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Kamiya T, Davis NM, Greischar MA, Schneider D, Mideo N. Linking functional and molecular mechanisms of host resilience to malaria infection. eLife 2021; 10:e65846. [PMID: 34636723 PMCID: PMC8510579 DOI: 10.7554/elife.65846] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 08/16/2021] [Indexed: 12/30/2022] Open
Abstract
It remains challenging to understand why some hosts suffer severe illnesses, while others are unscathed by the same infection. We fitted a mathematical model to longitudinal measurements of parasite and red blood cell density in murine hosts from diverse genetic backgrounds to identify aspects of within-host interactions that explain variation in host resilience and survival during acute malaria infection. Among eight mouse strains that collectively span 90% of the common genetic diversity of laboratory mice, we found that high host mortality was associated with either weak parasite clearance, or a strong, yet imprecise response that inadvertently removes uninfected cells in excess. Subsequent cross-sectional cytokine assays revealed that the two distinct functional mechanisms of poor survival were underpinned by low expression of either pro- or anti-inflammatory cytokines, respectively. By combining mathematical modelling and molecular immunology assays, our study uncovered proximate mechanisms of diverse infection outcomes across multiple host strains and biological scales.
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Affiliation(s)
- Tsukushi Kamiya
- Department of Ecology and Evolutionary Biology, University of TorontoTorontoCanada
| | - Nicole M Davis
- Department of Microbiology and Immunology, Stanford UniversityStanfordUnited States
| | - Megan A Greischar
- Department of Ecology and Evolutionary Biology, Cornell UniversityIthacaUnited States
| | - David Schneider
- Department of Microbiology and Immunology, Stanford UniversityStanfordUnited States
| | - Nicole Mideo
- Department of Ecology and Evolutionary Biology, University of TorontoTorontoCanada
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2
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Westwood ML, O'Donnell AJ, Schneider P, Albery GF, Prior KF, Reece SE. Testing possible causes of gametocyte reduction in temporally out-of-synch malaria infections. Malar J 2020; 19:17. [PMID: 31937300 PMCID: PMC6958767 DOI: 10.1186/s12936-020-3107-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 01/07/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The intraerythrocytic development cycle (IDC) of the rodent malaria Plasmodium chabaudi is coordinated with host circadian rhythms. When this coordination is disrupted, parasites suffer a 50% reduction in both asexual stages and sexual stage gametocytes over the acute phase of infection. Reduced gametocyte density may not simply follow from a loss of asexuals because investment into gametocytes ("conversion rate") is a plastic trait; furthermore, the densities of both asexuals and gametocytes are highly dynamic during infection. Hence, the reasons for the reduction of gametocytes in infections that are out-of-synch with host circadian rhythms remain unclear. Here, two explanations are tested: first, whether out-of-synch parasites reduce their conversion rate to prioritize asexual replication via reproductive restraint; second, whether out-of-synch gametocytes experience elevated clearance by the host's circadian immune responses. METHODS First, conversion rate data were analysed from a previous experiment comparing infections of P. chabaudi that were in-synch or 12 h out-of-synch with host circadian rhythms. Second, three new experiments examined whether the inflammatory cytokine TNF varies in its gametocytocidal efficacy according to host time-of-day and gametocyte age. RESULTS There was no evidence that parasites reduce conversion or that their gametocytes become more vulnerable to TNF when out-of-synch with host circadian rhythms. CONCLUSIONS The factors causing the reduction of gametocytes in out-of-synch infections remain mysterious. Candidates for future investigation include alternative rhythmic factors involved in innate immune responses and the rhythmicity in essential resources required for gametocyte development. Explaining why it matters for gametocytes to be synchronized to host circadian rhythms might suggest novel approaches to blocking transmission.
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Affiliation(s)
- Mary L Westwood
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK.
| | - Aidan J O'Donnell
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK
| | - Petra Schneider
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK
| | - Gregory F Albery
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK
- Department of Biology, Georgetown University, 37th and O Streets NW, Washington, DC, 20057, USA
| | - Kimberley F Prior
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK
| | - Sarah E Reece
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, UK
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3
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Wale N, Jones MJ, Sim DG, Read AF, King AA. The contribution of host cell-directed vs. parasite-directed immunity to the disease and dynamics of malaria infections. Proc Natl Acad Sci U S A 2019; 116:22386-22392. [PMID: 31615885 PMCID: PMC6825298 DOI: 10.1073/pnas.1908147116] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hosts defend themselves against pathogens by mounting an immune response. Fully understanding the immune response as a driver of host disease and pathogen evolution requires a quantitative account of its impact on parasite population dynamics. Here, we use a data-driven modeling approach to quantify the birth and death processes underlying the dynamics of infections of the rodent malaria parasite, Plasmodium chabaudi, and the red blood cells (RBCs) it targets. We decompose the immune response into 3 components, each with a distinct effect on parasite and RBC vital rates, and quantify the relative contribution of each component to host disease and parasite density. Our analysis suggests that these components are deployed in a coordinated fashion to realize distinct resource-directed defense strategies that complement the killing of parasitized cells. Early in the infection, the host deploys a strategy reminiscent of siege and scorched-earth tactics, in which it both destroys RBCs and restricts their supply. Late in the infection, a "juvenilization" strategy, in which turnover of RBCs is accelerated, allows the host to recover from anemia while holding parasite proliferation at bay. By quantifying the impact of immunity on both parasite fitness and host disease, we reveal that phenomena often interpreted as immunopathology may in fact be beneficial to the host. Finally, we show that, across mice, the components of the host response are consistently related to each other, even when infections take qualitatively different trajectories. This suggests the existence of simple rules that govern the immune system's deployment.
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Affiliation(s)
- Nina Wale
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109;
| | - Matthew J Jones
- Center for Infectious Disease Dynamics, Huck Institutes for the Life Sciences, Pennsylvania State University, University Park, PA 16802
| | - Derek G Sim
- Center for Infectious Disease Dynamics, Huck Institutes for the Life Sciences, Pennsylvania State University, University Park, PA 16802
| | - Andrew F Read
- Center for Infectious Disease Dynamics, Huck Institutes for the Life Sciences, Pennsylvania State University, University Park, PA 16802
- Department of Biology, Pennsylvania State University, University Park, PA 16802
- Department of Entomology, Pennsylvania State University, University Park, PA 16802
| | - Aaron A King
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109
- Center for the Study of Complex Systems, University of Michigan, Ann Arbor, MI 48109
- Department of Mathematics, University of Michigan, Ann Arbor, MI 48109
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4
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Alamer E, Carpio VH, Ibitokou SA, Kirtley ML, Phoenix IR, Opata MM, Wilson KD, Cong Y, Dann SM, Chopra AK, Stephens R. Dissemination of non-typhoidal Salmonella during Plasmodium chabaudi infection affects anti-malarial immunity. Parasitol Res 2019; 118:2277-2285. [PMID: 31119381 DOI: 10.1007/s00436-019-06349-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 05/09/2019] [Indexed: 01/18/2023]
Abstract
Malaria-associated bacteremia accounts for up to one-third of deaths from severe malaria, and non-typhoidal Salmonella (NTS) has been reported as a major complication of severe malarial infection. Patients who develop NTS bacteremia during Plasmodium infection show higher mortality rates than individuals with malaria alone. Systemic bacteremia can be caused by a wound or translocation from epithelial or endothelial sites. NTS is an intestinal pathogen, however the contribution of bacterial translocation from the intestinal tract during Plasmodium infection is not well studied. Here, we investigated the integrity of the intestinal barrier function of P. chabaudi-infected mice using large molecules and Salmonella infection. Intestinal histology and the adaptive immune response to malaria were also studied using light microscopy and flow cytometry. P. chabaudi infection compromised intestinal barrier function, which led to increased intestinal cellular infiltration. In addition, we observed increased serum lipopolysaccharide binding protein and leakage of soluble molecules from the intestine into the blood in infected mice. Plasmodium infection also increased intestinal translocation and dissemination of NTS to the liver. The adaptive immune response to P. chabaudi infection was also significantly impacted by NTS translocation. Reduced B and T cell activation were observed in co-infected animals, suggesting interference in the malaria-specific immune responses by bacteremia. These studies demonstrate that P. chabaudi infection induces failure of the barrier function of the intestinal wall and enhanced intestinal bacterial translocation, affecting anti-malarial immunity.
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Affiliation(s)
- Edrous Alamer
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
- Department of Medical Laboratories Technology, College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Victor H Carpio
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Samad A Ibitokou
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Michelle L Kirtley
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Inaia R Phoenix
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Michael M Opata
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Kyle D Wilson
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Yingzi Cong
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Sara M Dann
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Ashok K Chopra
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Robin Stephens
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA.
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA.
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5
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Akter J, Khoury DS, Aogo R, Lansink LIM, SheelaNair A, Thomas BS, Laohamonthonkul P, Pernold CPS, Dixon MWA, Soon MSF, Fogg LG, Engel JA, Elliott T, Sebina I, James KR, Cromer D, Davenport MP, Haque A. Plasmodium-specific antibodies block in vivo parasite growth without clearing infected red blood cells. PLoS Pathog 2019; 15:e1007599. [PMID: 30811498 PMCID: PMC6411214 DOI: 10.1371/journal.ppat.1007599] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 03/11/2019] [Accepted: 01/28/2019] [Indexed: 01/01/2023] Open
Abstract
Plasmodium parasites invade and multiply inside red blood cells (RBC). Through a cycle of maturation, asexual replication, rupture and release of multiple infective merozoites, parasitised RBC (pRBC) can reach very high numbers in vivo, a process that correlates with disease severity in humans and experimental animals. Thus, controlling pRBC numbers can prevent or ameliorate malaria. In endemic regions, circulating parasite-specific antibodies associate with immunity to high parasitemia. Although in vitro assays reveal that protective antibodies could control pRBC via multiple mechanisms, in vivo assessment of antibody function remains challenging. Here, we employed two mouse models of antibody-mediated immunity to malaria, P. yoelii 17XNL and P. chabaudi chabaudi AS infection, to study infection-induced, parasite-specific antibody function in vivo. By tracking a single generation of pRBC, we tested the hypothesis that parasite-specific antibodies accelerate pRBC clearance. Though strongly protective against homologous re-challenge, parasite-specific IgG did not alter the rate of pRBC clearance, even in the presence of ongoing, systemic inflammation. Instead, antibodies prevented parasites progressing from one generation of RBC to the next. In vivo depletion studies using clodronate liposomes or cobra venom factor, suggested that optimal antibody function required splenic macrophages and dendritic cells, but not complement C3/C5-mediated killing. Finally, parasite-specific IgG bound poorly to the surface of pRBC, yet strongly to structures likely exposed by the rupture of mature schizonts. Thus, in our models of humoral immunity to malaria, infection-induced antibodies did not accelerate pRBC clearance, and instead co-operated with splenic phagocytes to block subsequent generations of pRBC. Malaria occurs when Plasmodium parasites replicate inside red blood cells, with the number of parasitised cells (pRBC) correlating with disease severity. Antibodies are highly effective at controlling pRBC numbers in the bloodstream, and yet we know very little about how they function in vivo. Human in vitro studies predict that antibodies may function in a number of ways, including via phagocytes or different complement mechanisms. However, to date it has been challenging to explore how antibodies might control parasite numbers in vivo. Here, we have used a unique method in mice, where clearance and replication of a single cohort of pRBC was closely tracked in the presence of protective antibodies. Surprisingly, antibodies played no role whatsoever in accelerating the removal of pRBC. Instead, antibodies were highly effective at preventing parasites from progressing from one generation of pRBC to the next. This process partly depended on host phagocytes. However, we found no role for complement-mediated direct killing. Together, our in vivo data suggest in mouse models that naturally-acquired antibodies do not clear pRBC, and instead prevent transition from one red blood cell to the next.
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Affiliation(s)
- Jasmin Akter
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - David S. Khoury
- Infection Analytics Program, Kirby Institute, UNSW Australia, Kensington NSW, Australia
| | - Rosemary Aogo
- Infection Analytics Program, Kirby Institute, UNSW Australia, Kensington NSW, Australia
| | | | - Arya SheelaNair
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Bryce S. Thomas
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | | | | | - Matthew W. A. Dixon
- University of Melbourne, Department of Biochemistry and Molecular Biology, Melbourne, Victoria, Australia
| | - Megan S. F. Soon
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Lily G. Fogg
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Jessica A. Engel
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Trish Elliott
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Ismail Sebina
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Kylie R. James
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
| | - Deborah Cromer
- Infection Analytics Program, Kirby Institute, UNSW Australia, Kensington NSW, Australia
| | - Miles P. Davenport
- Infection Analytics Program, Kirby Institute, UNSW Australia, Kensington NSW, Australia
- * E-mail: (MPD); (AH)
| | - Ashraful Haque
- QIMR Berghofer Medical Research Institute, Herston, Brisbane QLD, Australia
- * E-mail: (MPD); (AH)
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6
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Borges da Silva H, Machado de Salles É, Lima-Mauro EF, Sardinha LR, Álvarez JM, D’Império Lima MR. CD28 deficiency leads to accumulation of germinal-center independent IgM+ experienced B cells and to production of protective IgM during experimental malaria. PLoS One 2018; 13:e0202522. [PMID: 30148845 PMCID: PMC6110469 DOI: 10.1371/journal.pone.0202522] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 08/03/2018] [Indexed: 12/04/2022] Open
Abstract
Protective immunity to blood-stage malaria is attributed to Plasmodium-specific IgG and effector-memory T helper 1 (Th1) cells. However, mice lacking the costimulatory receptor CD28 (CD28KO) maintain chronic parasitemia at low levels and do not succumb to infection, suggesting that other immune responses contribute to parasite control. We report here that CD28KO mice develop long-lasting non-sterile immunity and survive lethal parasite challenge. This protection correlated with a progressive increase of anti-parasite IgM serum levels during chronic infection. Serum IgM from chronically infected CD28KO mice recognize erythrocytes infected with mature parasites, and effectively control Plasmodium infection by promoting parasite lysis and uptake. These antibodies also recognize autoantigens and antigens from other pathogens. Chronically infected CD28KO mice have high numbers of IgM+ plasmocytes and experienced B cells, exhibiting a germinal-center independent Fas+GL7-CD38+CD73- phenotype. These cells are also present in chronically infected C57BL/6 mice although in lower numbers. Finally, IgM+ experienced B cells from cured C57BL/6 and CD28KO mice proliferate and produce anti-parasite IgM in response to infected erythrocytes. This study demonstrates that CD28 deficiency results in the generation of germinal-center independent IgM+ experienced B cells and the production of protective IgM during experimental malaria, providing evidence for an additional mechanism by which the immune system controls Plasmodium infection.
