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Pollenus E, Prenen F, Possemiers H, Knoops S, Mitera T, Lamote J, De Visscher A, Vandermosten L, Pham TT, Matthys P, Van den Steen PE. Aspecific binding of anti-NK1.1 antibodies on myeloid cells in an experimental model for malaria-associated acute respiratory distress syndrome. Malar J 2024; 23:110. [PMID: 38637828 PMCID: PMC11025177 DOI: 10.1186/s12936-024-04944-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/12/2024] [Indexed: 04/20/2024] Open
Abstract
BACKGROUND Conventional natural killer (cNK) cells play an important role in the innate immune response by directly killing infected and malignant cells and by producing pro- and anti-inflammatory cytokines. Studies on their role in malaria and its complications have resulted in conflicting results. METHODS Using the commonly used anti-NK1.1 depletion antibodies (PK136) in an in-house optimized experimental model for malaria-associated acute respiratory distress syndrome (MA-ARDS), the role of cNK cells was investigated. Moreover, flow cytometry was performed to characterize different NK cell populations. RESULTS While cNK cells were found to be dispensable in the development of MA-ARDS, the appearance of a NK1.1+ cell population was observed in the lungs upon infection despite depletion with anti-NK1.1. Detailed characterization of the unknown population revealed that this population consisted of a mixture of monocytes and macrophages that bind the anti-NK1.1 antibody in an aspecific way. This aspecific binding may occur via Fcγ receptors, such as FcγR4. In contrast, in vivo depletion using anti-NK1.1 antibodies was proved to be specific for cNK cells. CONCLUSION cNK cells are dispensable in the development of experimental MA-ARDS. Moreover, careful flow cytometric analysis, with a critical mindset in relation to potential aspecific binding despite the use of commercially available Fc blocking reagents, is critical to avoid misinterpretation of the results.
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Affiliation(s)
- Emilie Pollenus
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Fran Prenen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Tania Mitera
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Jochen Lamote
- Laboratory for Molecular Cancer Biology, Department of Oncology, VIB, KU Leuven, Leuven, Belgium
| | - Amber De Visscher
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
- Currently at Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Patrick Matthys
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium.
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2
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Chauhan R, Tiwari M, Chaudhary A, Sharan Thakur R, Pande V, Das J. Chemokines: A key driver for inflammation in protozoan infection. Int Rev Immunol 2023; 43:211-228. [PMID: 37980574 DOI: 10.1080/08830185.2023.2281566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 10/16/2023] [Indexed: 11/21/2023]
Abstract
Chemokines belong to the group of small proteins within the cytokine family having strong chemo-attractant properties. In most cases, the strong immuno-modulatory role of chemokines is crucial for generating the immune response against pathogens in various protozoan diseases. In this review, we have given a brief update on the classification, characterization, homeostasis, transcellular migration, and immuno-modulatory role of chemokines. Here we will evaluate the potential role of chemokines and their regulation in various protozoan diseases. There is a significant direct relationship between parasitic infection and the recruitment of effector cells of the immune response. Chemokines play an indispensable role in mediating several defense mechanisms against infection, such as leukocyte recruitment and the generation of innate and cell-mediated immunity that aids in controlling/eliminating the pathogen. This process is controlled by the chemotactic movement of chemokines induced as a primary host immune response. We have also addressed that chemokine expressions during infection are time-dependent and orchestrated in a systematic pattern that ultimately assists in generating a protective immune response. Taken together, this review provides a systematic understanding of the complexity of chemokines profiles during protozoan disease conditions and the rationale of targeting chemokines for the development of therapeutic strategies.
