica Briggs
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
| | - Bryan Greenhouse
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
| | - Jordan W. Tappero
- Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Moses R. Kamya
- Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
| | - Margaret E. Feeney
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
- Department of Pediatrics, University of California, San Francisco, San Francisco, California, United States of America
- * E-mail:
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81
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Lourembam SD, Sawian CE, Baruah S. Dysregulation of cytokines expression in complicated falciparum malaria with increased TGF-β and IFN-γ and decreased IL-2 and IL-12. Cytokine 2013; 64:503-8. [PMID: 24012048 DOI: 10.1016/j.cyto.2013.08.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 07/16/2013] [Accepted: 08/13/2013] [Indexed: 11/17/2022]
Abstract
BACKGROUND In Plasmodium falciparum infections, proinflammatory cytokine response is implicated in control of parasite multiplication as well as in disease pathogenesis. However, the regulation of proinflammatory and anti-inflammatory cytokine balance and its relation to disease severity remains poorly understood. METHODS We examined cytokines gene expression by quantitative real time-PCR technique in a case control study comprising of P. falciparum infected (n=58) and non infected (n=30) groups. P. falciparum infected were further stratified as complicated and uncomplicated as per WHO criterion and parasitaemia levels. RESULTS Higher expression of IL-2, IL-12α and TGF-β with decreased levels of IL-10 was seen in P. falciparum positivity. Complicated malaria was associated with enhanced expression of IFN-γ and TGF-β but lower IL-2 and IL-12α in comparison to uncomplicated malaria. Modeling of data suggested higher expression of IL-12α to be predictive of uncomplicated malaria [Odds ratio=3.074, 95% CI (1.254-7.536)] and was negatively associated with complicated malaria outcome (p=0.014). Interestingly, the probability of complicated malaria in males with elevated TNF-α expression was three times higher [p=0.05; Odds ratio=3.412, 95% CI (0.98-11.848)]. Age was also seen to be a factor with higher IL-8 in diseased young (p=0.012). CONCLUSION Our data suggested induction of balanced cytokine response in uncomplicated malaria while cytokine dysregulation with a role for TGF-β was indicated in complicated malaria. TH cells did not appear to be the source of increased IFN-γ expression associated with malaria severity.
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Affiliation(s)
- Sonia D Lourembam
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, Assam, India.
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Megnekou R, Staalsoe T, Hviid L. Cytokine response to pregnancy-associated recrudescence of Plasmodium berghei infection in mice with pre-existing immunity to malaria. Malar J 2013; 12:387. [PMID: 24180253 PMCID: PMC4228397 DOI: 10.1186/1475-2875-12-387] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 10/22/2013] [Indexed: 11/25/2022] Open
Abstract
Background During childhood, residents of areas with stable transmission of Plasmodium falciparum parasites acquire substantial protective immunity to malaria, and adults therefore rarely experience clinical disease episodes. However, susceptibility to infection reappears in pregnant women, particularly primigravidae. This is due to appearance of antigenic parasite variants that are restricted to pregnancy. Variant-specific immunity also governs pregnancy-associated recrudescence of Plasmodium berghei infection in pregnant mice. Pregnancy-related changes in the plasma cytokine levels of mice with immunity acquired prior to first pregnancy have not been studied in detail previously, and were the topic of the present study. Methods A multiplexed bead assay was used to measure plasma levels of IL-5, IL-10, IL-12, IL-13, IFN-γ and TNF in BALB/c mice immunized against P. berghei K173 by repeated infection and drug cure before the first pregnancy. The association between cytokine levels on the one hand and parasitaemia and haemoglobin levels on the other, in mice that had never been pregnant or were pregnant for the first, second or third time were evaluated by Mann–Whitney test and Spearman rank-order correlation analysis. Results Pregnancy per se did not further increase the already high cytokine levels in mice previously immunized by repeated infection and drug cure. Levels of all the cytokines except IL-10 were correlated with each other, and with parasitaemia and haemoglobin levels. Furthermore, levels of all cytokines were positively correlated with parity, except IL-10, which was negatively correlated with parity. High levels of IL-10 and low levels of the other cytokines were associated with poor pregnancy outcome. Conclusions High levels of IL-10 and low levels of the other cytokines were associated with poor pregnancy outcome in this mouse model of placental malaria. Since the model replicates key parasitological and immunological features of placental P. falciparum malaria, it underpins its usefulness in immunology and pathogenesis studies of this important cause of mother/child morbidity in endemic areas.
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Affiliation(s)
| | | | - Lars Hviid
- Centre for Medical Parasitology, Department of Clinical Microbiology and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet) and Institute for International Health, Immunology, and Microbiology, CSS Building 22, Øster Farimagsgade 5, 1014 Copenhagen K, Denmark.
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Hill DL, Eriksson EM, Li Wai Suen CSN, Chiu CY, Ryg-Cornejo V, Robinson LJ, Siba PM, Mueller I, Hansen DS, Schofield L. Opsonising antibodies to P. falciparum merozoites associated with immunity to clinical malaria. PLoS One 2013; 8:e74627. [PMID: 24040299 PMCID: PMC3767630 DOI: 10.1371/journal.pone.0074627] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 08/04/2013] [Indexed: 11/19/2022] Open
Abstract
Naturally acquired humoral immunity to the malarial parasite Plasmodium falciparum can protect against disease, although the precise mechanisms remain unclear. Although antibody levels can be measured by ELISA, few studies have investigated functional antibody assays in relation to clinical outcomes. In this study we applied a recently developed functional assay of antibody-mediated opsonisation of merozoites, to plasma samples from a longitudinal cohort study conducted in a malaria endemic region of Papua New Guinea (PNG). Phagocytic activity was quantified by flow cytometry using a standardized and high-throughput protocol, and was subsequently evaluated for association with protection from clinical malaria and high-density parasitemia. Opsonising antibody responses were found to: i) increase with age, ii) be enhanced by concurrent infection, and iii) correlate with protection from clinical episodes and high-density parasitemia. Stronger protective associations were observed in individuals with no detectable parasitemia at baseline. This study presents the first evidence for merozoite phagocytosis as a correlate of acquired immunity and clinical protection against P. falciparum malaria.