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Affiliation(s)
- Henrique Borges da Silva
- Departamento de Imunologia, Instituto de Ciências Biomédicas (ICB), Universidade de São Paulo (USP), São Paulo, Brazil
- * E-mail: (HBdS); (MRDL)
| | - Érika Machado de Salles
- Departamento de Imunologia, Instituto de Ciências Biomédicas (ICB), Universidade de São Paulo (USP), São Paulo, Brazil
| | | | | | - José Maria Álvarez
- Departamento de Imunologia, Instituto de Ciências Biomédicas (ICB), Universidade de São Paulo (USP), São Paulo, Brazil
| | - Maria Regina D’Império Lima
- Departamento de Imunologia, Instituto de Ciências Biomédicas (ICB), Universidade de São Paulo (USP), São Paulo, Brazil
- * E-mail: (HBdS); (MRDL)
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7
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Opata MM, Ibitokou SA, Carpio VH, Marshall KM, Dillon BE, Carl JC, Wilson KD, Arcari CM, Stephens R. Protection by and maintenance of CD4 effector memory and effector T cell subsets in persistent malaria infection. PLoS Pathog 2018; 14:e1006960. [PMID: 29630679 PMCID: PMC5908200 DOI: 10.1371/journal.ppat.1006960] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 04/19/2018] [Accepted: 03/04/2018] [Indexed: 01/12/2023] Open
Abstract
Protection at the peak of Plasmodium chabaudi blood-stage malaria infection is provided by CD4 T cells. We have shown that an increase in Th1 cells also correlates with protection during the persistent phase of malaria; however, it is unclear how these T cells are maintained. Persistent malaria infection promotes protection and generates both effector T cells (Teff), and effector memory T cells (Tem). We have previously defined new CD4 Teff (IL-7Rα-) subsets from Early (TeffEarly, CD62LhiCD27+) to Late (TeffLate, CD62LloCD27-) activation states. Here, we tested these effector and memory T cell subsets for their ability to survive and protect in vivo. We found that both polyclonal and P. chabaudi Merozoite Surface Protein-1 (MSP-1)-specific B5 TCR transgenic Tem survive better than Teff. Surprisingly, as Tem are associated with antigen persistence, Tem survive well even after clearance of infection. As previously shown during T cell contraction, TeffEarly, which can generate Tem, also survive better than other Teff subsets in uninfected recipients. Two other Tem survival mechanisms identified here are that low-level chronic infection promotes Tem both by driving their proliferation, and by programming production of Tem from Tcm. Protective CD4 T cell phenotypes have not been precisely determined in malaria, or other persistent infections. Therefore, we tested purified memory (Tmem) and Teff subsets in protection from peak pathology and parasitemia in immunocompromised recipient mice. Strikingly, among Tmem (IL-7Rαhi) subsets, only TemLate (CD62LloCD27-) reduced peak parasitemia (19%), though the dominant memory subset is TemEarly, which is not protective. In contrast, all Teff subsets reduced peak parasitemia by more than half, and mature Teff can generate Tem, though less. In summary, we have elucidated four mechanisms of Tem maintenance, and identified two long-lived T cell subsets (TemLate, TeffEarly) that may represent correlates of protection or a target for longer-lived vaccine-induced protection against malaria blood-stages. Malaria causes significant mortality but current vaccine candidates have poor efficacy and duration, as does natural immunity to malaria. T helper cells (CD4+) are essential to protection from malaria, but it is unknown what kinds of T cells would be both protective and long-lasting. Here, we explored the mechanisms of survival used by memory T cells in malaria, and their ability to protect immunodeficient animals from malaria. We identified four mechanisms by which memory T cells are maintained in chronic infection. We also showed that highly activated effector T cells protect better than memory T cells in general, however, effector T cells have a shorter lifespan suggesting a mechanism for short-lived immunity. In total, we identified two protective T cell subsets that are long-lived. Unfortunately, the memory T cell subset that protects, is not the predominant memory T cell population generated by natural infection, suggesting a mechanism for the poor immunity seen in malaria. Our work suggests that vaccines that induce these two T cell subsets may improve on current immunity from malaria infection and disease.
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Affiliation(s)
- Michael M. Opata
- Departments of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Samad A. Ibitokou
- Departments of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Victor H. Carpio
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Karis M. Marshall
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Brian E. Dillon
- Departments of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Jordan C. Carl
- Departments of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Kyle D. Wilson
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Christine M. Arcari
- Department of Preventive Medicine & Community Health, University of Texas Medical Branch Galveston, TX, United States of America
| | - Robin Stephens
- Departments of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States of America
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States of America
- * E-mail:
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8
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Fontana MF, de Melo GL, Anidi C, Hamburger R, Kim CY, Lee SY, Pham J, Kim CC. Macrophage Colony Stimulating Factor Derived from CD4+ T Cells Contributes to Control of a Blood-Borne Infection. PLoS Pathog 2016; 12:e1006046. [PMID: 27923070 PMCID: PMC5140069 DOI: 10.1371/journal.ppat.1006046] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Accepted: 11/07/2016] [Indexed: 12/18/2022] Open
Abstract
Dynamic regulation of leukocyte population size and activation state is crucial for an effective immune response. In malaria, Plasmodium parasites elicit robust host expansion of macrophages and monocytes, but the underlying mechanisms remain unclear. Here we show that myeloid expansion during P. chabaudi infection is dependent upon both CD4+ T cells and the cytokine Macrophage Colony Stimulating Factor (MCSF). Single-cell RNA-Seq analysis on antigen-experienced T cells revealed robust expression of Csf1, the gene encoding MCSF, in a sub-population of CD4+ T cells with distinct transcriptional and surface phenotypes. Selective deletion of Csf1 in CD4+ cells during P. chabaudi infection diminished proliferation and activation of certain myeloid subsets, most notably lymph node-resident CD169+ macrophages, and resulted in increased parasite burden and impaired recovery of infected mice. Depletion of CD169+ macrophages during infection also led to increased parasitemia and significant host mortality, confirming a previously unappreciated role for these cells in control of P. chabaudi. This work establishes the CD4+ T cell as a physiologically relevant source of MCSF in vivo; probes the complexity of the CD4+ T cell response during type 1 infection; and delineates a novel mechanism by which T helper cells regulate myeloid cells to limit growth of a blood-borne intracellular pathogen.
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Affiliation(s)
- Mary F. Fontana
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
- * E-mail: (MFF); (CCK)
| | - Gabrielly L. de Melo
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
| | - Chioma Anidi
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
| | - Rebecca Hamburger
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
| | - Chris Y. Kim
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
| | - So Youn Lee
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
| | - Jennifer Pham
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
| | - Charles C. Kim
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States of America
- * E-mail: (MFF); (CCK)
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9
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Sebina I, James KR, Soon MSF, Fogg LG, Best SE, de Labastida Rivera F, Montes de Oca M, Amante FH, Thomas BS, Beattie L, Souza-Fonseca-Guimaraes F, Smyth MJ, Hertzog PJ, Hill GR, Hutloff A, Engwerda CR, Haque A. IFNAR1-Signalling Obstructs ICOS-mediated Humoral Immunity during Non-lethal Blood-Stage Plasmodium Infection. PLoS Pathog 2016; 12:e1005999. [PMID: 27812214 PMCID: PMC5094753 DOI: 10.1371/journal.ppat.1005999] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 10/13/2016] [Indexed: 01/19/2023] Open
Abstract
Parasite-specific antibodies protect against blood-stage Plasmodium infection. However, in malaria-endemic regions, it takes many months for naturally-exposed individuals to develop robust humoral immunity. Explanations for this have focused on antigenic variation by Plasmodium, but have considered less whether host production of parasite-specific antibody is sub-optimal. In particular, it is unclear whether host immune factors might limit antibody responses. Here, we explored the effect of Type I Interferon signalling via IFNAR1 on CD4+ T-cell and B-cell responses in two non-lethal murine models of malaria, P. chabaudi chabaudi AS (PcAS) and P. yoelii 17XNL (Py17XNL) infection. Firstly, we demonstrated that CD4+ T-cells and ICOS-signalling were crucial for generating germinal centre (GC) B-cells, plasmablasts and parasite-specific antibodies, and likewise that T follicular helper (Tfh) cell responses relied on B cells. Next, we found that IFNAR1-signalling impeded the resolution of non-lethal blood-stage infection, which was associated with impaired production of parasite-specific IgM and several IgG sub-classes. Consistent with this, GC B-cell formation, Ig-class switching, plasmablast and Tfh differentiation were all impaired by IFNAR1-signalling. IFNAR1-signalling proceeded via conventional dendritic cells, and acted early by limiting activation, proliferation and ICOS expression by CD4+ T-cells, by restricting the localization of activated CD4+ T-cells adjacent to and within B-cell areas of the spleen, and by simultaneously suppressing Th1 and Tfh responses. Finally, IFNAR1-deficiency accelerated humoral immune responses and parasite control by boosting ICOS-signalling. Thus, we provide evidence of a host innate cytokine response that impedes the onset of humoral immunity during experimental malaria. Plasmodium parasites cause malaria by invading, replicating within, and rupturing out of red blood cells. Natural immunity to malaria, which depends on generating Plasmodium-specific antibodies, often takes years to develop. Explanations for this focus on antigenic variation by the parasite, but consider less whether antibody responses themselves may be sub-optimal. Surprisingly little is known about how Plasmodium-specific antibody responses are generated in the host, and whether these can be enhanced. Using mouse models, we found that cytokine-signalling via the receptor IFNAR1 delayed the production of Plasmodium-specific antibody responses. IFNAR1-signalling hindered the resolution of infection, and acted early via conventional dendritic cells to restrict CD4+ T-cell activation and their interactions with B-cells. Thus, we reveal that an innate cytokine response, which occurs during blood-stage Plasmodium infection in humans, obstructs the onset of antibody–mediated immunity during experimental malaria.
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Affiliation(s)
- Ismail Sebina
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- The University of Queensland, School of Medicine PhD Program, Herston, Queensland, Australia
| | - Kylie R. James
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- The University of Queensland, School of Medicine PhD Program, Herston, Queensland, Australia
| | - Megan S. F. Soon
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Lily G. Fogg
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Shannon E. Best
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Fabian de Labastida Rivera
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Marcela Montes de Oca
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Fiona H. Amante
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Bryce S. Thomas
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Lynette Beattie
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | | | - Mark J. Smyth
- Immunity in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute Herston, Queensland, Australia
| | - Paul J. Hertzog
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Geoffrey R. Hill
- Bone Marrow Transplantation Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Andreas Hutloff
- Chronic Immune Reactions, German Rheumatism Research Centre (DRFZ), a Leibniz Institute, Berlin, Germany
| | - Christian R. Engwerda
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Ashraful Haque
- Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- * E-mail:
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Coomes SM, Pelly VS, Kannan Y, Okoye IS, Czieso S, Entwistle LJ, Perez-Lloret J, Nikolov N, Potocnik AJ, Biró J, Langhorne J, Wilson MS. IFNγ and IL-12 Restrict Th2 Responses during Helminth/Plasmodium Co-Infection and Promote IFNγ from Th2 Cells. PLoS Pathog 2015; 11:e1004994. [PMID: 26147567 PMCID: PMC4493106 DOI: 10.1371/journal.ppat.1004994] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 06/02/2015] [Indexed: 12/19/2022] Open
Abstract
Parasitic helminths establish chronic infections in mammalian hosts. Helminth/Plasmodium co-infections occur frequently in endemic areas. However, it is unclear whether Plasmodium infections compromise anti-helminth immunity, contributing to the chronicity of infection. Immunity to Plasmodium or helminths requires divergent CD4+ T cell-driven responses, dominated by IFNγ or IL-4, respectively. Recent literature has indicated that Th cells, including Th2 cells, have phenotypic plasticity with the ability to produce non-lineage associated cytokines. Whether such plasticity occurs during co-infection is unclear. In this study, we observed reduced anti-helminth Th2 cell responses and compromised anti-helminth immunity during Heligmosomoides polygyrus and Plasmodium chabaudi co-infection. Using newly established triple cytokine reporter mice (Il4gfpIfngyfpIl17aFP635), we demonstrated that Il4gfp+ Th2 cells purified from in vitro cultures or isolated ex vivo from helminth-infected mice up-regulated IFNγ following adoptive transfer into Rag1–/– mice infected with P. chabaudi. Functionally, Th2 cells that up-regulated IFNγ were transcriptionally re-wired and protected recipient mice from high parasitemia. Mechanistically, TCR stimulation and responsiveness to IL-12 and IFNγ, but not type I IFN, was required for optimal IFNγ production by Th2 cells. Finally, blockade of IL-12 and IFNγ during co-infection partially preserved anti-helminth Th2 responses. In summary, this study demonstrates that Th2 cells retain substantial plasticity with the ability to produce IFNγ during Plasmodium infection. Consequently, co-infection with Plasmodium spp. may contribute to the chronicity of helminth infection by reducing anti-helminth Th2 cells and converting them into IFNγ-secreting cells. Approximately a third of the world’s population is burdened with chronic intestinal parasitic helminth infections, causing significant morbidities. Identifying the factors that contribute to the chronicity of infection is therefore essential. Co-infection with other pathogens, which is extremely common in helminth endemic areas, may contribute to the chronicity of helminth infections. In this study, we used a mouse model to test whether the immune responses to an intestinal helminth were impaired following malaria co-infection. These two pathogens induce very different immune responses, which, until recently, were thought to be opposing and non-interchangeable. This study identified that the immune cells required for anti-helminth responses are capable of changing their phenotype and providing protection against malaria. By identifying and blocking the factors that drive this change in phenotype, we can preserve anti-helminth immune responses during co-infection. Our studies provide fresh insight into how immune responses are altered during helminth and malaria co-infection.