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Affiliation(s)
- Rubika Chauhan
- Parasite-Host Biology, National Institute of Malaria Research, Dwarka, New Delhi, India
| | - Mrinalini Tiwari
- Parasite-Host Biology, National Institute of Malaria Research, Dwarka, New Delhi, India
| | - Amrendra Chaudhary
- Parasite-Host Biology, National Institute of Malaria Research, Dwarka, New Delhi, India
| | - Reva Sharan Thakur
- Parasite-Host Biology, National Institute of Malaria Research, Dwarka, New Delhi, India
| | - Veena Pande
- Biotechnology Department, Kumaun University, Nainital, India
| | - Jyoti Das
- Parasite-Host Biology, National Institute of Malaria Research, Dwarka, New Delhi, India
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3
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Olatunde AC, Cornwall DH, Roedel M, Lamb TJ. Mouse Models for Unravelling Immunology of Blood Stage Malaria. Vaccines (Basel) 2022; 10:1525. [PMID: 36146602 PMCID: PMC9501382 DOI: 10.3390/vaccines10091525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 11/16/2022] Open
Abstract
Malaria comprises a spectrum of disease syndromes and the immune system is a major participant in malarial disease. This is particularly true in relation to the immune responses elicited against blood stages of Plasmodium-parasites that are responsible for the pathogenesis of infection. Mouse models of malaria are commonly used to dissect the immune mechanisms underlying disease. While no single mouse model of Plasmodium infection completely recapitulates all the features of malaria in humans, collectively the existing models are invaluable for defining the events that lead to the immunopathogenesis of malaria. Here we review the different mouse models of Plasmodium infection that are available, and highlight some of the main contributions these models have made with regards to identifying immune mechanisms of parasite control and the immunopathogenesis of malaria.
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Affiliation(s)
| | | | | | - Tracey J. Lamb
- Department of Pathology, University of Utah, Emma Eccles Jones Medical Research Building, 15 N Medical Drive E, Room 1420A, Salt Lake City, UT 84112, USA
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4
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Kumarasingha R, Ioannidis LJ, Abeysekera W, Studniberg S, Wijesurendra D, Mazhari R, Poole DP, Mueller I, Schofield L, Hansen DS, Eriksson EM. Transcriptional Memory-Like Imprints and Enhanced Functional Activity in γδ T Cells Following Resolution of Malaria Infection. Front Immunol 2020; 11:582358. [PMID: 33154754 PMCID: PMC7591758 DOI: 10.3389/fimmu.2020.582358] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 09/21/2020] [Indexed: 11/18/2022] Open
Abstract
γδ T cells play an essential role in the immune response to many pathogens, including Plasmodium. However, long-lasting effects of infection on the γδ T cell population still remain inadequately understood. This study focused on assessing molecular and functional changes that persist in the γδ T cell population following resolution of malaria infection. We investigated transcriptional changes and memory-like functional capacity of malaria pre-exposed γδ T cells using a Plasmodiumchabaudi infection model. We show that multiple genes associated with effector function (chemokines, cytokines and cytotoxicity) and antigen-presentation were upregulated in P. chabaudi-exposed γδ T cells compared to γδ T cells from naïve mice. This transcriptional profile was positively correlated with profiles observed in conventional memory CD8+ T cells and was accompanied by enhanced reactivation upon secondary encounter with Plasmodium-infected red blood cells in vitro. Collectively our data demonstrate that Plasmodium exposure result in "memory-like imprints" in the γδ T cell population and also promotes γδ T cells that can support antigen-presentation during subsequent infections.
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Affiliation(s)
- Rasika Kumarasingha
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Lisa J. Ioannidis
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Waruni Abeysekera
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Stephanie Studniberg
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Dinidu Wijesurendra
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Ramin Mazhari
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Daniel P. Poole
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Louis Schofield
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- School of Veterinary and Biomedical Sciences, James Cook University, Townsville, QLD, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, QLD, Australia
| | - Diana S. Hansen
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Emily M. Eriksson
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
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5
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Antonelli LR, Junqueira C, Vinetz JM, Golenbock DT, Ferreira MU, Gazzinelli RT. The immunology of Plasmodium vivax malaria. Immunol Rev 2019; 293:163-189. [PMID: 31642531 DOI: 10.1111/imr.12816] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 09/10/2019] [Indexed: 12/13/2022]
Abstract
Plasmodium vivax infection, the predominant cause of malaria in Asia and Latin America, affects ~14 million individuals annually, with considerable adverse effects on wellbeing and socioeconomic development. A clinical hallmark of Plasmodium infection, the paroxysm, is driven by pyrogenic cytokines produced during the immune response. Here, we review studies on the role of specific immune cell types, cognate innate immune receptors, and inflammatory cytokines on parasite control and disease symptoms. This review also summarizes studies on recurrent infections in individuals living in endemic regions as well as asymptomatic infections, a serious barrier to eliminating this disease. We propose potential mechanisms behind these repeated and subclinical infections, such as poor induction of immunological memory cells and inefficient T effector cells. We address the role of antibody-mediated resistance to P. vivax infection and discuss current progress in vaccine development. Finally, we review immunoregulatory mechanisms, such as inhibitory receptors, T regulatory cells, and the anti-inflammatory cytokine, IL-10, that antagonizes both innate and acquired immune responses, interfering with the development of protective immunity and parasite clearance. These studies provide new insights for the clinical management of symptomatic as well as asymptomatic individuals and the development of an efficacious vaccine for vivax malaria.