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Affiliation(s)
- Danika L. Hill
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Emily M. Eriksson
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Connie S. N. Li Wai Suen
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Chris Y. Chiu
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Victoria Ryg-Cornejo
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Leanne J. Robinson
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, Goroka, Eastern Highlands Province, Papua, New Guinea
| | - Peter M. Siba
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, Goroka, Eastern Highlands Province, Papua, New Guinea
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
- Barcelona Center for International Health, University of Barcelona, Barcelona, Spain
| | - Diana S. Hansen
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Louis Schofield
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
- * E-mail:
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Inoue SI, Niikura M, Mineo S, Kobayashi F. Roles of IFN-γ and γδ T Cells in Protective Immunity Against Blood-Stage Malaria. Front Immunol 2013; 4:258. [PMID: 24009610 PMCID: PMC3756480 DOI: 10.3389/fimmu.2013.00258] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 08/15/2013] [Indexed: 01/10/2023] Open
Abstract
Malaria is caused by infection with Plasmodium parasites. Various studies with knockout mice have indicated that IFN-γ plays essential roles in protective immunity against blood-stage Plasmodium infection. However, after Plasmodium infection, increased IFN-γ production by various types of cells is involved not only in protective immunity, but also in immunopathology. Recent reports have shown that IFN-γ acts as a pro-inflammatory cytokine to induce not only the activation of macrophages, but also the generation of uncommon myelolymphoid progenitor cells after Plasmodium infection. However, the effects of IFN-γ on hematopoietic stem cells and progenitor cells are unclear. Therefore, the regulation of hematopoiesis by IFN-γ during Plasmodium infection remains to be clarified. Although there are conflicting reports concerning the significance of γδ T cells in protective immunity against Plasmodium infection, γδ T cells may respond to infection and produce IFN-γ as innate immune cells in the early phase of blood-stage malaria. Our recent studies have shown that γδ T cells express CD40 ligand and produce IFN-γ after Plasmodium infection, resulting in the enhancement of dendritic cell activation as part of the immune response to eliminate Plasmodium parasites. These data suggest that the function of γδ T cells is similar to that of NK cells. Although several reports suggest that γδ T cells have the potential to act as memory cells for various infections, it remains to be determined whether memory γδ T cells are generated by Plasmodium infection and whether memory γδ T cells can contribute to the host defense against re-infection with Plasmodium. Here, we summarize and discuss the effects of IFN-γ and the various functions of γδ T cells in blood-stage Plasmodium infection.
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Affiliation(s)
- Shin-Ichi Inoue
- Department of Infectious Diseases, Kyorin University School of Medicine, Mitaka , Tokyo , Japan
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Mueller I, Galinski MR, Tsuboi T, Arevalo-Herrera M, Collins WE, King CL. Natural acquisition of immunity to Plasmodium vivax: epidemiological observations and potential targets. ADVANCES IN PARASITOLOGY 2013; 81:77-131. [PMID: 23384622 DOI: 10.1016/b978-0-12-407826-0.00003-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Population studies show that individuals acquire immunity to Plasmodium vivax more quickly than Plasmodium falciparum irrespective of overall transmission intensity, resulting in the peak burden of P. vivax malaria in younger age groups. Similarly, actively induced P. vivax infections in malaria therapy patients resulted in faster and generally more strain-transcending acquisition of immunity than P. falciparum infections. The mechanisms behind the more rapid acquisition of immunity to P. vivax are poorly understood. Natural acquired immune responses to P. vivax target both pre-erythrocytic and blood-stage antigens and include humoral and cellular components. To date, only a few studies have investigated the association of these immune responses with protection, with most studies focussing on a few merozoite antigens (such as the Pv Duffy binding protein (PvDBP), the Pv reticulocyte binding proteins (PvRBPs), or the Pv merozoite surface proteins (PvMSP1, 3 & 9)) or the circumsporozoite protein (PvCSP). Naturally acquired transmission-blocking (TB) immunity (TBI) was also found in several populations. Although limited, these data support the premise that developing a multi-stage P. vivax vaccine may be feasible and is worth pursuing.