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Affiliation(s)
- Stephanie M. Coomes
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Victoria S. Pelly
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Yashaswini Kannan
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Isobel S. Okoye
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Stephanie Czieso
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Lewis J. Entwistle
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Jimena Perez-Lloret
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Nikolay Nikolov
- Division of Systems Biology, The Francis Crick Institute, London, United Kingdom
| | - Alexandre J. Potocnik
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Judit Biró
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
| | - Jean Langhorne
- Division of Parasitology, Mill Hill Laboratories, London, United Kingdom
| | - Mark S. Wilson
- Division of Molecular Immunology, The Francis Crick Institute, London, United Kingdom
- * E-mail:
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11
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Pérez-Mazliah D, Ng DHL, Freitas do Rosário AP, McLaughlin S, Mastelic-Gavillet B, Sodenkamp J, Kushinga G, Langhorne J. Disruption of IL-21 signaling affects T cell-B cell interactions and abrogates protective humoral immunity to malaria. PLoS Pathog 2015; 11:e1004715. [PMID: 25763578 PMCID: PMC4370355 DOI: 10.1371/journal.ppat.1004715] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 01/29/2015] [Indexed: 12/22/2022] Open
Abstract
Interleukin-21 signaling is important for germinal center B-cell responses, isotype switching and generation of memory B cells. However, a role for IL-21 in antibody-mediated protection against pathogens has not been demonstrated. Here we show that IL-21 is produced by T follicular helper cells and co-expressed with IFN-γ during an erythrocytic-stage malaria infection of Plasmodium chabaudi in mice. Mice deficient either in IL-21 or the IL-21 receptor fail to resolve the chronic phase of P. chabaudi infection and P. yoelii infection resulting in sustained high parasitemias, and are not immune to re-infection. This is associated with abrogated P. chabaudi-specific IgG responses, including memory B cells. Mixed bone marrow chimeric mice, with T cells carrying a targeted disruption of the Il21 gene, or B cells with a targeted disruption of the Il21r gene, demonstrate that IL-21 from T cells signaling through the IL-21 receptor on B cells is necessary to control chronic P. chabaudi infection. Our data uncover a mechanism by which CD4+ T cells and B cells control parasitemia during chronic erythrocytic-stage malaria through a single gene, Il21, and demonstrate the importance of this cytokine in the control of pathogens by humoral immune responses. These data are highly pertinent for designing malaria vaccines requiring long-lasting protective B-cell responses. The importance of antibody and B-cell responses for control of the erythrocytic-stage of the malaria parasite, Plasmodium, was first described when immune serum, passively transferred into Plasmodium falciparum-infected children, reduced parasitemia. This was later confirmed in experimental models in which mice deficient in B cells were unable to eliminate erythrocytic-stage infections. The signals required to activate these protective long-lasting B cell responses towards Plasmodium have not been investigated. IL-21 has been shown to be important for development of B-cell responses after immunization; however, a direct requirement for IL-21 in the control of infection via B-cell dependent mechanisms has never been demonstrated. In this paper, we have used mouse models of erythrocytic P. chabaudi and P. yoelii 17X(NL) infections in combination with IL-21/IL-21R deficiency to show that IL-21 from CD4+ T cells is required to eliminate Plasmodium infection by activating protective, long-lasting B-cell responses. Disruption of IL-21 signaling in B cells prevents the elimination of the parasite resulting in sustained high parasitemias, with no development of memory B-cells, lack of antigen-specific plasma cells and antibodies, and thus no protective immunity against a second challenge infection. Our data demonstrate the absolute requirement of IL-21 for B-cell control of this systemic infection. This has important implications for the design of vaccines against Plasmodium.
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Affiliation(s)
- Damián Pérez-Mazliah
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
| | - Dorothy Hui Lin Ng
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
| | | | - Sarah McLaughlin
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
| | - Béatris Mastelic-Gavillet
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
| | - Jan Sodenkamp
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
| | - Garikai Kushinga
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
| | - Jean Langhorne
- Division of Parasitology, MRC National Institute for Medical Research (NIMR), London, United Kingdom
- * E-mail:
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12
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Brugat T, Cunningham D, Sodenkamp J, Coomes S, Wilson M, Spence PJ, Jarra W, Thompson J, Scudamore C, Langhorne J. Sequestration and histopathology in Plasmodium chabaudi malaria are influenced by the immune response in an organ-specific manner. Cell Microbiol 2014; 16:687-700. [PMID: 24003897 PMCID: PMC4234010 DOI: 10.1111/cmi.12212] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 07/26/2013] [Accepted: 08/26/2013] [Indexed: 11/28/2022]
Abstract
Infection with the malaria parasite, Plasmodium, is associated with a strong inflammatory response and parasite cytoadhesion (sequestration) in several organs. Here, we have carried out a systematic study of sequestration and histopathology during infection of C57Bl/6 mice with Plasmodium chabaudi AS and determined the influence of the immune response. This parasite sequesters predominantly in liver and lung, but not in the brain, kidney or gut. Histopathological changes occur in multiple organs during the acute infection, but are not restricted to the organs where sequestration takes place. Adaptive immunity, and signalling through the IFNγ receptor increased sequestration and histopathology in the liver, but not in the lung, suggesting that there are differences in the adhesion molecules and/or parasite ligands utilized and mechanisms of pathogenesis in these two organs. Exacerbation of pro-inflammatory responses during infection by deletion of the il10 gene resultsin the aggravation of damage to lung and kidney irrespective of the degree of sequestration. The immune response therefore affected both sequestration and histopathology in an organ-specific manner. P. chabaudi AS provides a good model to investigate the influence of the host response on the sequestration and specific organ pathology, which is applicable to human malaria.
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Affiliation(s)
- Thibaut Brugat
- Division of Parasitology, MRC National Institute for Medical Research, London, NW7 1AA, UK
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13
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Abstract
A recent study found that mosquito-transmitted (MT) lines of rodent malaria parasites elicit a more effective immune response than non-transmitted lines maintained by serial blood passage (non-MT), thereby causing lower parasite densities in the blood and less pathology to the host. The authors attribute these changes to higher diversity in expression of antigen-encoding genes in MT cf. non-MT lines. Alternative explanations that are equally parsimonious with these new data, and results from previous studies, suggest that this conclusion may be premature.
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14
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Ataide MA, Andrade WA, Zamboni DS, Wang D, Souza MDC, Franklin BS, Elian S, Martins FS, Pereira D, Reed G, Fitzgerald KA, Golenbock DT, Gazzinelli RT. Malaria-induced NLRP12/NLRP3-dependent caspase-1 activation mediates inflammation and hypersensitivity to bacterial superinfection. PLoS Pathog 2014; 10:e1003885. [PMID: 24453977 PMCID: PMC3894209 DOI: 10.1371/journal.ppat.1003885] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 11/29/2013] [Indexed: 12/20/2022] Open
Abstract
Cyclic paroxysm and high fever are hallmarks of malaria and are associated with high levels of pyrogenic cytokines, including IL-1β. In this report, we describe a signature for the expression of inflammasome-related genes and caspase-1 activation in malaria. Indeed, when we infected mice, Plasmodium infection was sufficient to promote MyD88-mediated caspase-1 activation, dependent on IFN-γ-priming and the expression of inflammasome components ASC, P2X7R, NLRP3 and/or NLRP12. Pro-IL-1β expression required a second stimulation with LPS and was also dependent on IFN-γ-priming and functional TNFR1. As a consequence of Plasmodium-induced caspase-1 activation, mice produced extremely high levels of IL-1β upon a second microbial stimulus, and became hypersensitive to septic shock. Therapeutic intervention with IL-1 receptor antagonist prevented bacterial-induced lethality in rodents. Similar to mice, we observed a significantly increased frequency of circulating CD14+CD16−Caspase-1+ and CD14dimCD16+Caspase-1+ monocytes in peripheral blood mononuclear cells from febrile malaria patients. These cells readily produced large amounts of IL-1β after stimulation with LPS. Furthermore, we observed the presence of inflammasome complexes in monocytes from malaria patients containing either NLRP3 or NLRP12 pyroptosomes. We conclude that NLRP12/NLRP3-dependent activation of caspase-1 is likely to be a key event in mediating systemic production of IL-1β and hypersensitivity to secondary bacterial infection during malaria. Together Plasmodium falciparum and P. vivax infect approximately 250 million individuals, reaping life of near one million children every year. Extensive research on malaria pathogenesis has funneled into the consensus that the clinical manifestations are often a consequence of the systemic inflammation. Importantly, secondary bacterial and viral infections potentiate this inflammatory reaction being important co-factors for the development of severe disease. One of the hallmarks of malaria syndrome is the paroxysm, which is characterized by high fever associated with peak of parasitemia. In this study we dissected the mechanisms of induction and the importance of the pyrogenic cytokine, IL-1β in the pathogenesis of malaria. Our results demonstrate the critical role of the innate immune receptors named Toll-Like Receptors and inflammasome on induction, processing and release of active form of IL-1β during malaria. Importantly, we provide evidences that bacterial superinfection further potentiates the Plasmodium-induced systemic inflammation, leading to the release of bulk amounts of IL-1β and severe disease. Hence, this study uncovers new checkpoints that could be targeted for preventing systemic inflammation and severe malaria.
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MESH Headings
- Animals
- Bacterial Infections/genetics
- Bacterial Infections/immunology
- Bacterial Infections/metabolism
- Carrier Proteins/genetics
- Carrier Proteins/immunology
- Carrier Proteins/metabolism
- Caspase 1/genetics
- Caspase 1/immunology
- Caspase 1/metabolism
- Female
- Humans
- Inflammasomes/genetics
- Inflammasomes/immunology
- Inflammasomes/metabolism
- Inflammation/genetics
- Inflammation/immunology
- Inflammation/metabolism
- Inflammation/pathology
- Interleukin-1beta/genetics
- Interleukin-1beta/immunology
- Intracellular Signaling Peptides and Proteins/genetics
- Intracellular Signaling Peptides and Proteins/immunology
- Intracellular Signaling Peptides and Proteins/metabolism
- Malaria, Vivax/immunology
- Malaria, Vivax/metabolism
- Malaria, Vivax/microbiology
- Malaria, Vivax/pathology
- Male
- Mice
- Mice, Knockout
- Monocytes/immunology
- Monocytes/metabolism
- Monocytes/pathology
- NLR Family, Pyrin Domain-Containing 3 Protein
- Plasmodium chabaudi/immunology
- Plasmodium chabaudi/metabolism
- Plasmodium vivax/immunology
- Plasmodium vivax/metabolism
- Shock, Septic/genetics
- Shock, Septic/immunology
- Shock, Septic/metabolism
- Shock, Septic/pathology
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Affiliation(s)
- Marco A. Ataide
- Laboratório de Imunopatologia, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Warrison A. Andrade
- Laboratório de Imunopatologia, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Dario S. Zamboni
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Donghai Wang
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Maria do Carmo Souza
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Bernardo S. Franklin
- Laboratório de Imunopatologia, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
| | - Samir Elian
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Flaviano S. Martins
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Dhelio Pereira
- Centro de Pesquisas em Medicina Tropical, Porto Velho, Rondônia, Brazil
| | - George Reed
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Katherine A. Fitzgerald
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Douglas T. Golenbock
- Laboratório de Imunopatologia, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Ricardo T. Gazzinelli
- Laboratório de Imunopatologia, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- * E-mail:
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15
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Ng DHL, Skehel JJ, Kassiotis G, Langhorne J. Recovery of an antiviral antibody response following attrition caused by unrelated infection. PLoS Pathog 2014; 10:e1003843. [PMID: 24391499 PMCID: PMC3879355 DOI: 10.1371/journal.ppat.1003843] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 11/05/2013] [Indexed: 01/28/2023] Open
Abstract
The homeostatic mechanisms that regulate the maintenance of immunological memory to the multiple pathogen encounters over time are unknown. We found that a single malaria episode caused significant dysregulation of pre-established Influenza A virus-specific long-lived plasma cells (LLPCs) resulting in the loss of Influenza A virus-specific Abs and increased susceptibility to Influenza A virus re-infection. This loss of LLPCs involved an FcγRIIB-dependent mechanism, leading to their apoptosis. However, given enough time following malaria, the LLPC pool and humoral immunity to Influenza A virus were eventually restored. Supporting a role for continuous conversion of Influenza A virus-specific B into LLPCs in the restoration of Influenza A virus immunity, B cell depletion experiments also demonstrated a similar requirement for the long-term maintenance of serum Influenza A virus-specific Abs in an intact LLPC compartment. These findings show that, in addition to their established role in the anamnestic response to reinfection, the B cell pool continues to be a major contributor to the maintenance of long-term humoral immunity following primary Influenza A virus infection, and to the recovery from attrition following heterologous infection. These data have implications for understanding the longevity of protective efficacy of vaccinations in countries where continuous infections are endemic. Antibody responses to infectious pathogens are critical in host survival, recovery and protection from reinfection; they also correlate with the success of vaccination. It is currently thought that antibody serum titers are maintained at protective levels over long periods of time by specialized long-lived antibody-secreting plasma cells residing in the bone marrow. Indeed, antibodies against the original virus can still be found in survivors of the 1918 Spanish Flu, more than 90 years ago. However, it is also becoming clear that subsequent infection with heterologous pathogens may cause attrition of previously established immunological memory, in order to accommodate new lymphocyte specificities in the finite space of the host. This phenomenon is seemingly at odds with long-term maintenance of immunological memory. We also show that a single episode of malaria, caused by infection by Plasmodium chabaudi, leads to the loss of preexisting plasma cells, serum antibodies and protective immunity against Influenza A virus. However, Influenza A virus-specific immunity does eventually recover in these animals with the replenishment of plasma cells by B cells over the course of several weeks. Thus, the reported mechanism reconciles attrition of immunological memory by heterologous infection and long-term stability, and places B cells, instead of their descendant plasma cells, at the center of humoral memory.