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Affiliation(s)
- Lis R Antonelli
- Instituto de Pesquisas Rene Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil
| | - Caroline Junqueira
- Instituto de Pesquisas Rene Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil
| | - Joseph M Vinetz
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Douglas T Golenbock
- Division of Infectious Disease and immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Marcelo U Ferreira
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Ricardo T Gazzinelli
- Instituto de Pesquisas Rene Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil.,Division of Infectious Disease and immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA.,Plataforma de Medicina Translacional, Fundação Oswaldo Cruz, Ribeirão Preto, Brazil
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6
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Burrack KS, Hart GT, Hamilton SE. Contributions of natural killer cells to the immune response against Plasmodium. Malar J 2019; 18:321. [PMID: 31533835 PMCID: PMC6751859 DOI: 10.1186/s12936-019-2953-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/07/2019] [Indexed: 01/08/2023] Open
Abstract
Natural killer (NK) cells are important innate effector cells that are well described in their ability to kill virally-infected cells and tumors. However, there is increasing appreciation for the role of NK cells in the control of other pathogens, including intracellular parasites such as Plasmodium, the cause of malaria. NK cells may be beneficial during the early phase of Plasmodium infection—prior to the activation and expansion of antigen-specific T cells—through cooperation with myeloid cells to produce inflammatory cytokines like IFNγ. Recent work has defined how Plasmodium can activate NK cells to respond with natural cytotoxicity, and inhibit the growth of parasites via antibody-dependent cellular cytotoxicity mechanisms (ADCC). A specialized subset of adaptive NK cells that are negative for the Fc receptor γ chain have enhanced ADCC function and correlate with protection from malaria. Additionally, production of the regulatory cytokine IL-10 by NK cells prevents overt pathology and death during experimental cerebral malaria. Now that conditional NK cell mouse models have been developed, previous studies need to be reevaluated in the context of what is now known about other immune populations with similarity to NK cells (i.e., NKT cells and type I innate lymphoid cells). This brief review summarizes recent findings which support the potentially beneficial roles of NK cells during Plasmodium infection in mice and humans. Also highlighted are how the actions of NK cells can be explored using new experimental strategies, and the potential to harness NK cell function in vaccination regimens.
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Affiliation(s)
- Kristina S Burrack
- Department of Medicine, Hennepin Healthcare Research Institute, Minneapolis, MN, 55415, USA
| | - Geoffrey T Hart
- Center for Immunology, Department of Medicine, Division of Infectious Disease and International Medicine, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Sara E Hamilton
- Center for Immunology, Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, 55414, USA.
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7
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Ng SS, Engwerda CR. Innate Lymphocytes and Malaria - Players or Spectators? Trends Parasitol 2018; 35:154-162. [PMID: 30579700 DOI: 10.1016/j.pt.2018.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/29/2018] [Accepted: 11/29/2018] [Indexed: 12/19/2022]
Abstract
Malaria remains an important global disease. Despite significant advances over the past decade in reducing disease morbidity and mortality, new measures are needed if malaria is to be eliminated. Significant advances in our understanding about host immune responses during malaria have been made, opening up opportunities to generate long-lasting antiparasitic immunity through vaccination or immune therapy. However, there is still much debate over which immune cell populations contribute to immunity to malaria, including innate lymphocytes that comprise recently identified innate lymphoid cells (ILCs) and better known innate-like T cell subsets. Here, we review research on these immune cell subsets and discuss whether they have any important roles in immunity to malaria or if they are redundant.