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Affiliation(s)
- Ivo Mueller
- Walter + Eliza Hall Institute, Infection & Immunity Division, Parkville, Victoria, Australia
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Plasmodium coatneyi in rhesus macaques replicates the multisystemic dysfunction of severe malaria in humans. Infect Immun 2013; 81:1889-904. [PMID: 23509137 DOI: 10.1128/iai.00027-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Severe malaria, a leading cause of mortality among children and nonimmune adults, is a multisystemic disorder characterized by complex clinical syndromes that are mechanistically poorly understood. The interplay of various parasite and host factors is critical in the pathophysiology of severe malaria. However, knowledge regarding the pathophysiological mechanisms and pathways leading to the multisystemic disorders of severe malaria in humans is limited. Here, we systematically investigate infections with Plasmodium coatneyi, a simian malaria parasite that closely mimics the biological characteristics of P. falciparum, and develop baseline data and protocols for studying erythrocyte turnover and severe malaria in greater depth. We show that rhesus macaques (Macaca mulatta) experimentally infected with P. coatneyi develop anemia, coagulopathy, and renal and metabolic dysfunction. The clinical course of acute infections required suppressive antimalaria chemotherapy, fluid support, and whole-blood transfusion, mimicking the standard of care for the management of severe malaria cases in humans. Subsequent infections in the same animals progressed with a mild illness in comparison, suggesting that immunity played a role in reducing the severity of the disease. Our results demonstrate that P. coatneyi infection in rhesus macaques can serve as a highly relevant model to investigate the physiological pathways and molecular mechanisms of malaria pathogenesis in naïve and immune individuals. Together with high-throughput postgenomic technologies, such investigations hold promise for the identification of new clinical interventions and adjunctive therapies.
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Zhao J, Deng S, Liang J, Cao Y, Liu J, Du F, Shang H, Cui L, Luo E. Immunogenicity, protective efficacy and safety of a recombinant DNA vaccine encoding truncated Plasmodium yoelii sporozoite asparagine-rich protein 1 (PySAP1). Hum Vaccin Immunother 2013; 9:1104-11. [PMID: 23357857 DOI: 10.4161/hv.23688] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Although great efforts have been undertaken for the development of malaria vaccines, no completely effective malaria vaccines are available yet. Despite being clinically silent, the pre-erythrocytic stage is considered an ideal target for the development of malaria vaccines. Sporozoite asparagine-rich protein 1 (SAP1) is a sporozoite-localized protein that regulates the expression of UIS (upregulated in infectious sporozoites) genes, which are essential for the infectivity of sporozoites. In this study, a recombinant DNA vaccine encoding a predicted antigenic determinant region of Plasmodium yoelii SAP1 (PySAP1) was constructed. Immunization of mice with this DNA vaccine construct resulted in significant elevation of cytokines such as IFN-γ, IL-2, IL-4 and IL-10, and total IgG as compared with control groups immunized with either the empty DNA vector or saline. After challenge with sporozoites, the group receiving the DNA vaccine showed delayed development of parasitemia and prolonged survival time compared with the control group. The DNA vaccine provided partial protection against P. yoelii 17XL infection, with an overall protection rate of 20%. In addition, the DNA vaccine did not show integration into the host genome. Further studies of SAP1 are needed to test whether it can be used as subunit vaccine candidate.
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Affiliation(s)
- Jia Zhao
- Department of Pathogen Biology; College of Basic Medical Sciences; China Medical University; Shenyang, Liaoning P.R. China
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Abstract
OBJECTIVE Malaria and HIV-1 adversely interact, with HIV-positive individuals suffering higher parasite burdens and worse clinical outcomes. However, the mechanisms underlying these disease interactions are unclear. We hypothesized that HIV coinfection impairs the innate immune response to malaria, and that combination antiretroviral therapy (cART) may restore this response. Our aim was to examine the innate inflammatory response of natural killer (NK), natural killer T (NKT), and γδ T-cells isolated from the peripheral blood of HIV-infected therapy-naive donors to malaria parasites, and determine the effect of cART on these responses. METHODS Freshly isolated peripheral blood mononuclear cells from 25 HIV-infected individuals pre-cART (month 0) and post-cART (months 3 and 6), and HIV-negative individuals at matched time-points, were cultured in the presence of Plasmodium falciparum parasitized erythrocytes. Supernatants and cells were collected to assess cytokine production and phenotypic changes. RESULTS Compared to HIV-negative participants, NKT, NK, and γδ T-cell subsets from participants with chronic HIV infection showed marked differences, including decreased production of interferon γ (IFNγ) and tumor necrosis factor (TNF) in response to malaria parasites. IFNγ production was linked to interleukin-18 receptor (IL-18R) expression in all three cell types studied. Six months of cART provided partial cellular reconstitution but had no effect on IL-18R expression, or IFNγ and TNF production. CONCLUSION These data suggest that HIV infection impairs the inflammatory response of innate effector cells to malaria, and that the response is not fully restored within 6 months of cART. This may contribute to higher parasite burdens and ineffective immune responses, and have implications for vaccination initiatives in coinfected individuals.