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Affiliation(s)
- Dorothy H. L. Ng
- Division of Immunoregulation, MRC National Institute for Medical Research, London, United Kingdom
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - John J. Skehel
- Division of Virology, MRC National Institute for Medical Research, London, United Kingdom
| | - George Kassiotis
- Division of Immunoregulation, MRC National Institute for Medical Research, London, United Kingdom
- * E-mail: (GK); (JL)
| | - Jean Langhorne
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
- * E-mail: (GK); (JL)
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16
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Kim CC, Nelson CS, Wilson EB, Hou B, DeFranco AL, DeRisi JL. Splenic red pulp macrophages produce type I interferons as early sentinels of malaria infection but are dispensable for control. PLoS One 2012; 7:e48126. [PMID: 23144737 PMCID: PMC3483282 DOI: 10.1371/journal.pone.0048126] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 09/27/2012] [Indexed: 01/19/2023] Open
Abstract
Type I interferons (T1IFNs) are among the earliest cytokines produced during infections due to their direct regulation by innate immune signaling pathways. Reports have suggested that T1IFNs are produced during malaria infection, but little is known about the in vivo cellular origins of T1IFNs or their role in protection. We have found that in addition to plasmacytoid dendritic cells, splenic red pulp macrophages (RPMs) can generate significant quantities of T1IFNs in response to P. chabaudi infection in a TLR9-, MYD88-, and IRF7-dependent manner. Furthermore, T1IFNs regulate expression of interferon-stimulated genes redundantly with Interferon-gamma (IFNG), resulting in redundancy for resistance to experimental malaria infection. Despite their role in sensing and promoting immune responses to infection, we observe that RPMs are dispensable for control of parasitemia. Our results reveal that RPMs are early sentinels of malaria infection, but that effector mechanisms previously attributed to RPMs are not essential for control.
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Affiliation(s)
- Charles C Kim
- Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
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17
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Biswas S, Spencer AJ, Forbes EK, Gilbert SC, Holder AA, Hill AVS, Draper SJ. Recombinant viral-vectored vaccines expressing Plasmodium chabaudi AS apical membrane antigen 1: mechanisms of vaccine-induced blood-stage protection. J Immunol 2012; 188:5041-53. [PMID: 22504652 PMCID: PMC3378655 DOI: 10.4049/jimmunol.1101106] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Apical membrane Ag 1 (AMA1) is one of the leading candidate Ags for inclusion in a subunit vaccine against blood-stage malaria. However, the efficacy of Ab-inducing recombinant AMA1 protein vaccines in phase IIa/b clinical trials remains disappointing. In this article, we describe the development of recombinant human adenovirus serotype 5 and modified vaccinia virus Ankara vectors encoding AMA1 from the Plasmodium chabaudi chabaudi strain AS. These vectors, when used in a heterologous prime-boost regimen in BALB/c mice, are capable of inducing strong transgene-specific humoral and cellular immune responses. We show that this vaccination regimen is protective against a nonlethal P. chabaudi chabaudi strain AS blood-stage challenge, resulting in reduced peak parasitemias. The role of vaccine-induced, AMA1-specific Abs and T cells in mediating the antiparasite effect was investigated by in vivo depletion of CD4(+) T cells and adoptive-transfer studies into naive and immunodeficient mice. Depletion of CD4(+) T cells led to a loss of vaccine-induced protection. Adoptive-transfer studies confirmed that efficacy is mediated by both CD4(+) T cells and Abs functioning in the context of an intact immune system. Unlike previous studies, these results confirm that Ag-specific CD4(+) T cells, induced by a clinically relevant vaccine-delivery platform, can make a significant contribution to vaccine blood-stage efficacy in the P. chabaudi model. Given that cell-mediated immunity may also contribute to parasite control in human malaria, these data support the clinical development of viral-vectored vaccines that induce both T cell and Abs against Plasmodium falciparum blood-stage malaria Ags like AMA1.
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MESH Headings
- Adenoviruses, Human/genetics
- Adenoviruses, Human/immunology
- Animals
- Antibodies, Protozoan/biosynthesis
- Antibodies, Protozoan/blood
- Antibodies, Viral/biosynthesis
- Antibodies, Viral/blood
- Antigens, Protozoan/blood
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Female
- Genetic Vectors/administration & dosage
- Genetic Vectors/immunology
- Humans
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/genetics
- Malaria Vaccines/immunology
- Malaria, Falciparum/blood
- Malaria, Falciparum/immunology
- Malaria, Falciparum/prevention & control
- Membrane Proteins/blood
- Membrane Proteins/genetics
- Membrane Proteins/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Mice, Nude
- Molecular Sequence Data
- Plasmodium chabaudi/genetics
- Plasmodium chabaudi/immunology
- Plasmodium falciparum/genetics
- Plasmodium falciparum/immunology
- Protozoan Proteins/blood
- Protozoan Proteins/genetics
- Protozoan Proteins/immunology
- Vaccines, Subunit/administration & dosage
- Vaccines, Subunit/genetics
- Vaccines, Subunit/immunology
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Vaccinia virus/genetics
- Vaccinia virus/immunology
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Affiliation(s)
- Sumi Biswas
- Jenner Institute, University of Oxford, Oxford OX3 7DQ, United Kingdom.
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18
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Zago CA, Bortoluci KR, Sardinha LR, Pretel FD, Castillo-Méndez SI, Freitas do Rosário AP, Hiyane MI, Muxel SM, Rodriguez-Málaga SM, Abrahamsohn IA, Álvarez JM, D'Império Lima MR. Anti-IL-2 treatment impairs the expansion of T(reg) cell population during acute malaria and enhances the Th1 cell response at the chronic disease. PLoS One 2012; 7:e29894. [PMID: 22272258 PMCID: PMC3260167 DOI: 10.1371/journal.pone.0029894] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 12/07/2011] [Indexed: 01/01/2023] Open
Abstract
Plasmodium chabaudi infection induces a rapid and intense splenic CD4(+) T cell response that contributes to both disease pathogenesis and the control of acute parasitemia. The subsequent development of clinical immunity to disease occurs concomitantly with the persistence of low levels of chronic parasitemia. The suppressive activity of regulatory T (T(reg)) cells has been implicated in both development of clinical immunity and parasite persistence. To evaluate whether IL-2 is required to induce and to sustain the suppressive activity of T(reg) cells in malaria, we examined in detail the effects of anti-IL-2 treatment with JES6-1 monoclonal antibody (mAb) on the splenic CD4(+) T cell response during acute and chronic P. chabaudi AS infection in C57BL/6 mice. JES6-1 treatment on days 0, 2 and 4 of infection partially inhibits the expansion of the CD4(+)CD25(+)Foxp3(+) cell population during acute malaria. Despite the concomitant secretion of IL-2 and expression of high affinity IL-2 receptor by large CD4(+) T cells, JES6-1 treatment does not impair effector CD4(+) T cell activation and IFN-γ production. However, at the chronic phase of the disease, an enhancement of cellular and humoral responses occurs in JES6-1-treated mice, with increased production of TNF-α and parasite-specific IgG2a antibodies. Furthermore, JES6-1 mAb completely blocked the in vitro proliferation of CD4(+) T cells from non-treated chronic mice, while it further increased the response of CD4(+) T cells from JES6-1-treated chronic mice. We conclude that JES6-1 treatment impairs the expansion of T(reg) cell population during early P. chabaudi malaria and enhances the Th1 cell response in the late phase of the disease.
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Affiliation(s)
- Cláudia A Zago
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brasil.
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19
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Tulone C, Sponaas AM, Raiber EA, Tabor AB, Langhorne J, Chain BM. Differential requirement for cathepsin D for processing of the full length and C-terminal fragment of the malaria antigen MSP1. PLoS One 2011; 6:e24886. [PMID: 22053177 PMCID: PMC3203867 DOI: 10.1371/journal.pone.0024886] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 08/23/2011] [Indexed: 11/19/2022] Open
Abstract
Merozoite Surface Protein 1 is expressed on the surface of malaria merozoites and is important for invasion of the malaria parasite into erythrocytes. MSP1-specific CD4 T cell responses and antibody can confer protective immunity in experimental models of malaria. In this study we explore the contributions of cathepsins D and E, two aspartic proteinases previously implicated in antigen processing, to generating MSP1 CD4 T-cell epitopes for presentation. The absence of cathepsin D, a late endosome/lysosomal enzyme, is associated with a reduced presentation of MSP1 both following in vitro processing of the epitope MSP1 from infected erythrocytes by bone marrow-derived dendritic cells, and following in vivo processing by splenic CD11c+ dendritic cells. By contrast, processing and presentation of the soluble recombinant protein fragment of MSP1 is unaffected by the absence of cathepsin D, but is inhibited when both cathepsin D and E are absent. The role of different proteinases in generating the CD4 T cell repertoire, therefore, depends on the context in which an antigen is introduced to the immune system.
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Affiliation(s)
- Calogero Tulone
- Division of Infection and Immunity, University College London, London, United Kingdom
| | - Anne-Marit Sponaas
- Division of Parasitology MRC National Institute of Medical Research, London, United Kingdom
| | - Eun-Ang Raiber
- Department of Chemistry, University College London, London, United Kingdom
| | - Alethea B. Tabor
- Department of Chemistry, University College London, London, United Kingdom
| | - Jean Langhorne
- Division of Parasitology MRC National Institute of Medical Research, London, United Kingdom
| | - Benny M. Chain
- Division of Infection and Immunity, University College London, London, United Kingdom
- * E-mail:
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20
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Weidanz WP, Lafleur G, Kita-Yarbro A, Nelson K, Burns JM. Signalling through the IL-2 receptor γ(c) peptide (CD132) is essential for the expression of immunity to Plasmodium chabaudi adami blood-stage malaria. Parasite Immunol 2011; 33:512-6. [PMID: 21585397 PMCID: PMC3155670 DOI: 10.1111/j.1365-3024.2011.01298.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A genetic dissection approach was employed to determine whether the IL-2 receptor complex (IL-2R) comprised of α, β and γ chains is required for the suppression of Plasmodium chabaudi adami parasitemia. Blood-stage infections in IL-2Rγ(c)(-/y) mice failed to cure with parasitemia remaining elevated for > 50 days indicating the IL-2Rγ(c) through which all members of the γ(c) family of cytokines signal has an essential role in protective immunity against blood-stage malarial parasites. In contrast, the curing of parasitemia in IL-2/15Rβ⁻/⁻ mice, deficient in both IL-2 and IL-15 signalling was significantly delayed but did occur, indicating that neither cytokine plays an essential role in parasite clearance. Moreover, the observation that the time course of parasitemia in IL-15⁻/⁻ mice was nearly identical to that seen in controls suggests that the parasitemia-suppressing role of stimulating through the IL-2/15Rβ chain is owing to IL-2 signalling and not a redundant function of IL-15.
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Affiliation(s)
- W P Weidanz
- Medical Microbiology and Immunology, University of Wisconsin, Madison, WI 53706, USA.
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21
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Delić D, Ellinger-Ziegelbauer H, Vohr HW, Dkhil M, Al-Quraishy S, Wunderlich F. Testosterone response of hepatic gene expression in female mice having acquired testosterone-unresponsive immunity to Plasmodium chabaudi malaria. Steroids 2011; 76:1204-12. [PMID: 21669218 DOI: 10.1016/j.steroids.2011.05.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 05/20/2011] [Accepted: 05/25/2011] [Indexed: 01/18/2023]
Abstract
Blood-stage malaria of Plasmodium chabaudi is characterized by its responsiveness to testosterone (T): T suppresses development of protective immunity, whereas once acquired immunity is T-unresponsive. Here, we have analyzed the liver, a T target and lymphoid organ with anti-malaria activity, for its T-responsiveness of gene expression in immune mice. Using Affymetrix microarray technology, in combination with quantitative RT-PCR, we have identified (i) T-unresponsive expression of newly acquired mRNAs encoding diverse sequences of IgG- and IgM-antibodies, (ii) 24 genes whose expression has become T-unresponsive including those encoding the T(H)2 response promoting EHMT2 and the erythrocyte membrane protein band 7.2 STOM, (iii) T-unresponsive expression of mRNAs for the cytokines IL-1β, IL-6, TNFα, and IFNγ, as well as iNOS, which are even not inducible by infection, and (iv) 35 genes retaining their T-responsiveness, which include those encoding the infection-inducible acute phase proteins SAA1, SAA2, and ORM2 as well as those of liver metabolism which encode the T-downregulated female-prevalent enzymes CYP2B9, CYP2B13, CYP3A41, CYP7A1, and SULT2A2 and the T-upregulated male-prevalent enzymes CYP2D9, CYP7B1, UGT2B1, HSD3B2, HSD3B5, respectively. The mRNA of the latter T-metabolizing enzyme is even 5-fold increased by T, suggesting a decrease in the effective T concentrations in the liver of immune mice. Collectively, our data suggest that the liver, which has acquired a selective T-unresponsiveness of gene expression, contributes to the acquired T-unresponsive, antibody-mediated protective immunity to blood-stage malaria of P. chabaudi.
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Affiliation(s)
- D Delić
- Division of Molecular Parasitology and Centre for Biological and Medical Research, Heinrich-Heine-University, Universitaetsstr. 1, 40225 Duesseldorf, Germany.