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Affiliation(s)
- Susanna S Ng
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, QLD, Australia; School of Environment and Science, Griffith University, QLD, Australia
| | - Christian R Engwerda
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, QLD, Australia.
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8
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Controlled Infection Immunization Using Delayed Death Drug Treatment Elicits Protective Immune Responses to Blood-Stage Malaria Parasites. Infect Immun 2018; 87:IAI.00587-18. [PMID: 30323025 PMCID: PMC6300636 DOI: 10.1128/iai.00587-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 09/23/2018] [Indexed: 01/27/2023] Open
Abstract
Naturally acquired immunity to malaria is robust and protective against all strains of the same species of Plasmodium. This develops as a result of repeated natural infection, taking several years to develop. Naturally acquired immunity to malaria is robust and protective against all strains of the same species of Plasmodium. This develops as a result of repeated natural infection, taking several years to develop. Evidence suggests that apoptosis of immune lymphocytes due to uncontrolled parasite growth contributes to the slow acquisition of immunity. To hasten and augment the development of natural immunity, we studied controlled infection immunization (CII) using low-dose exposure to different parasite species (Plasmodium chabaudi, P. yoelii, or P. falciparum) in two rodent systems (BALB/c and C57BL/6 mice) and in human volunteers, with drug therapy commencing at the time of initiation of infection. CIIs with infected erythrocytes and in conjunction with doxycycline or azithromycin, which are delayed death drugs targeting the parasite’s apicoplast, allowed extended exposure to parasites at low levels. In turn, this induced strong protection against homologous challenge in all immunized mice. We show that P. chabaudi/P. yoelii infection initiated at the commencement of doxycycline therapy leads to cellular or antibody-mediated protective immune responses in mice, with a broad Th1 cytokine response providing the best correlate of protection against homologous and heterologous species of Plasmodium. P. falciparum CII with doxycycline was additionally tested in a pilot clinical study (n = 4) and was found to be well tolerated and immunogenic, with immunological studies primarily detecting increased cell-associated immune responses. Furthermore, we report that a single dose of the longer-acting drug, azithromycin, given to mice (n = 5) as a single subcutaneous treatment at the initiation of infection controlled P. yoelii infection and protected all mice against subsequent challenge.
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9
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Dantzler KW, Jagannathan P. γδ T Cells in Antimalarial Immunity: New Insights Into Their Diverse Functions in Protection and Tolerance. Front Immunol 2018; 9:2445. [PMID: 30405634 PMCID: PMC6206268 DOI: 10.3389/fimmu.2018.02445] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 10/03/2018] [Indexed: 12/19/2022] Open
Abstract
Uniquely expressing diverse innate-like and adaptive-like functions, γδ T cells exist as specialized subsets, but are also able to adapt in response to environmental cues. These cells have long been known to rapidly proliferate following primary malaria infection in humans and mice, but exciting new work is shedding light into their diverse functions in protection and following repeated malaria infection. In this review, we examine the current knowledge of functional specialization of γδ T cells in malaria, and the mechanisms dictating recognition of malaria parasites and resulting proliferation. We discuss γδ T cell plasticity, including changing interactions with other immune cells during recurrent infection and potential for immunological memory in response to repeated stimulation. Building on recent insights from human and murine experimental studies and vaccine trials, we propose areas for future research, as well as applications for therapeutic development.
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10
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Wikenheiser DJ, Brown SL, Lee J, Stumhofer JS. NK1.1 Expression Defines a Population of CD4 + Effector T Cells Displaying Th1 and Tfh Cell Properties That Support Early Antibody Production During Plasmodium yoelii Infection. Front Immunol 2018; 9:2277. [PMID: 30374346 PMCID: PMC6196288 DOI: 10.3389/fimmu.2018.02277] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 09/13/2018] [Indexed: 11/23/2022] Open
Abstract
Early plasmablast induction is a hallmark of Plasmodium infection and is thought to contribute to the control of acute parasite burden. Although long understood to be a T-cell dependent phenomenon, regulation of early plasmablast differentiation, however, is poorly understood. Here, we identify a population of CD4+ T cells that express the innate NK cell marker NK1.1 as an important source of T cell help for early plasmablast and parasite-specific Ab production. Interestingly, NK1.1+ CD4+ T cells arise from conventional, naive NK1.1− CD4+ T cells, and their generation is independent of CD1d but critically reliant on MHC-II. CD4+ T cells that express NK1.1 early after activation produce IFN-γ and IL-21, and express the follicular helper T (Tfh) cell markers ICOS, PD-1 and CXCR5 more frequently than NK1.1− CD4+ T cells. Further analysis of this population revealed that NK1.1+ Tfh-like cells were more regularly complexed with plasmablasts than NK1.1− Tfh-like cells. Ultimately, depletion of NK1.1+ cells impaired class-switched parasite-specific antibody production during early Plasmodium yoelii infection. Together, these data suggest that expression of NK1.1 defines a population of rapidly expanding effector CD4+ T cells that specifically promote plasmablast induction during Plasmodium infection and represent a subset of T cells whose modulation could promote effective vaccine design.