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Dolo H, Coulibaly YI, Dembele B, Konate S, Coulibaly SY, Doumbia SS, Diallo AA, Soumaoro L, Coulibaly ME, Diakite SAS, Guindo A, Fay MP, Metenou S, Nutman TB, Klion AD. Filariasis attenuates anemia and proinflammatory responses associated with clinical malaria: a matched prospective study in children and young adults. PLoS Negl Trop Dis 2012; 6:e1890. [PMID: 23133692 PMCID: PMC3486872 DOI: 10.1371/journal.pntd.0001890] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 09/17/2012] [Indexed: 11/29/2022] Open
Abstract
Background Wuchereria bancrofti (Wb) and Mansonella perstans (Mp) are blood-borne filarial parasites that are endemic in many countries of Africa, including Mali. The geographic distribution of Wb and Mp overlaps considerably with that of malaria, and coinfection is common. Although chronic filarial infection has been shown to alter immune responses to malaria parasites, its effect on clinical and immunologic responses in acute malaria is unknown. Methodology/Principal Findings To address this question, 31 filaria-positive (FIL+) and 31 filaria-negative (FIL−) children and young adults, matched for age, gender and hemoglobin type, were followed prospectively through a malaria transmission season. Filarial infection was defined by the presence of Wb or Mp microfilariae on calibrated thick smears performed between 10 pm and 2 am and/or by the presence of circulating filarial antigen in serum. Clinical malaria was defined as axillary temperature ≥37.5°C or another symptom or sign compatible with malaria infection plus the presence of asexual malaria parasites on a thick blood smear. Although the incidence of clinical malaria, time to first episode, clinical signs and symptoms, and malaria parasitemia were comparable between the two groups, geometric mean hemoglobin levels were significantly decreased in FIL− subjects at the height of the transmission season compared to FIL+ subjects (11.4 g/dL vs. 12.5 g/dL, p<0.01). Plasma levels of IL-1ra, IP-10 and IL-8 were significantly decreased in FIL+ subjects at the time of presentation with clinical malaria (99, 2145 and 49 pg/ml, respectively as compared to 474, 5522 and 247 pg/ml in FIL− subjects). Conclusions/Significance These data suggest that pre-existent filarial infection attenuates immune responses associated with severe malaria and protects against anemia, but has little effect on susceptibility to or severity of acute malaria infection. The apparent protective effect of filarial infection against anemia is intriguing and warrants further study in a larger cohort. In many regions of the world, including sub-Saharan Africa, concomitant infection with multiple parasites is common. In order to examine the effects of filariasis, a chronic helminth infection, on immune responses and clinical manifestations of acute malaria infection, the authors followed 31 filaria-infected (FIL+) and 31 filaria-uninfected (FIL–) individuals living in a malaria-endemic area of Mali through an entire malaria transmission season for the development of clinical malaria (fever or other symptoms of malaria in the setting of detectable blood parasites). Serum levels of inflammatory cytokines previously associated with severe malaria were decreased in FIL+ subjects at the time of acute clinical malaria. Although there were no differences between FIL+ and FIL– subjects with respect to the time of first episode of malaria or the number or severity of malaria episodes, filarial infection appeared to protect against the development of anemia during the malaria transmission season. These findings demonstrate that chronic filarial infection modulates the immune response to acute malaria. The apparent effect on anemia is intriguing and deserves further study.
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Affiliation(s)
- Housseini Dolo
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Yaya I. Coulibaly
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Benoit Dembele
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Siaka Konate
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Siaka Y. Coulibaly
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Salif S. Doumbia
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Abdallah A. Diallo
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Lamine Soumaoro
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Michel E. Coulibaly
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | | | - Aldiouma Guindo
- Faculty of Medicine, Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Michael P. Fay
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Simon Metenou
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Thomas B. Nutman
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Amy D. Klion
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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Polymorphisms in the Fc gamma receptor IIIA and Toll-like receptor 9 are associated with protection against severe malarial anemia and changes in circulating gamma interferon levels. Infect Immun 2012; 80:4435-43. [PMID: 23045477 DOI: 10.1128/iai.00945-12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
An understanding of the immunogenetic basis of naturally acquired immunity to Plasmodium falciparum infection would aid in the designing of a rationally based malaria vaccine. Variants within the Fc gamma receptors (FcγRs) mediate immunity through engagement of immunoglobulin G and other immune mediators, such as gamma interferon (IFN-γ), resulting in erythrophagocytosis and production of inflammatory cytokines in severe malarial anemia (SMA). The Toll-like receptors (TLRs) trigger transcription of proinflammatory cytokines and induce adaptive immune responses. Therefore, these receptors may condition malaria disease pathogenesis through alteration in adaptive and innate immune responses. To further delineate the impacts of FcγRIIIA and TLR9 in SMA pathogenesis, the associations between FcγRIIIA -176F/V and TLR9 -1237T/C variants, SMA (hemoglobin [Hb] < 6.0 g/dl), and circulating IFN-γ levels were investigated in children (n = 301) from western Kenya with acute malaria. Multivariate logistic regression analysis (controlling for potential confounders) revealed that children with the FcγRIIIA -176V/TLR9 -1237C (VC) variant combination had 64% reduced odds of developing SMA (odds ratio [OR], 0.36; 95% confidence interval [CI], 0.20 to 0.64; P = 0.001), while carriers of the FcγRIIIA -176V/TLR9 -1237T (VT) variant combination were twice as susceptible to SMA (OR, 2.04; 95% CI, 1.19 to 3.50; P = 0.009). Children with SMA had higher circulating IFN-γ levels than non-SMA children (P = 0.008). Hemoglobin levels were negatively correlated with IFN-γ levels (r = -0.207, P = 0.022). Consistently, the FcγRIIIA -176V/TLR9 -1237T (VT) carriers had higher levels of circulating IFN-γ (P = 0.011) relative to noncarriers, supporting the observation that higher IFN-γ levels are associated with SMA. These results demonstrate that FcγRIIIA-176F/V and TLR9 -1237T/C variants condition susceptibility to SMA and functional changes in circulating IFN-γ levels.