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22
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Muxel SM, Freitas do Rosário AP, Zago CA, Castillo-Méndez SI, Sardinha LR, Rodriguez-Málaga SM, Câmara NOS, Álvarez JM, Lima MRD. The spleen CD4+ T cell response to blood-stage Plasmodium chabaudi malaria develops in two phases characterized by different properties. PLoS One 2011; 6:e22434. [PMID: 21814579 PMCID: PMC3141041 DOI: 10.1371/journal.pone.0022434] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 06/28/2011] [Indexed: 11/19/2022] Open
Abstract
The pivotal role of spleen CD4+ T cells in the development of both malaria pathogenesis and protective immunity makes necessary a profound comprehension of the mechanisms involved in their activation and regulation during Plasmodium infection. Herein, we examined in detail the behaviour of non-conventional and conventional splenic CD4+ T cells during P. chabaudi malaria. We took advantage of the fact that a great proportion of CD4+ T cells generated in CD1d-/- mice are I-Ab-restricted (conventional cells), while their counterparts in I-Ab-/- mice are restricted by CD1d and other class IB major histocompatibility complex (MHC) molecules (non-conventional cells). We found that conventional CD4+ T cells are the main protagonists of the immune response to infection, which develops in two consecutive phases concomitant with acute and chronic parasitaemias. The early phase of the conventional CD4+ T cell response is intense and short lasting, rapidly providing large amounts of proinflammatory cytokines and helping follicular and marginal zone B cells to secrete polyclonal immunoglobulin. Both TNF-α and IFN-γ production depend mostly on conventional CD4+ T cells. IFN-γ is produced simultaneously by non-conventional and conventional CD4+ T cells. The early phase of the response finishes after a week of infection, with the elimination of a large proportion of CD4+ T cells, which then gives opportunity to the development of acquired immunity. Unexpectedly, the major contribution of CD1d-restricted CD4+ T cells occurs at the beginning of the second phase of the response, but not earlier, helping both IFN-γ and parasite-specific antibody production. We concluded that conventional CD4+ T cells have a central role from the onset of P. chabaudi malaria, acting in parallel with non-conventional CD4+ T cells as a link between innate and acquired immunity. This study contributes to the understanding of malaria immunology and opens a perspective for future studies designed to decipher the molecular mechanisms behind immune responses to Plasmodium infection.
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Affiliation(s)
- Sandra Marcia Muxel
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
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23
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Farias AS, Talaisys RL, Blanco YC, Lopes SCP, Longhini ALF, Pradella F, Santos LMB, Costa FTM. Regulatory T cell induction during Plasmodium chabaudi infection modifies the clinical course of experimental autoimmune encephalomyelitis. PLoS One 2011; 6:e17849. [PMID: 21464982 PMCID: PMC3064572 DOI: 10.1371/journal.pone.0017849] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 02/10/2011] [Indexed: 11/19/2022] Open
Abstract
Background Experimental autoimmune encephalomyelitis (EAE) is used as an animal model for human multiple sclerosis (MS), which is an inflammatory demyelinating autoimmune disease of the central nervous system characterized by activation of Th1 and/or Th17 cells. Human autoimmune diseases can be either exacerbated or suppressed by infectious agents. Recent studies have shown that regulatory T cells play a crucial role in the escape mechanism of Plasmodium spp. both in humans and in experimental models. These cells suppress the Th1 response against the parasite and prevent its elimination. Regulatory T cells have been largely associated with protection or amelioration in several autoimmune diseases, mainly by their capacity to suppress proinflammatory response. Methodology/Principal Findings In this study, we verified that CD4+CD25+ regulatory T cells (T regs) generated during malaria infection (6 days after EAE induction) interfere with the evolution of EAE. We observed a positive correlation between the reduction of EAE clinical symptoms and an increase of parasitemia levels. Suppression of the disease was also accompanied by a decrease in the expression of IL-17 and IFN-γ and increases in the expression of IL-10 and TGF-β1 relative to EAE control mice. The adoptive transfer of CD4+CD25+ cells from P. chabaudi-infected mice reduced the clinical evolution of EAE, confirming the role of these T regs. Conclusions/Significance These data corroborate previous findings showing that infections interfere with the prevalence and evolution of autoimmune diseases by inducing regulatory T cells, which regulate EAE in an apparently non-specific manner.
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MESH Headings
- Animals
- Autoimmunity/immunology
- Cell Survival
- Cytokines/genetics
- Cytokines/metabolism
- Disease Progression
- Encephalomyelitis, Autoimmune, Experimental/complications
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/parasitology
- Gene Expression Regulation
- Humans
- Interleukin-2 Receptor alpha Subunit/metabolism
- Malaria/complications
- Malaria/genetics
- Malaria/immunology
- Malaria/parasitology
- Mice
- Mice, Inbred C57BL
- Plasmodium chabaudi/immunology
- T-Lymphocytes, Regulatory/immunology
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Affiliation(s)
- Alessandro S. Farias
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
- * E-mail: (ASF); (FTMC)
| | - Rafael L. Talaisys
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Yara C. Blanco
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Stefanie C. P. Lopes
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Ana Leda F. Longhini
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Fernando Pradella
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Leonilda M. B. Santos
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Fabio T. M. Costa
- Departmento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
- * E-mail: (ASF); (FTMC)
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24
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Nduati EW, Ng DHL, Ndungu FM, Gardner P, Urban BC, Langhorne J. Distinct kinetics of memory B-cell and plasma-cell responses in peripheral blood following a blood-stage Plasmodium chabaudi infection in mice. PLoS One 2010; 5:e15007. [PMID: 21124900 PMCID: PMC2990717 DOI: 10.1371/journal.pone.0015007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 10/04/2010] [Indexed: 12/25/2022] Open
Abstract
B cell and plasma cell responses take place in lymphoid organs, but because of the inaccessibility of these organs, analyses of human responses are largely performed using peripheral blood mononuclear cells (PBMC). To determine whether PBMC are a useful source of memory B cells and plasma cells in malaria, and whether they reflect Plasmodium-specific B cell responses in spleen or bone marrow, we have investigated these components of the humoral response in PBMC using a model of Plasmodium chabaudi blood-stage infections in C57BL/6 mice. We detected memory B cells, defined as isotype-switched IgD− IgM− CD19+ B cells, and low numbers of Plasmodium chabaudi Merozoite Surface Protein-1 (MSP1)-specific memory B cells, in PBMC at all time points sampled for up to 90 days following primary or secondary infection. By contrast, we only detected CD138+ plasma cells and MSP1-specific antibody-secreting cells within a narrow time frame following primary (days 10 to 25) or secondary (day 10) infection. CD138+ plasma cells in PBMC at these times expressed CD19, B220 and MHC class II, suggesting that they were not dislodged bone-marrow long-lived plasma cells, but newly differentiated migratory plasmablasts migrating to the bone marrow; thus reflective of an ongoing or developing immune response. Our data indicates that PBMC can be a useful source for malaria-specific memory B cells and plasma cells, but extrapolation of the results to human malaria infections suggests that timing of sampling, particularly for plasma cells, may be critical. Studies should therefore include multiple sampling points, and at times of infection/immunisation when the B-cell phenotypes of interest are likely to be found in peripheral blood.
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Affiliation(s)
- Eunice W. Nduati
- KEMRI/Wellcome Trust Collaborative Research Programme, Centre for Geographical Medicine Research Coast, Kilifi, Kenya
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Dorothy H. L. Ng
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Francis M. Ndungu
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Peter Gardner
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Britta C. Urban
- KEMRI/Wellcome Trust Collaborative Research Programme, Centre for Geographical Medicine Research Coast, Kilifi, Kenya
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jean Langhorne
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
- * E-mail:
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25
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Miller MR, Råberg L, Read AF, Savill NJ. Quantitative analysis of immune response and erythropoiesis during rodent malarial infection. PLoS Comput Biol 2010; 6:e1000946. [PMID: 20941388 PMCID: PMC2947982 DOI: 10.1371/journal.pcbi.1000946] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2010] [Accepted: 08/31/2010] [Indexed: 12/20/2022] Open
Abstract
Malarial infection is associated with complex immune and erythropoietic responses in the host. A quantitative understanding of these processes is essential to help inform malaria therapy and for the design of effective vaccines. In this study, we use a statistical model-fitting approach to investigate the immune and erythropoietic responses in Plasmodium chabaudi infections of mice. Three mouse phenotypes (wildtype, T-cell-deficient nude mice, and nude mice reconstituted with T-cells taken from wildtype mice) were infected with one of two parasite clones (AS or AJ). Under a Bayesian framework, we use an adaptive population-based Markov chain Monte Carlo method and fit a set of dynamical models to observed data on parasite and red blood cell (RBC) densities. Model fits are compared using Bayes' factors and parameter estimates obtained. We consider three independent immune mechanisms: clearance of parasitised RBCs (pRBC), clearance of unparasitised RBCs (uRBC), and clearance of parasites that burst from RBCs (merozoites). Our results suggest that the immune response of wildtype mice is associated with less destruction of uRBCs, compared to the immune response of nude mice. There is a greater degree of synchronisation between pRBC and uRBC clearance than between either mechanism and merozoite clearance. In all three mouse phenotypes, control of the peak of parasite density is associated with pRBC clearance. In wildtype mice and AS-infected nude mice, control of the peak is also associated with uRBC clearance. Our results suggest that uRBC clearance, rather than RBC infection, is the major determinant of RBC dynamics from approximately day 12 post-innoculation. During the first 2-3 weeks of blood-stage infection, immune-mediated clearance of pRBCs and uRBCs appears to have a much stronger effect than immune-mediated merozoite clearance. Upregulation of erythropoiesis is dependent on mouse phenotype and is greater in wildtype and reconstitited mice. Our study highlights the informative power of statistically rigorous model-fitting techniques in elucidating biological systems.
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Affiliation(s)
- Martin R. Miller
- Centre for Infectious Diseases, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Lars Råberg
- Department of Animal Ecology, Lund University, Lund, Sweden
| | - Andrew F. Read
- Center for Infectious Disease Dynamics and Departments of Biology and Entomology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Nicholas J. Savill
- Centre for Infectious Diseases, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
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26
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Delić D, Warskulat U, Borsch E, Al-Qahtani S, Al-Quraishi S, Häussinger D, Wunderlich F. Loss of ability to self-heal malaria upon taurine transporter deletion. Infect Immun 2010; 78:1642-9. [PMID: 20100858 PMCID: PMC2849432 DOI: 10.1128/iai.01159-09] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Revised: 11/24/2009] [Accepted: 01/18/2010] [Indexed: 12/31/2022] Open
Abstract
Deletion of the taurine transporter gene (taut) results in lowered levels of taurine, the most abundant amino acid in mammals. Here, we show that taut-/- mice have lost their ability to self-heal blood-stage infections with Plasmodium chabaudi malaria. All taut-/- mice succumb to infections during crisis, while about 90% of the control taut(+/+) mice survive. The latter retain unchanged taurine levels even at peak parasitemia. Deletion of taut, however, results in the lowering of circulating taurine levels from 540 to 264 micromol/liter, and infections cause additional lowering to 192 micromol/liter. Peak parasitemia levels in taut-/- mice are approximately 60% higher than those in taut(+/+) mice, an elevation that is associated with increased systemic tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels, as well as with liver injuries. The latter manifest as increased systemic ammonia levels, a perturbed capacity to entrap injected particles, and increased expression of genes encoding TNF-alpha, IL-1beta, IL-6, inducible nitric oxide synthase (iNOS), NF-kappaB, and vitamin D receptor (VDR). Autopsy reveals multiorgan failure as the cause of death for malaria-infected taut-/- mice. Our data indicate that taut-controlled taurine homeostasis is essential for resistance to P. chabaudi malaria. Taurine deficiency due to taut deletion, however, impairs the eryptosis of P. chabaudi-parasitized erythrocytes and expedites increases in systemic TNF-alpha, IL-1beta, and ammonia levels, presumably contributing to multiorgan failure in P. chabaudi-infected taut-/- mice.
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Affiliation(s)
- Denis Delić
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
| | - Ulrich Warskulat
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
| | - Elena Borsch
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
| | - Saad Al-Qahtani
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
| | - Saleh Al-Quraishi
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
| | - Dieter Häussinger
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
| | - Frank Wunderlich
- Division of Molecular Parasitology, Department of Biology, and Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine- University, Universitätsstr. 1, Clinic for Gastroenterology, Hepatology, and Infectiology, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany, Teacher College, Zoology Department, College of Science, King Saud University, 11352 Riyadh, Saudi Arabia
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Fairlie-Clarke KJ, Lamb TJ, Langhorne J, Graham AL, Allen JE. Antibody isotype analysis of malaria-nematode co-infection: problems and solutions associated with cross-reactivity. BMC Immunol 2010; 11:6. [PMID: 20163714 PMCID: PMC2838755 DOI: 10.1186/1471-2172-11-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Accepted: 02/17/2010] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Antibody isotype responses can be useful as indicators of immune bias during infection. In studies of parasite co-infection however, interpretation of immune bias is complicated by the occurrence of cross-reactive antibodies. To confidently attribute shifts in immune bias to the presence of a co-infecting parasite, we suggest practical approaches to account for antibody cross-reactivity. The potential for cross-reactive antibodies to influence disease outcome is also discussed. RESULTS Utilising two murine models of malaria-helminth co-infection we analysed antibody responses of mice singly- or co-infected with Plasmodium chabaudi chabaudi and Nippostrongylus brasiliensis or Litomosoides sigmodontis. We observed cross-reactive antibody responses that recognised antigens from both pathogens irrespective of whether crude parasite antigen preparations or purified recombinant proteins were used in ELISA. These responses were not apparent in control mice. The relative strength of cross-reactive versus antigen-specific responses was determined by calculating antibody titre. In addition, we analysed antibody binding to periodate-treated antigens, to distinguish responses targeted to protein versus carbohydrate moieties. Periodate treatment affected both antigen-specific and cross-reactive responses. For example, malaria-induced cross-reactive IgG1 responses were found to target the carbohydrate component of the helminth antigen, as they were not detected following periodate treatment. Interestingly, periodate treatment of recombinant malaria antigen Merozoite Surface Protein-119 (MSP-119) resulted in increased detection of antigen-specific IgG2a responses in malaria-infected mice. This suggests that glycosylation may have been masking protein epitopes and that periodate-treated MSP-119 may more closely reflect the natural non-glycosylated antigen seen during infection. CONCLUSIONS In order to utilize antibody isotypes as a measure of immune bias during co-infection studies, it is important to dissect antigen-specific from cross-reactive antibody responses. Calculating antibody titre, rather than using a single dilution of serum, as a measure of the relative strength of the response, largely accomplished this. Elimination of the carbohydrate moiety of an antigen that can often be the target of cross-reactive antibodies also proved useful.