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Cytokine balance in human malaria: does Plasmodium vivax elicit more inflammatory responses than Plasmodium falciparum? PLoS One 2012; 7:e44394. [PMID: 22973442 PMCID: PMC3433413 DOI: 10.1371/journal.pone.0044394] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 08/06/2012] [Indexed: 02/08/2023] Open
Abstract
Background The mechanisms by which humans regulate pro- and anti-inflammatory responses on exposure to different malaria parasites remains unclear. Although Plasmodium vivax usually causes a relatively benign disease, this parasite has been suggested to elicit more host inflammation per parasitized red blood cell than P. falciparum. Methodology/Principal Findings We measured plasma concentrations of seven cytokines and two soluble tumor necrosis factor (TNF)-α receptors, and evaluated clinical and laboratory outcomes, in Brazilians with acute uncomplicated infections with P. vivax (n = 85), P. falciparum (n = 30), or both species (n = 12), and in 45 asymptomatic carriers of low-density P. vivax infection. Symptomatic vivax malaria patients, compared to those infected with P. falciparum or both species, had more intense paroxysms, but they had no clear association with a pro-inflammatory imbalance. To the contrary, these patients had higher levels of the regulatory cytokine interleukin (IL)-10, which correlated positively with parasite density, and elevated IL-10/TNF-α, IL-10/interferon (IFN)-γ, IL-10/IL-6 and sTNFRII/TNF-α ratios, compared to falciparum or mixed-species malaria patient groups. Vivax malaria patients had the highest levels of circulating soluble TNF-α receptor sTNFRII. Levels of regulatory cytokines returned to normal values 28 days after P. vivax clearance following chemotherapy. Finally, asymptomatic carriers of low P. vivax parasitemias had substantially lower levels of both inflammatory and regulatory cytokines than did patients with clinical malaria due to either species. Conclusions Controlling fast-multiplying P. falciparum blood stages requires a strong inflammatory response to prevent fulminant infections, while reducing inflammation-related tissue damage with early regulatory cytokine responses may be a more cost-effective strategy in infections with the less virulent P. vivax parasite. The early induction of regulatory cytokines may be a critical mechanism protecting vivax malaria patients from severe clinical complications.
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Ribot JC, deBarros A, Mancio-Silva L, Pamplona A, Silva-Santos B. B7–CD28 Costimulatory Signals Control the Survival and Proliferation of Murine and Human γδ T Cells via IL-2 Production. THE JOURNAL OF IMMUNOLOGY 2012; 189:1202-8. [DOI: 10.4049/jimmunol.1200268] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Omar AH, Yasunami M, Yamazaki A, Shibata H, Ofori MF, Akanmori BD, Shuaibu MN, Kikuchi M, Hirayama K. Toll-like receptor 9 (TLR9) polymorphism associated with symptomatic malaria: a cohort study. Malar J 2012; 11:168. [PMID: 22594374 PMCID: PMC3426469 DOI: 10.1186/1475-2875-11-168] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 04/12/2012] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND In areas mesoendemic for malaria transmission, symptomatic individuals play a significant role as reservoirs for malaria infection. Understanding the pathogenesis of symptomatic malaria is important in devising tools for augmenting malaria control. In this study, the effect of TLR9 polymorphisms on susceptibility to symptomatic malaria was investigated among Ghanaian children. METHODS Four hundred and twenty nine (429) healthy Ghanaian children, aged three to eleven years (3-11 years), were enrolled into a cohort study and actively followed up for symptomatic malaria for one year. Four TLR9 single nucleotide polymorphisms (SNPs) namely: rs187084 (C-1486 T), rs5743836(C-1237 T), rs352139 (G + 1174A) and rs352140 (G + 2848A) were genotyped by direct sequencing, and their attributable and relative risks for symptomatic malaria determined. TLR9 haplotypes were inferred using the PHASE software and analysed for the risk of symptomatic malaria. A luciferase assay was performed to investigate whether the TLR9 haplotypes influence TLR9 promoter activity. RESULTS The rs352139 GG genotype showed a significantly increased relative risk of 4.8 for symptomatic malaria (P = 0.0024) and a higher mean parasitaemia (P = 0.04). Conversely, the rs352140 GG genotype showed a significantly reduced relative risk of 0.34 (P = 0.048). TLR9 haplotypes analyses showed that TTAG haplotype was significantly associated with reduced relative risk of 0.2 for symptomatic malaria (P = 4×10⁻⁶) and a lower mean parasitaemia (0.007), while CTGA haplotype had an increased relative risk of 3.3 (P = 0.005). Functional luciferase reporter gene expression assay revealed that the TTA haplotype had a significantly higher promoter activity than the CCG, CTG and TCG haplotypes. CONCLUSIONS Taken together, these findings indicate a significant association of TLR9 gene polymorphisms with symptomatic malaria among Ghanaian children in Dangme-West district.
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Affiliation(s)
- Ahmeddin H Omar
- Department of Immunogenetics, Institute of Tropical Medicine-NEKKEN and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
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94
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Teirlinck AC, McCall MBB, Roestenberg M, Scholzen A, Woestenenk R, de Mast Q, van der Ven AJAM, Hermsen CC, Luty AJF, Sauerwein RW. Longevity and composition of cellular immune responses following experimental Plasmodium falciparum malaria infection in humans. PLoS Pathog 2011; 7:e1002389. [PMID: 22144890 PMCID: PMC3228790 DOI: 10.1371/journal.ppat.1002389] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 10/05/2011] [Indexed: 01/09/2023] Open
Abstract
Cellular responses to Plasmodium falciparum parasites, in particular interferon-gamma (IFNγ) production, play an important role in anti-malarial immunity. However, clinical immunity to malaria develops slowly amongst naturally exposed populations, the dynamics of cellular responses in relation to exposure are difficult to study and data about the persistence of such responses are controversial. Here we assess the longevity and composition of cellular immune responses following experimental malaria infection in human volunteers. We conducted a longitudinal study of cellular immunological responses to sporozoites (PfSpz) and asexual blood-stage (PfRBC) malaria parasites in naïve human volunteers undergoing single (n = 5) or multiple (n = 10) experimental P. falciparum infections under highly controlled conditions. IFNγ and interleukin-2 (IL-2) responses following in vitro re-stimulation were measured by flow-cytometry prior to, during and more than one year post infection. We show that cellular responses to both PfSpz and PfRBC are induced and remain almost undiminished up to 14 months after even a single malaria episode. Remarkably, not only ‘adaptive’ but also ‘innate’ lymphocyte subsets contribute to the increased IFNγ response, including αβT cells, γδT cells and NK cells. Furthermore, results from depletion and autologous recombination experiments of lymphocyte subsets suggest that immunological memory for PfRBC is carried within both the αβT cells and γδT compartments. Indeed, the majority of cytokine producing T lymphocytes express an CD45RO+ CD62L- effector memory (EM) phenotype both early and late post infection. Finally, we demonstrate that malaria infection induces and maintains polyfunctional (IFNγ+IL-2+) EM responses against both PfRBC and PfSpz, previously found to be associated with protection. These data demonstrate that cellular responses can be readily induced and are long-lived following infection with P. falciparum, with a persisting contribution by not only adaptive but also (semi-)innate lymphocyte subsets. The implications hereof are positive for malaria vaccine development, but focus attention on those factors potentially inhibiting such responses in the field. A decade into the 21st century, malaria remains responsible for an intolerable global health burden and an effective vaccine is sorely needed. Compounding the many technical hurdles in developing such a vaccine, (naturally-acquired) immunity to malaria is generally perceived to be short-lived, although direct evidence from field studies is conflicting. To overcome this issue, we measured the development of immune responses against the malaria parasite Plasmodium falciparum in human volunteers undergoing experimental malaria infections for the first time, allowing a uniquely detailed analysis thereof. We found that cellular immune responses against two clinically-relevant life-stages of the parasite are not only rapidly acquired following even a single malaria infection, but also remain virtually undiminished over a year later – an unprecedented measurement. These findings refute conclusively the notion that an intrinsic defect exists in either the development or persistence of cellular immune responses against malaria. This realization, in conjunction with a growing recognition that such responses are indeed associated with clinical protection against malaria, markedly enhances the prospect of one day developing a successful vaccine. Simultaneously, however, these results re-focus attention on the question of why the development of long-lived immune responses is often inhibited under conditions of natural exposure.
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Affiliation(s)
- Anne C. Teirlinck
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Matthew B. B. McCall
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Meta Roestenberg
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Anja Scholzen
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Rob Woestenenk
- Department of Laboratory Medicine, Laboratory of Hematology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Quirijn de Mast
- Department of General Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Andre J. A. M. van der Ven
- Department of General Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Cornelus C. Hermsen
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Adrian J. F. Luty
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Robert W. Sauerwein
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
- * E-mail:
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95
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Perkins DJ, Were T, Davenport GC, Kempaiah P, Hittner JB, Ong'echa JM. Severe malarial anemia: innate immunity and pathogenesis. Int J Biol Sci 2011; 7:1427-42. [PMID: 22110393 PMCID: PMC3221949 DOI: 10.7150/ijbs.7.1427] [Citation(s) in RCA: 191] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2011] [Indexed: 11/05/2022] Open
Abstract
Greater than 80% of malaria-related mortality occurs in sub-Saharan Africa due to infections with Plasmodium falciparum. The majority of P. falciparum-related mortality occurs in immune-naïve infants and young children, accounting for 18% of all deaths before five years of age. Clinical manifestations of severe falciparum malaria vary according to transmission intensity and typically present as one or more life-threatening complications, including: hyperparasitemia; hypoglycemia; cerebral malaria; severe malarial anemia (SMA); and respiratory distress. In holoendemic transmission areas, SMA is the primary clinical manifestation of severe childhood malaria, with cerebral malaria occurring only in rare cases. Mortality rates from SMA can exceed 30% in pediatric populations residing in holoendemic transmission areas. Since the vast majority of the morbidity and mortality occurs in immune-naïve African children less than five years of age, with SMA as the primary manifestation of severe disease, this review will focus primarily on the innate immune mechanisms that govern malaria pathogenesis in this group of individuals. The pathophysiological processes that contribute to SMA involve direct and indirect destruction of parasitized and non-parasitized red blood cells (RBCs), inefficient and/or suppression of erythropoiesis, and dyserythropoiesis. While all of these causal etiologies may contribute to reduced hemoglobin (Hb) concentrations in malaria-infected individuals, data from our laboratory and others suggest that SMA in immune-naïve children is characterized by a reduced erythropoietic response. One important cause of impaired erythroid responses in children with SMA is dysregulation in the innate immune response. Phagocytosis of malarial pigment hemozoin (Hz) by monocytes, macrophages, and neutrophils is a central factor for promoting dysregulation in innate inflammatory mediators. As such, the role of P. falciparum-derived Hz (PfHz) in mediating suppression of erythropoiesis through its ability to cause dysregulation in pro- and anti-inflammatory cytokines, growth factors, chemokines, and effector molecules is discussed in detail. An improved understanding of the etiological basis of suppression of erythropoietic responses in children with SMA may offer the much needed therapeutic alternatives for control of this global disease burden.
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Affiliation(s)
- Douglas J Perkins
- Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque NM, USA.