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Affiliation(s)
- Karen J Fairlie-Clarke
- Institutes of Evolution, Immunology and Infection Research, School of Biological Sciences, King's Buildings, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK
| | - Tracey J Lamb
- Current address: School of Biological Sciences, The University of Reading, Reading, Berks RG6 6UB, UK
| | - Jean Langhorne
- Division of Parasitology, National Institute for Medical Research, The Ridgeway Mill Hill, NW7 1AA, UK
| | - Andrea L Graham
- Institutes of Evolution, Immunology and Infection Research, School of Biological Sciences, King's Buildings, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - Judith E Allen
- Institutes of Evolution, Immunology and Infection Research, School of Biological Sciences, King's Buildings, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK
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28
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Ndungu FM, Cadman ET, Coulcher J, Nduati E, Couper E, MacDonald DW, Ng D, Langhorne J. Functional memory B cells and long-lived plasma cells are generated after a single Plasmodium chabaudi infection in mice. PLoS Pathog 2009; 5:e1000690. [PMID: 20011127 PMCID: PMC2784955 DOI: 10.1371/journal.ppat.1000690] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Accepted: 11/11/2009] [Indexed: 11/18/2022] Open
Abstract
Antibodies have long been shown to play a critical role in naturally acquired immunity to malaria, but it has been suggested that Plasmodium-specific antibodies in humans may not be long lived. The cellular mechanisms underlying B cell and antibody responses are difficult to study in human infections; therefore, we have investigated the kinetics, duration and characteristics of the Plasmodium-specific memory B cell response in an infection of P. chabaudi in mice. Memory B cells and plasma cells specific for the C-terminal region of Merozoite Surface Protein 1 were detectable for more than eight months following primary infection. Furthermore, a classical memory response comprised predominantly of the T-cell dependent isotypes IgG2c, IgG2b and IgG1 was elicited upon rechallenge with the homologous parasite, confirming the generation of functional memory B cells. Using cyclophosphamide treatment to discriminate between long-lived and short-lived plasma cells, we demonstrated long-lived cells secreting Plasmodium-specific IgG in both bone marrow and in spleens of infected mice. The presence of these long-lived cells was independent of the presence of chronic infection, as removal of parasites with anti-malarial drugs had no impact on their numbers. Thus, in this model of malaria, both functional Plasmodium-specific memory B cells and long-lived plasma cells can be generated, suggesting that defects in generating these cell populations may not be the reason for generating short-lived antibody responses. Malaria causes considerable human suffering resulting from associated high mortality, morbidity and reduced economic productivity in endemic areas. Current control methods are thwarted by a multiplicity of problems including rapidly developing resistance for anti-malarial drugs and insecticide-treated nets, and huge costs and hence poor coverage with bed nets in poor countries. Understanding the basis of the inefficiency of immunity to malaria in childhood will greatly aid the search for effective vaccines, which together with drugs and vector control, will be essential in the drive to eliminate malaria. Because of the strong evidence associating anti-malarial antibodies with anti-parasitic and anti-disease effects, vaccines inducing protective long-lasting antibody responses are attractive. However, it has been suggested that antibody responses to some Plasmodium antigens may be not long-lived. It would be important to determine whether long-lived plasma cells and memory B cells are generated after a malaria infection; however, these studies are difficult to perform in humans. Therefore we investigated the kinetics, duration and characteristics of the two cell types responsible for long-term antibody production in a mouse model of malaria. We show here that malaria-specific memory B cells and plasma cells are still detectable more than eight months after infection, and that both long-lived malaria-specific antibody-secreting cells and functional malaria-specific memory B cells can be made after a single infection.
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Affiliation(s)
- Francis Maina Ndungu
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Emma Tamsin Cadman
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Joshua Coulcher
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Eunice Nduati
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | - Elisabeth Couper
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | | | - Dorothy Ng
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Jean Langhorne
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
- * E-mail:
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29
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Barclay VC, Chan BHK, Anders RF, Read AF. Mixed allele malaria vaccines: host protection and within-host selection. Vaccine 2008; 26:6099-107. [PMID: 18804509 PMCID: PMC2674600 DOI: 10.1016/j.vaccine.2008.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 09/01/2008] [Accepted: 09/01/2008] [Indexed: 11/19/2022]
Abstract
Malaria parasites are frequently polymorphic at the antigenic targets of many candidate vaccines, presumably as a consequence of selection pressure from protective immune responses. Conventional wisdom is therefore that vaccines directed against a single variant could select for non-target variants, rendering the vaccine useless. Many people have argued that a solution is to develop vaccines containing the products of more than one variant of the target. However, we are unaware of any evidence that multi-allele vaccines better protect hosts against parasites or morbidity. Moreover, selection of antigen-variants is not the only evolution that could occur in response to vaccination. Increased virulence could also be favored if more aggressive strains are less well controlled by vaccine-induced immunity. Virulence and antigenic identity have been confounded in all studies so far, and so we do not know formally from any animal or human studies whether vaccine failure has been due to evasion of protective responses by variants at target epitopes, or whether vaccines are just less good at protecting against more aggressive strains. Using the rodent malaria model Plasmodium chabaudi and recombinant apical membrane antigen-1 (AMA-1), we tested whether a bi-allelic vaccine afforded greater protection from parasite infection and morbidity than did vaccination with the component alleles alone. We also tested the effect of mono- and bi-allelic vaccination on within-host selection of mixed P. chabaudi infections, and whether parasite virulence mediates pathogen titres in immunized hosts. We found that vaccination with the bi-allelic AMA-1 formulation did not afford the host greater protection from parasite infection or morbidity than did mono-allelic AMA-1 immunization. Mono-allelic immunization increased the frequency of heterologous clones in mixed clone infections. There was no evidence that any type of immunization regime favored virulence. A single AMA-1 variant is a component of candidate malaria vaccines current in human trials; our results suggest that adding extra AMA-1 alleles to these vaccines would not confer clinical benefits, but that that mono-allelic vaccines could alter AMA-1 allele frequencies in natural populations.
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Achtman AH, Stephens R, Cadman ET, Harrison V, Langhorne J. Malaria-specific antibody responses and parasite persistence after infection of mice with Plasmodium chabaudi chabaudi. Parasite Immunol 2007; 29:435-44. [PMID: 17727567 DOI: 10.1111/j.1365-3024.2007.00960.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
While it is known that antibodies are critical for clearance of malaria infections, it is not clear whether adequate antibody responses are maintained and what effect chronic infection has on this response. Here we show that mice with low-grade chronic primary infections of Plasmodium chabaudi or infections very recently eliminated have reduced second infections when compared with the second infection of parasite-free mice. We also show that parasite-specific antibody responses induced by infection of mice with Plasmodium chabaudi contain both short- and long-lived components as well as memory B cells responsible for a faster antibody response during re-infection. Furthermore, parasite-specific antibodies to the C-terminal fragment of merozoite surface protein-1 (MSP-1) undergo avidity maturation. However, antibodies with both low and high avidity persist throughout infection and after re-infection, suggesting repeated rounds of activation and maturation of memory B cells. Neither the avidity profile of the antibody response, nor its maintenance is affected by persisting live parasites. Therefore, differences in parasitemia in re-infection cannot be explained solely by higher levels of antibody or greater affinity maturation of malaria-specific antibodies. These data suggest that there may be an antibody-independent component to the early control of secondary infections in mice that are chronically infected.
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Affiliation(s)
- A H Achtman
- Division of Parasitology, National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK
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31
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Millington OR, Gibson VB, Rush CM, Zinselmeyer BH, Phillips RS, Garside P, Brewer JM. Malaria impairs T cell clustering and immune priming despite normal signal 1 from dendritic cells. PLoS Pathog 2007; 3:1380-7. [PMID: 17937497 PMCID: PMC2014797 DOI: 10.1371/journal.ppat.0030143] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Accepted: 08/13/2007] [Indexed: 01/19/2023] Open
Abstract
Interactions between antigen-presenting dendritic cells (DCs) and T cells are essential for the induction of an immune response. However, during malaria infection, DC function is compromised and immune responses against parasite and heterologous antigens are reduced. Here, we demonstrate that malaria infection or the parasite pigment hemozoin inhibits T cell and DC interactions both in vitro and in vivo, while signal 1 intensity remains unaltered. This altered cellular behaviour is associated with the suppression of DC costimulatory activity and functional T cell responses, potentially explaining why immunity is reduced during malaria infection. Malaria is a major infectious disease, affecting 500 million people and causing 2.7 million deaths each year. The severity of malaria is, in part, due to the failure of the host immune system to effectively clear an infection and generate protective immunity. Dendritic cells (DCs) are central to the immune system; by presenting components of pathogens to circulating T cells, they are able to initiate a highly specific immune response to clear an infection. Importantly, the quality of the interaction between T cell and DCs can affect the functional outcome of the immune response. However, previous work has demonstrated that DCs are modified by malaria parasites, resulting in inefficient priming of the adaptive immune system. Here, we have visualised the interactions between DCs and T cells in the context of malaria and demonstrate that infection is able to prevent priming of immune responses by antagonising these cell–cell contacts. Importantly, the failure to form long-lasting interactions is not due to reduced presentation of antigens by the DC, suggesting that other mechanisms may be involved. These studies provide a visual insight into the mechanism by which parasites may suppress immunity and highlight the importance of early cellular interactions in the immune response.
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Affiliation(s)
- Owain R Millington
- Centre for Biophotonics, University of Strathclyde, Glasgow, United Kingdom
| | - Vivienne B Gibson
- Centre for Biophotonics, University of Strathclyde, Glasgow, United Kingdom
| | - Catherine M Rush
- Centre for Biophotonics, University of Strathclyde, Glasgow, United Kingdom
| | | | - R. Stephen Phillips
- Division of Infection and Immunity, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Paul Garside
- Centre for Biophotonics, University of Strathclyde, Glasgow, United Kingdom
| | - James M Brewer
- Centre for Biophotonics, University of Strathclyde, Glasgow, United Kingdom
- * To whom correspondence should be addressed. E-mail:
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32
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Wykes MN, Liu XQ, Jiang S, Hirunpetcharat C, Good MF. Systemic tumor necrosis factor generated during lethal Plasmodium infections impairs dendritic cell function. J Immunol 2007; 179:3982-7. [PMID: 17785836 DOI: 10.4049/jimmunol.179.6.3982] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Dendritic cells (DCs) initiate innate and adaptive immune responses including those against malaria. Although several studies have shown that DC function is normal during malaria, other studies have shown compromised function. To establish why these studies had different findings, we examined DCs from mice infected with two lethal species of parasite, Plasmodium berghei or P. vinckei, and compared them to DCs from nonlethal P. yoelii 17XNL or P. chabaudi infections. These studies found that DCs from only the lethal infections became uniformly mature 7 days after infection and were functionally impaired as they were unable to endocytose latex particles, secrete IL-12, or present OVA to transgenic OTII T cells. These changes coincided with a peak in levels of systemic TNF-alpha. Because TNF-alpha is known to mature DCs, we used TNF-KO mice to determine the role of this cytokine in the loss of DC function. In the TNF-KO mice, phenotype, Ag presentation, and IL-12 secretion by DCs were restored to normal following both lethal infections. This study shows that the systemic production of TNF-alpha contributes to poor DC function during lethal infections. These studies may explain, at least in part, immunosuppression that is associated with malaria.
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Affiliation(s)
- Michelle N Wykes
- The Molecular Immunology Laboratory, The Queensland Institute of Medical Research, The Bancroft Centre, Brisbane, Queensland, Australia
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33
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Turcotte K, Gauthier S, Malo D, Tam M, Stevenson MM, Gros P. Icsbp1/IRF-8 is required for innate and adaptive immune responses against intracellular pathogens. J Immunol 2007; 179:2467-76. [PMID: 17675508 DOI: 10.4049/jimmunol.179.4.2467] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The chronic myeloid leukemia syndrome of the BXH-2 mouse strain (Mus musculus) is caused by a recessive mutation (R294C) in the transcriptional regulator Icsbp1/IRF-8. In trans activation assays using an IL-12p40 gene reporter construct introduced in RAW 264.7 mouse macrophages, we show that the Icsbp1(C294) isoform behaves as a partial loss-of-function. The Icsbp1(C294) hypomorph allele appears to have a threshold effect on IL-12 production, with pleiotropic consequences on resistance to different types of infections in vivo. Despite the presence of a resistance Nramp1(G169) allele, BXH-2 mice (Icsbp1(C294)) show impaired control of Mycobacterium bovis (bacille Calmette-Guérin) multiplication both early and late during infection, with uncontrolled replication linked to inability to form granulomas in infected liver and spleen. Studies in informative (BXH-2 x BALB/cJ)F(2) mice show that homozygosity for Icsbp1(C294) causes susceptibility to Salmonella enterica serovar Typhimurium to a level comparable to that seen for mice lacking functional Nramp1 or TLR4. Finally, impaired Icsbp1(C294) function is associated with the following: 1) increased replication of the Plasmodium chabaudi AS malarial parasite during the first burst of blood parasitemia, and 2) recurring waves of high blood parasitemia late during infection. These results show that Icsbp1 is required for orchestrating early innate responses and also long-term immune protection against unrelated intracellular pathogens.
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MESH Headings
- Amino Acid Substitution
- Animals
- Cation Transport Proteins/genetics
- Cation Transport Proteins/immunology
- Cell Line
- Genes, Recessive
- Immunity, Innate/genetics
- Interferon Regulatory Factors/genetics
- Interferon Regulatory Factors/immunology
- Interleukin-12 Subunit p40/immunology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/immunology
- Macrophages/immunology
- Macrophages/microbiology
- Macrophages/parasitology
- Malaria/genetics
- Malaria/immunology
- Malaria/veterinary
- Mice
- Mice, Inbred BALB C
- Mice, Mutant Strains
- Mutation, Missense
- Mycobacterium bovis/immunology
- Parasitemia/genetics
- Parasitemia/immunology
- Plasmodium chabaudi/immunology
- Salmonella Infections/genetics
- Salmonella Infections/immunology
- Salmonella typhimurium/immunology
- Syndrome
- Toll-Like Receptor 4/genetics
- Toll-Like Receptor 4/immunology
- Tuberculosis/genetics
- Tuberculosis/immunology
- Tuberculosis/veterinary
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Affiliation(s)
- Karine Turcotte
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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Castillo-Méndez SI, Zago CA, Sardinha LR, Freitas do Rosário AP, Alvarez JM, D'Império Lima MR. Characterization of the spleen B-cell compartment at the early and late blood-stage Plasmodium chabaudi malaria. Scand J Immunol 2007; 66:309-19. [PMID: 17635808 DOI: 10.1111/j.1365-3083.2007.01972.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Polyclonal B-cell activation is a feature of the early spleen cell response to blood-stage Plasmodium chabaudi malaria. Immunity to blood-stage malaria is guaranteed by the generation of B cells able to produce parasite-specific antibodies mainly from the immunoglobulin (Ig)G2a isotype. In the present study, we characterized the spleen B-cell compartment during blood-stage P. chabaudi infection. The numbers of B220(+) and B220(LOW) CD138(+) (plasma) cells increased sharply between days 4 and 7 post-infection (p.i.). At this time B220(+) cells expressed surface (s)IgM, but nearly all B220(LOW) CD138(+) cells showed concomitantly intracellular (i)IgM and IgG2a. Both follicular and marginal zone B cells were activated expressing high amounts of CD69. At day 40 p.i., B220(LOW) CD138(+) cell population was still increased but, differently from acute infection, 61.1% of these cells were positive for iIgG2a while only 14.2% expressed iIgM. Moreover, at days 20 and 40 p.i., 29.2% and 13.0% of B220(+) cells expressed sIgG2a, respectively. According to cell size and expression of CD80, CD86, CD11b, CD44 and CD38, B220(+) sIgG2a(+) cells had a phenotype characteristic of activated/memory B cells. Furthermore, 14.1% of B220(+) sIgG2a(+) cells at day 30 p.i. expressed a marginal zone B-cell phenotype. Importantly, B cells from 40-day-infected mice were very efficient in presenting parasite antigens leading to proliferation of both CD4(+) and CD8(+) cells. Our results contribute for understanding the dynamics of B cells during P. chabaudi infection, underlying the mechanisms of antigen presentation and antibody production, which are essential for the acquisition of protective immunity against malaria.
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Affiliation(s)
- S I Castillo-Méndez
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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35
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Pattaradilokrat S, Cheesman SJ, Carter R. Linkage group selection: towards identifying genes controlling strain specific protective immunity in malaria. PLoS One 2007; 2:e857. [PMID: 17848988 PMCID: PMC1959240 DOI: 10.1371/journal.pone.0000857] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Accepted: 08/10/2007] [Indexed: 12/03/2022] Open
Abstract
Protective immunity against blood infections of malaria is partly specific to the genotype, or strain, of the parasites. The target antigens of Strain Specific Protective Immunity are expected, therefore, to be antigenically and genetically distinct in different lines of parasite. Here we describe the use of a genetic approach, Linkage Group Selection, to locate the target(s) of Strain Specific Protective Immunity in the rodent malaria parasite Plasmodium chabaudi chabaudi. In a previous such analysis using the progeny of a genetic cross between P. c. chabaudi lines AS-pyr1 and CB, a location on P. c. chabaudi chromosome 8 containing the gene for merozoite surface protein-1, a known candidate antigen for Strain Specific Protective Immunity, was strongly selected. P. c. chabaudi apical membrane antigen-1, another candidate for Strain Specific Protective Immunity, could not have been evaluated in this cross as AS-pyr1 and CB are identical within the cell surface domain of this protein. Here we use Linkage Group Selection analysis of Strain Specific Protective Immunity in a cross between P. c. chabaudi lines CB-pyr10 and AJ, in which merozoite surface protein-1 and apical membrane antigen-1 are both genetically distinct. In this analysis strain specific immune selection acted strongly on the region of P. c. chabaudi chromosome 8 encoding merozoite surface protein-1 and, less strongly, on the P. c. chabaudi chromosome 9 region encoding apical membrane antigen-1. The evidence from these two independent studies indicates that Strain Specific Protective Immunity in P. c. chabaudi in mice is mainly determined by a narrow region of the P. c. chabaudi genome containing the gene for the P. c. chabaudi merozoite surface protein-1 protein. Other regions, including that containing the gene for P. c. chabaudi apical membrane antigen-1, may be more weakly associated with Strain Specific Protective Immunity in these parasites.
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Affiliation(s)
- Sittiporn Pattaradilokrat
- Ashworth Laboratories, Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Sandra J. Cheesman
- Ashworth Laboratories, Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Richard Carter
- Ashworth Laboratories, Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- * To whom correspondence should be addressed. E-mail:
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van der Heyde HC, Burns JM, Weidanz WP, Horn J, Gramaglia I, Nolan JP. Analysis of antigen-specific antibodies and their isotypes in experimental malaria. Cytometry A 2007; 71:242-50. [PMID: 17252581 DOI: 10.1002/cyto.a.20377] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Measuring antibody production in response to antigen exposure or vaccination is key to disease prevention and treatment. Our understanding of the mechanisms involved in the antibody response is limited by a lack of sensitive analysis methods. We address this limitation using multiplexed microsphere arrays for the semi -quantitative analysis of antibody production in response to malaria infection. METHODS We used microspheres as solid supports on which to capture and analyze circulating antibodies. Antigen immobilized on beads captured antigen-specific antibodies for semi- quantitative analysis using fluorescent secondary antibodies. Anti-immunoglobulin antibodies on beads captured specific antibody isotypes for affinity estimation using fluorescent antigen. RESULTS Antigen-mediated capture of plasma antibodies enables determination of antigen-specific antibody "titer," a semi-quantitative parameter describing a convolution of antibody abundance and avidity, as well as parameters describing numbers of antibodies bound/bead at saturation and the plasma concentration-dependent approach to saturation. Results were identical in single-plex and multiplex assays, and in qualitative agreement with similar parameters derived from ELISA-based assays. Isotype-specific antibody-mediated capture of plasma antibodies allowed the estimation of the affinity of antibody for antigen. CONCLUSION Analysis of antibody responses using microspheres and flow cytometry offer significant advantages in speed, sample size, and quantification over standard ELISA-based titer methods.
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Patel SN, Lu Z, Ayi K, Serghides L, Gowda DC, Kain KC. Disruption of CD36 impairs cytokine response to Plasmodium falciparum glycosylphosphatidylinositol and confers susceptibility to severe and fatal malaria in vivo. J Immunol 2007; 178:3954-61. [PMID: 17339496 DOI: 10.4049/jimmunol.178.6.3954] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
CD36 is a scavenger receptor that has been implicated in malaria pathogenesis as well as innate defense against blood-stage infection. Inflammatory responses to Plasmodium falciparum GPI (pfGPI) anchors are believed to play an important role in innate immune response to malaria. We investigated the role of CD36 in pfGPI-induced MAPK activation and proinflammatory cytokine secretion. Furthermore, we explored the role of this receptor in an experimental model of acute malaria in vivo. We demonstrate that ERK1/2, JNK, p38, and c-Jun became phosphorylated in pfGPI-stimulated macrophages. In contrast, pfGPI-induced phosphorylation of JNK, ERK1/2, and c-Jun was reduced in Cd36(-/-) macrophages and Cd36(-/-) macrophages secreted significantly less TNF-alpha in response to pfGPI than their wild-type counterparts. In addition, we demonstrate a role for CD36 in innate immune response to malaria in vivo. Compared with wild-type mice, Cd36(-/-) mice experienced more severe and fatal malaria when challenged with Plasmodium chabaudi chabaudi AS. Cd36(-/-) mice displayed a combined defect in cytokine induction and parasite clearance with a dysregulated cytokine response to infection, earlier peak parasitemias, higher parasite densities, and higher mortality rates than wild-type mice. These results provide direct evidence that pfGPI induces TNF-alpha secretion in a CD36-dependent manner and support a role for CD36 in modulating host cytokine response and innate control of acute blood-stage malaria infection in vivo.
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Affiliation(s)
- Samir N Patel
- McLaughlin-Rotman Centre, University Health Network-Toronto General Hospital, McLaughlin Centre for Molecular Medicine, University of Toronto, 200 Elizabeth Street, Toronto, Ontario, Canada
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Min-Oo G, Tam M, Stevenson MM, Gros P. Pyruvate kinase deficiency: correlation between enzyme activity, extent of hemolytic anemia and protection against malaria in independent mouse mutants. Blood Cells Mol Dis 2007; 39:63-9. [PMID: 17466543 DOI: 10.1016/j.bcmd.2007.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 03/15/2007] [Accepted: 03/16/2007] [Indexed: 11/26/2022]
Abstract
AcB55, AcB61 and CBA/N-Pk(slc) mice carry loss of function mutations in the erythrocyte specific pyruvate kinase gene (Pklr). In AcB55 and AcB61 (Pklr(I90N)) PK deficiency is protective against blood-stage malaria. The mechanistic basis of protection against malaria is unknown and was studied in these two mutant alleles in vivo. The Pklr(G338D) mutation of the CBA/N-Pk(slc) mutant is shown to be more deleterious than the Pklr(I90N) allele with respect to enzymatic activity and severity of hemolytic anemia, with a more dramatic reduction in the half-life of erythrocytes (increased turnover) in the CBA/N-Pk(slc) mice. The CBA/N-Pk(slc) mice are also shown to be highly resistant to infection with Plasmodium chabaudi AS when compared to CBA/J and CBA/N controls. Resistance to malaria, measured as lower levels of blood-stage replication of P. chabaudi, rapid elimination of infected erythrocytes and increased survival to infection, was greater in the Pklr(G338D) mutant, CBA/N-Pk(slc), than in the Pklr(I90N) mutant strains, AcB55/AcB61. These results strongly suggest a correlation between severity of PK-deficiency and extent of protection against malaria. Additionally, the protective effect is independent of the genetic background on which the Pklr mutations occurred.
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Affiliation(s)
- Gundula Min-Oo
- Department of Biochemistry, McGill University, Montreal, Canada
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Clark K, Kulk N, Amante F, Haque A, Engwerda C. Lymphotoxin alpha and tumour necrosis factor are not required for control of parasite growth, but differentially regulate cytokine production during Plasmodium chabaudi chabaudi AS infection. Parasite Immunol 2007; 29:153-8. [PMID: 17266742 DOI: 10.1111/j.1365-3024.2006.00930.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Tumour necrosis factor (TNF) plays important roles in the pathogenesis of severe malaria, as well as in the generation of immune responses against malaria parasites. However, far less is known about the role of the closely related TNF family member lymphotoxin alpha (LTalpha) during malaria. We have used mice deficient in either TNF or LTalpha, as well as chimeric mice generated using donor bone marrow from these animals, to study the roles of these cytokines following Plasmodium chabaudi chabaudi AS infection. TNF and LTalpha were not required for the resolution of P. chabaudi chabaudi AS blood-stage infection. However, LTalpha, but not TNF, was necessary for early IFNgamma production and the regulation of IFNgamma production later in infection. A similar delay to that found for IFNgamma production was also observed for TNF production in LTalpha-deficient mice, compared with control mice. These results identify divergent roles for TNF and LTalpha in the regulation of host immune responses during P. chabaudi chabaudi AS infection.
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Affiliation(s)
- K Clark
- Immunology and Infection Laboratory, Queensland Institute of Medical Research, Herston, QLD, Australia
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40
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Franklin BS, Rodrigues SO, Antonelli LR, Oliveira RV, Goncalves AM, Sales-Junior PA, Valente EP, Alvarez-Leite JI, Ropert C, Golenbock DT, Gazzinelli RT. MyD88-dependent activation of dendritic cells and CD4(+) T lymphocytes mediates symptoms, but is not required for the immunological control of parasites during rodent malaria. Microbes Infect 2007; 9:881-90. [PMID: 17537666 DOI: 10.1016/j.micinf.2007.03.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 03/10/2007] [Accepted: 03/12/2007] [Indexed: 12/14/2022]
Abstract
We investigated the role of different TLRs and MyD88 in host resistance to infection and malaria pathogenesis. TLR2(-/-), TLR4(-/-), TLR6(-/-), TLR9(-/-) or CD14(-/-) mice showed no change in phenotypes (parasitemia, body weight and temperature) when infected with Plasmodium chabaudi chabaudi (AS). MyD88(-/-) mice displayed comparable ability to wild type animals in controlling and clearing parasitemia. Importantly, MyD88(-/-) mice exhibited impaired production of TNF-alpha and IFN-gamma as well as attenuated symptoms, as indicated by changes in body weight and temperature during parasitemia. Consistently, CD11b(+) monocytes and CD11c(+) dendritic cells from infected MyD88(-/-) mice were shown impaired for production of pro-inflammatory cytokines, and in initiating CD4(+) T cell responses. Importantly, the inhibition of T cell activation with anti-CD134L, mostly inhibited IFN-gamma, partially inhibited TNF-alpha production, and protected the animals from malaria symptoms. Our findings suggest that MyD88 and possibly its associated TLRs expressed by dendritic cells play an important role in pro-inflammatory responses, T cell activation, and pathogenesis of malaria, but are not critical for the immunological control of the erythrocytic stage of P. chabaudi.
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Martínez-Gómez F, Ixta-Rodríguez O, Aguilar-Figueroa B, Hernández-Cruz R, Monroy-Ostria A. Lactobaciilus casei ssp. rhamnosus enhances non specific protection against Plasmodium chabaudi AS in mice. Salud Publica Mex 2007; 48:498-503. [PMID: 17326346 DOI: 10.1590/s0036-36342006000600008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE To evaluate the capacity of Lactobacillus casei ssp. rhamnosus to enhance resistance against Plasmodium chabaudi chabaudi AS. MATERIAL AND METHODS NIH mice were IP injected with viable lactobacillus casei seven days (LC1 group) or 7 and 14 days (LC2 group) before the challenge (day 0) with Plasmodium chabaudi parasitized red blood cells (pRBC). Control mice were inoculated with pRBC only. When parasitaemia was resolved, naive mice were injected with spleen cells from each group. The parasitaemia was measured. Nitric oxide (NO*) in serum was determined. RESULTS Mice from the LC1 group presented a reduction in parasitaemia, with a prepatent period of five days, parasitaemia lasted 11 days, and the peak was (36.3 % pRBC) on the 12th day post-infection. Mice from the LC2 group showed a prepatent period of five days, parasitaemia lasted eight days, and the peak (30 % pRBC) was of on the 11th day. In the control, the prepatent period was three days, the parasitaemia lasted 15 days, and the peak (51% pRBC) was on day nine. Mice inoculated with spleen cells from the LC2 group showed a prepatent period of 21 days, parasitaemia lasted seven days, and the peak (13.5% pRBC) was on the 26th day. CONCLUSION L. casei enhanced nonspecific resistance to P. chabaudi, as indicated by longer prepatent periods, reduced parasitaemia, and reduction in the viability of the parasites recovered from the spleen of infected mice, along with high concentrations of NO* in serum.