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96
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Abstract
A linkage between presence of Sickle Haemoglobin (HbS) and protection from malaria infection and clinical manifestations in certain areas was suspected from early observations and progressively elucidated by more recent studies. Research has confirmed the abovementioned connection, but also clarified how such protection may be abolished by coexistence of sickle cell trait (HbS trait) and alpha thalassemia, which may explain the relatively low incidence of HbS trait in the Mediterranean. The mechanisms of such protective effect are now being investigated: factors of genetic, molecular and immunological nature are prominent. As for genetic factors attention is given to the role of the red blood cell (RBC) membrane complement regulatory proteins as polymorphisms of these components seem to be associated with resistance to severe malaria; genetic ligands like the Duffy group blood antigen, necessary for erythrocytic invasion, and human protein CD36, a major receptor for P. falciparum-infected RBC's, are also under scrutiny: attention is focused also on plasmodium erythrocyte-binding antigens, which bind to RBC surface components. Genome-wide linkage and association studies are now carried out too, in order to identify genes associated with malaria resistance. Only a minor role is attributed to intravascular sickling, phagocytosis and haemolysis, while specific molecular mechanisms are the object of intensive research: among these a decisive role is played by a biochemical sequence, involving activation of haeme oxygenase (HMO-1), whose effect appears mediated by carbon monoxide (CO). A central role in protection from malaria is also played by immunological factors, which may stimulate antibody production to plasmodium antigens in the early years of life; the role of agents like pathogenic CD8 T-cells has been suggested while the effects of molecular actions on the immunity mechanism are presently investigated. It thus appears that protection from malaria can be explained by interaction of different factors: the elucidation of such mechanisms may prove valuable for the prevention and treatment strategy of a disease which still affects large parts of the world.
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Affiliation(s)
- Sandro Eridani
- Department of Biomedical Science and Technology, University of Milan, Milan, Italy
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97
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Ouma C, Davenport GC, Garcia S, Kempaiah P, Chaudhary A, Were T, Anyona SB, Raballah E, Konah SN, Hittner JB, Vulule JM, Ong'echa JM, Perkins DJ. Functional haplotypes of Fc gamma (Fcγ) receptor (FcγRIIA and FcγRIIIB) predict risk to repeated episodes of severe malarial anemia and mortality in Kenyan children. Hum Genet 2011; 131:289-99. [PMID: 21818580 DOI: 10.1007/s00439-011-1076-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 07/19/2011] [Indexed: 12/29/2022]
Abstract
Development of protective immunity against Plasmodium falciparum is partially mediated through binding of malaria-specific IgG to Fc gamma (γ) receptors. Variations in human FcγRIIA-H/R-131 and FcγRIIIB-NA1/NA2 affect differential binding of IgG sub-classes. Since variability in FcγR may play an important role in severe malarial anemia (SMA) pathogenesis by mediating phagocytosis of red blood cells and triggering cytokine production, the relationship between FcγRIIA-H/R131 and FcγRIIIB-NA1/NA2 haplotypes and susceptibility to SMA (Hb < 6.0 g/dL) was investigated in Kenyan children (n = 528) with acute malaria residing in a holoendemic P. falciparum transmission region. In addition, the association between carriage of the haplotypes and repeated episodes of SMA and all-cause mortality were investigated over a 3-year follow-up period. Since variability in FcγR can alter interferon (IFN)-γ production, a mediator of innate and adaptive immune responses, functional associations between the haplotypes and IFN-γ were also explored. During acute malaria, children with SMA had elevated peripheral IFN-γ levels (P = 0.006). Although multivariate logistic regression analyses (controlling for covariates) revealed no associations between the FcγR haplotypes and susceptibility to SMA during acute infection, the FcγRIIA-131H/FcγRIIIB-NA1 haplotype was associated with decreased peripheral IFN-γ (P = 0.046). Longitudinal analyses showed that carriage of the FcγRIIA-131H/FcγRIIIB-NA1 haplotype was associated with reduced risk of SMA (RR 0.65, 95% CI 0.46-0.90; P = 0.012) and all-cause mortality (P = 0.002). In contrast, carriers of the FcγRIIA-131H/FcγRIIIB-NA2 haplotype had increased susceptibility to SMA (RR 1.47, 95% CI 1.06-2.04; P = 0.020). Results here demonstrate that variation in the FcγR gene alters susceptibility to repeated episodes of SMA and mortality, as well as functional changes in IFN-γ production.
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Affiliation(s)
- Collins Ouma
- Centre for Global Health Research, Kenya Medical Research Institute, University of New Mexico/KEMRI Laboratories of Parasitic and Viral Diseases, Kisumu, Kenya
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98
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Akdis M, Burgler S, Crameri R, Eiwegger T, Fujita H, Gomez E, Klunker S, Meyer N, O'Mahony L, Palomares O, Rhyner C, Ouaked N, Quaked N, Schaffartzik A, Van De Veen W, Zeller S, Zimmermann M, Akdis CA. Interleukins, from 1 to 37, and interferon-γ: receptors, functions, and roles in diseases. J Allergy Clin Immunol 2011; 127:701-21.e1-70. [PMID: 21377040 DOI: 10.1016/j.jaci.2010.11.050] [Citation(s) in RCA: 518] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 11/11/2010] [Accepted: 11/12/2010] [Indexed: 12/17/2022]
Abstract
Advancing our understanding of mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumor development, organ transplantation, and chronic infections could lead to effective and targeted therapies. Subsets of immune and inflammatory cells interact via ILs and IFNs; reciprocal regulation and counter balance among T(h) and regulatory T cells, as well as subsets of B cells, offer opportunities for immune interventions. Here, we review current knowledge about ILs 1 to 37 and IFN-γ. Our understanding of the effects of ILs has greatly increased since the discoveries of monocyte IL (called IL-1) and lymphocyte IL (called IL-2); more than 40 cytokines are now designated as ILs. Studies of transgenic or knockout mice with altered expression of these cytokines or their receptors and analyses of mutations and polymorphisms in human genes that encode these products have provided important information about IL and IFN functions. We discuss their signaling pathways, cellular sources, targets, roles in immune regulation and cellular networks, roles in allergy and asthma, and roles in defense against infections.