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Affiliation(s)
- Federico Martínez-Gómez
- Departamento de Parasitología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional.
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42
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Min-Oo G, Fortin A, Pitari G, Tam M, Stevenson MM, Gros P. Complex genetic control of susceptibility to malaria: positional cloning of the Char9 locus. ACTA ACUST UNITED AC 2007; 204:511-24. [PMID: 17312006 PMCID: PMC2137903 DOI: 10.1084/jem.20061252] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mouse strains AcB55 and AcB61 are resistant to malaria by virtue of a mutation in erythrocyte pyruvate kinase (PklrI90N). Linkage analysis in [AcB55 × A/J] F2 mice detected a second locus (Char9; logarithm of odds = 4.74) that regulates the blood-stage replication of Plasmodium chabaudi AS independently of Pklr. We characterized the 77 genes of the Char9 locus for tissue-specific expression, strain-specific alterations in gene expression, and polymorphic variants that are possibly associated with differential susceptibility. We identified Vnn1/Vnn3 as the likely candidates responsible for Char9. Vnn3/Vnn1 map within a conserved haplotype block and show expression levels that are strictly cis-regulated by this haplotype. The absence of Vnn messenger RNA expression and lack of pantetheinase protein activity in tissues are associated with susceptibility to malaria and are linked to a complex rearrangement in the Vnn3 promoter region. The A/J strain also carries a unique nonsense mutation that leads to a truncated protein. Vanin genes code for a pantetheinase involved in the production of cysteamine, a key regulator of host responses to inflammatory stimuli. Administration of cystamine in vivo partially corrects susceptibility to malaria in A/J mice, as measured by reduced blood parasitemia and decreased mortality. These studies suggest that pantetheinase is critical for the host response to malaria.
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Affiliation(s)
- Gundula Min-Oo
- Department of Biochemistry, The Research Institute of McGill University Health Centre, McGill University, Montreal H3G-1Y6, Quebec, Canada
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43
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Beattie L, Engwerda CR, Wykes M, Good MF. CD8+ T lymphocyte-mediated loss of marginal metallophilic macrophages following infection with Plasmodium chabaudi chabaudi AS. J Immunol 2006; 177:2518-26. [PMID: 16888013 DOI: 10.4049/jimmunol.177.4.2518] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The splenic architecture is essential for the quick resolution of a primary infection with Plasmodium. A critical component of this architecture is the marginal zone (MZ), an area of the spleen that separates the reticuloendothelial red pulp of the spleen from the lymphoid white pulp compartment. There are two unique macrophage populations found in the MZ: MZ macrophages (MZM) found on the outer border of the MZ, and marginal metallophilic macrophages (MMM) found on the inner border, adjacent to the white pulp. We investigated the homeostasis of MMM and MZM following infection with Plasmodium chabaudi and demonstrated that a complete loss of both MMM and MZM occurred by the time of peak parasitemia, 8 days after infection. The loss was not induced by up-regulation of the inflammatory cytokines TNF or IFN-gamma. In contrast, following only CD8+ T cell depletion (not dendritic cell), MMM but not MZM were retained, implicating CD8+ T cells in the P. chabaudi-induced loss of MMM. Retention of MMM occurred in mice deficient in CD95, CD95-ligand, and perforin, indicating that these signals are involved in the death pathway of MMM. These data have significant implications for the understanding of the immune-mediated pathology of the spleen as a result of infection with Plasmodium.
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Affiliation(s)
- Lynette Beattie
- Molecular Immunology Laboratory, Queensland Institute of Medical Research, 300 Herston Road, P.O. Royal Brisbane Hospital, Brisbane 4029, Queensland, Australia
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Hernandez-Valladares M, Naessens J, Musoke AJ, Sekikawa K, Rihet P, Ole-Moiyoi OK, Busher P, Iraqi FA. Pathology of Tnf-deficient mice infected with Plasmodium chabaudi adami 408XZ. Exp Parasitol 2006; 114:271-8. [PMID: 16716303 DOI: 10.1016/j.exppara.2006.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2006] [Revised: 04/05/2006] [Accepted: 04/06/2006] [Indexed: 10/24/2022]
Abstract
Tumor necrosis factor alpha (Tnf) plays a pleiotropic role in murine malaria. Some investigations have correlated Tnf with hypothermia, hyperlactatemia, hypoglycemia, and a suppression of the erythropoietic response, although others have not. In this study, we have evaluated parasitemia, survival rate and several pathological features in C57BL/6JTnf(-/-) and C57BL/6JTnf(+/+) mice after infection with Plasmodium chabaudi adami 408XZ. Compared to the C57BL/6JTnf(+/+) mice, C57BL/6JTnf(-/-) mice showed increased parasitemia and decreased survival rate, whereas blood glucose, blood lactate and body weight were not significantly different. However, C57BL/6JTnf(-/-) mice suffered significantly more from severe anemia and hypothermia than C57BL/6JTnf(+/+) mice. These results suggest that Tnf is an important mediator of parasite control, but not of anemia development. We hypothesize that the high mortality observed in the Tnf knock-out mice is due to increased anemia and pathology as a direct result of increased levels of parasitemia.
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Affiliation(s)
- M Hernandez-Valladares
- International Livestock Research Institute (ILRI), Naivasha Road, P.O. Box 30709, 00100 Nairobi, Kenya.
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Abstract
Helminth infections, which are prevalent in areas where malaria is endemic, have been shown to modulate immune responses to unrelated pathogens and have been implicated in poor efficacy of malaria vaccines in humans. We established a murine coinfection model involving blood-stage Plasmodium chabaudi AS malaria and a gastrointestinal nematode, Heligmosomoides polygyrus, to investigate the impact of nematode infection on the protective efficacy of a malaria vaccine. C57BL/6 mice immunized with crude blood-stage P. chabaudi AS antigen in TiterMax adjuvant developed strong protection against malaria challenge. The same immunization protocol failed to induce strong protection in H. polygyrus-infected mice. Immunized nematode-infected mice produced significantly lower levels of malaria-specific antibody than nematode-free mice produced. In response to nematode and malarial antigens, spleen cells from immunized nematode-infected mice produced significantly lower levels of gamma interferon but more interleukin-4 (IL-4), IL-13, and IL-10 in vitro than spleen cells from immunized nematode-free mice produced. Furthermore, H. polygyrus infection also induced a strong transforming growth factor beta1 response in vivo and in vitro. Deworming treatment of H. polygyrus-infected mice before antimalarial immunization, but not deworming treatment after antimalarial immunization, restored the protective immunity to malaria challenge. These results demonstrate that concurrent nematode infection strongly modulates immune responses induced by an experimental malaria vaccine and consequently suppresses the protective efficacy of the vaccine against malaria challenge.
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Affiliation(s)
- Zhong Su
- Research Institute of McGill University Health Centre, Room L11-409, 1650 Cedar Avenue, Montreal, Quebec H3G 1A4, Canada.
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Maeno Y, Nakazawa S, Yamamoto N, Shinzato M, Nagashima S, Tanaka K, Sasaki J, Rittling SR, Denhardt DT, Uede T, Taniguchi K. Osteopontin participates in Th1-mediated host resistance against nonlethal malaria parasite Plasmodium chabaudi chabaudi infection in mice. Infect Immun 2006; 74:2423-7. [PMID: 16552072 PMCID: PMC1418913 DOI: 10.1128/iai.74.4.2423-2427.2006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Osteopontin (OPN) knockout mice (OPN-KO mice) died of Plasmodium chabaudi chabaudi infection, although wild-type (WT) mice had self-limiting infections. OPN was detected in the WT mice at 2 days postinfection. OPN-KO mice produced significantly smaller amounts of interleukin-12 and gamma interferon than WT mice produced. These results suggested that OPN is involved in Th1-mediated immunity against malaria infection.
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Affiliation(s)
- Yoshimasa Maeno
- Department of Virology and Parasitology, Fujita Health University School of Medicine, 1-98 Kutsukake, Toyoake, Aichi 470-1192, Japan.
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Cheesman S, Raza A, Carter R. Mixed Strain Infections and Strain-Specific Protective Immunity in the Rodent Malaria Parasite
Plasmodium chabaudi chabaudi
in Mice. Infect Immun 2006; 74:2996-3001. [PMID: 16622238 PMCID: PMC1459733 DOI: 10.1128/iai.74.5.2996-3001.2006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ABSTRACT
Important to malaria vaccine design is the phenomenon of “strain-specific” immunity. Using an accurate and sensitive assay of parasite genotype, real-time quantitative PCR, we have investigated protective immunity against mixed infections of genetically distinct cloned “strains” of the rodent malaria parasite
Plasmodium chabaudi chabaudi
in mice. Four strains of
P. c. chabaudi
, AS, AJ, AQ, and CB, were studied. One round of blood infection and drug cure with a single strain resulted in a partial reduction in parasitemia, compared with levels for naïve mice, in challenge infections with mixed inocula of the immunizing (homologous) strain and a heterologous strain. In all cases, the numbers of blood-stage parasites of each genotype were reduced to similar degrees. After a second, homologous round of infection and drug cure followed by challenge with homologous and heterologous strains, the parasitemias were reduced even further. In these circumstances, moreover, the homologous strain was reduced much faster than the heterologous strain in all of the combinations tested. That the immunity induced by a single infection did not show “strain specificity,” while the immunity following a second, homologous infection did, suggests that the “strain-specific” component of protective immunity in malaria may be dependent upon immune memory. The results show that strong, protective immunity induced by and effective against malaria parasites from a single parasite species has a significant “strain-specific” component and that this immunity operates differentially against genetically distinct parasites within the same infection.
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Affiliation(s)
- Sandra Cheesman
- School of Biological Sciences, Institute of Immunology and Infection Research, University of Edinburgh, The Kings Buildings, West Mains Road, Edinburgh EH9 3JT, United Kingdom.
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Abstract
The advent of new technologies and resources, including the complete sequence of mammalian genomes, has had a dramatic impact on the genetic analysis of susceptibility to infections in humans and in animal models of infection. Genes responsible for simple or complex control of susceptibility to infection with different pathogens have been recently identified and characterized, and are reviewed herein.
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Affiliation(s)
- Ashleigh Tuite
- Department of Biochemistry, McGill University, 3655 Promenade Sir William Osler, Room 907, Montreal, QC H3G 1Y6, Canada
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McDevitt MA, Xie J, Ganapathy-Kanniappan S, Shanmugasundaram G, Griffith J, Liu A, McDonald C, Thuma P, Gordeuk VR, Metz CN, Mitchell R, Keefer J, David J, Leng L, Bucala R. A critical role for the host mediator macrophage migration inhibitory factor in the pathogenesis of malarial anemia. ACTA ACUST UNITED AC 2006; 203:1185-96. [PMID: 16636133 PMCID: PMC2121202 DOI: 10.1084/jem.20052398] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The pathogenesis of malarial anemia is multifactorial, and the mechanisms responsible for its high mortality are poorly understood. Studies indicate that host mediators produced during malaria infection may suppress erythroid progenitor development (Miller, K.L., J.C. Schooley, K.L. Smith, B. Kullgren, L.J. Mahlmann, and P.H. Silverman. 1989. Exp. Hematol. 17:379–385; Yap, G.S., and M.M. Stevenson. 1991. Ann. NY Acad. Sci. 628:279–281). We describe an intrinsic role for macrophage migration inhibitory factor (MIF) in the development of the anemic complications and bone marrow suppression that are associated with malaria infection. At concentrations found in the circulation of malaria-infected patients, MIF suppressed erythropoietin-dependent erythroid colony formation. MIF synergized with tumor necrosis factor and γ interferon, which are known antagonists of hematopoiesis, even when these cytokines were present in subinhibitory concentrations. MIF inhibited erythroid differentiation and hemoglobin production, and it antagonized the pattern of mitogen-activated protein kinase phosphorylation that normally occurs during erythroid progenitor differentiation. Infection of MIF knockout mice with Plasmodium chabaudi resulted in less severe anemia, improved erythroid progenitor development, and increased survival compared with wild-type controls. We also found that human mononuclear cells carrying highly expressed MIF alleles produced more MIF when stimulated with the malarial product hemozoin compared with cells carrying low expression MIF alleles. These data suggest that polymorphisms at the MIF locus may influence the levels of MIF produced in the innate response to malaria infection and the likelihood of anemic complications.
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Affiliation(s)
- Michael A McDevitt
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Marques CS, Rolão N, Centeno-Lima S, Lousada H, Maia C, Campino L, do Rosário VE, Silveira H. Studies in a co-infection murine model of Plasmodium chabaudi chabaudi and Leishmania infantum: interferon-gamma and interleukin-4 mRNA expression. Mem Inst Oswaldo Cruz 2006; 100:889-92. [PMID: 16444421 DOI: 10.1590/s0074-02762005000800011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This work aimed to study the T helper type 1/2 (Th1/Th2) cytokine profile in a co-infection murine model of Plasmodium chabaudi chabaudi and Leishmania infantum. Expression of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) was analyzed, in spleen and liver of C57BL/6 mice, by reverse transcriptase-polymerase chain reaction. High levels of IFN-gamma expression did not prevent the progression of Leishmania in co-infected mice and Leishmania infection did not interfere with the Th1/Th2 switch necessary for Plasmodium control. The presence of IL-4 at day 28 in co-infected mice, essential for Plasmodium elimination, was probably a key factor on the exacerbation of the Leishmania infection.
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Affiliation(s)
- Cláudia S Marques
- Unidade de Leishmanioses, Centro de Malária e Doenças Tropicais, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa
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