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Affiliation(s)
- Mübeccel Akdis
- Swiss Institute of Allergy and Asthma Research, University of Zurich, Davos, Switzerland.
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99
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Andrade BB, Santos CJN, Camargo LM, Souza-Neto SM, Reis-Filho A, Clarêncio J, Mendonça VRR, Luz NF, Camargo EP, Barral A, Silva AAM, Barral-Netto M. Hepatitis B infection is associated with asymptomatic malaria in the Brazilian Amazon. PLoS One 2011; 6:e19841. [PMID: 21625634 PMCID: PMC3097216 DOI: 10.1371/journal.pone.0019841] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 04/04/2011] [Indexed: 11/18/2022] Open
Abstract
Background Areas that are endemic for malaria are also highly endemic for hepatitis B virus (HBV) infection. Nevertheless, it is unknown whether HBV infection modifies the clinical presentation of malaria. This study aimed to address this question. Methodology and Findings An observational study of 636 individuals was performed in Rondônia, western Amazon, Brazil between 2006 and 2007. Active and passive case detections identified Plasmodium infection by field microscopy and nested Polymerase Chain Reaction (PCR). HBV infections were identified by serology and confirmed by real-time PCR. Epidemiological information and plasma cytokine profiles were studied. The data were analyzed using adjusted multinomial logistic regression. Plasmodium-infected individuals with active HBV infection were more likely to be asymptomatic (OR: 120.13, P<0.0001), present with lower levels of parasitemia and demonstrate a decreased inflammatory cytokine profile. Nevertheless, co-infected individuals presented higher HBV viremia. Plasmodium parasitemia inversely correlated with plasma HBV DNA levels (r = −0.6; P = 0.0003). Conclusion HBV infection diminishes the intensity of malaria infection in individuals from this endemic area. This effect seems related to cytokine balance and control of inflammatory responses. These findings add important insights to the understanding of the factors affecting the clinical outcomes of malaria in endemic regions.
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Affiliation(s)
- Bruno B. Andrade
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
| | - Cristiane J. N. Santos
- Departamento de Saúde Publica, Centro de Ciências da Saúde, Universidade Federal do Maranhão, São Luis, Brazil
| | - Luís M. Camargo
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
- Faculdade de Medicina, Faculdade São Lucas, Porto Velho, Brazil
| | - Sebastião M. Souza-Neto
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
| | - Antonio Reis-Filho
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
| | - Jorge Clarêncio
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Vitor R. R. Mendonça
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
| | - Nívea F. Luz
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
| | - Erney P. Camargo
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Aldina Barral
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
- Instituto de Investigação em Imunologia, Instituto Nacional de Ciência e Tecnologia (INCT), São Paulo, Brazil
| | - Antônio A. M. Silva
- Departamento de Saúde Publica, Centro de Ciências da Saúde, Universidade Federal do Maranhão, São Luis, Brazil
| | - Manoel Barral-Netto
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
- Faculdade de Medicina da Bahia, Universidade Federal da Bahia, Salvador, Brazil
- Instituto de Investigação em Imunologia, Instituto Nacional de Ciência e Tecnologia (INCT), São Paulo, Brazil
- * E-mail:
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100
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Metenou S, Dembele B, Konate S, Dolo H, Coulibaly YI, Diallo AA, Soumaoro L, Coulibaly ME, Coulibaly SY, Sanogo D, Doumbia SS, Traoré SF, Mahanty S, Klion A, Nutman TB. Filarial infection suppresses malaria-specific multifunctional Th1 and Th17 responses in malaria and filarial coinfections. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 186:4725-33. [PMID: 21411732 PMCID: PMC3407819 DOI: 10.4049/jimmunol.1003778] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The mechanisms underlying the modulation of both the malaria-specific immune response and the course of clinical malaria in the context of concomitant helminth infection are poorly understood. We used multiparameter flow cytometry to characterize the quality and the magnitude of malaria-specific T cell responses in filaria-infected and -uninfected individuals with concomitant asymptomatic Plasmodium falciparum malaria in Mali. In comparison with filarial-uninfected subjects, filarial infection was associated with higher ex vivo frequencies of CD4(+) cells producing IL-4, IL-10, and IL-17A (p = 0.01, p = 0.001, and p = 0.03, respectively). In response to malaria Ag stimulation, however, filarial infection was associated with lower frequencies of CD4(+) T cells producing IFN-γ, TNF-α, and IL-17A (p < 0.001, p = 0.04, and p = 0.04, respectively) and with higher frequencies of CD4(+)IL10(+)T cells (p = 0.0005). Importantly, filarial infection was associated with markedly lower frequencies of malaria Ag-specific Th1 (p < 0.0001), Th17 (p = 0.012), and "TNF-α" (p = 0.0008) cells, and a complete absence of malaria-specific multifunctional Th1 cells. Filarial infection was also associated with a marked increase in the frequency of malaria-specific adaptive regulatory T/Tr1 cells (p = 0.024), and the addition of neutralizing anti-IL-10 Ab augmented the amount of Th1-associated cytokine produced per cell. Thus, among malaria-infected individuals, concomitant filarial infection diminishes dramatically the frequencies of malaria-specific Th1 and Th17 T cells, and alters the quality and magnitude of malaria-specific T cell responses.
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Affiliation(s)
- Simon Metenou
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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