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Affiliation(s)
- Daniel J Wikenheiser
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Susie L Brown
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Juhyung Lee
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Jason S Stumhofer
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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11
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Inoue SI, Niikura M, Asahi H, Kawakami Y, Kobayashi F. γδ T cells modulate humoral immunity against Plasmodium berghei infection. Immunology 2018; 155:519-532. [PMID: 30144035 DOI: 10.1111/imm.12997] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/07/2018] [Accepted: 08/12/2018] [Indexed: 01/22/2023] Open
Abstract
It is unclear whether γδ T cells are involved in humoral immunity against Plasmodium infection. Here, we show that B-cell-immunodeficient mice and γδ T-cell-deficient mice were incapable of protecting against Plasmodium berghei XAT parasites. γδ T-cell-deficient mice developed reduced levels of antigen-specific antibodies during the late phase of infection. The numbers of follicular helper T cells and germinal centre B cells in γδ T-cell-deficient mice were lower than in wild-type mice during the late phase of infection. Expression profiling of humoral immunity-related cytokines in γδ T cells showed that interleukin-21 (IL-21) and interferon-γ (IFN-γ) are increased during the early stage of infection. Furthermore, blockade of IL-21 and IFN-γ signalling during the early stage of infection led to reduction in follicular helper T cells and germinal centre B cells. γδ T-cell production of IL-21 and IFN-γ is crucial for the development and maintenance of follicular helper T cells and germinal centre B cells during the late phase of infection. Our data suggest that γδ T cells modulate humoral immunity against Plasmodium infection.
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Affiliation(s)
- Shin-Ichi Inoue
- Division of Immunology, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
| | - Mamoru Niikura
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
| | - Hiroko Asahi
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
| | - Yasushi Kawakami
- Laboratory of Parasitology, School of Life and Environmental Science, Azabu University, Kanagawa, Japan
| | - Fumie Kobayashi
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan.,Laboratory of Parasitology, School of Life and Environmental Science, Azabu University, Kanagawa, Japan
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12
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Ng SS, Souza-Fonseca-Guimaraes F, Rivera FDL, Amante FH, Kumar R, Gao Y, Sheel M, Beattie L, Montes de Oca M, Guillerey C, Edwards CL, Faleiro RJ, Frame T, Bunn PT, Vivier E, Godfrey DI, Pellicci DG, Lopez JA, Andrews KT, Huntington ND, Smyth MJ, McCarthy J, Engwerda CR. Rapid loss of group 1 innate lymphoid cells during blood stage Plasmodium infection. Clin Transl Immunology 2018; 7:e1003. [PMID: 29484181 PMCID: PMC5822408 DOI: 10.1002/cti2.1003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/09/2017] [Accepted: 12/05/2017] [Indexed: 12/20/2022] Open
Abstract
Objectives Innate lymphoid cells (ILCs) share many characteristics with CD4+ T cells, and group 1 ILCs share a requirement for T‐bet and the ability to produce IFNγ with T helper 1 (Th1) cells. Given this similarity, and the importance of Th1 cells for protection against intracellular protozoan parasites, we aimed to characterise the role of group 1 ILCs during Plasmodium infection. Methods We quantified group 1 ILCs in peripheral blood collected from subjects infected with with Plasmodium falciparum 3D7 as part of a controlled human malaria infection study, and in the liver and spleens of PcAS‐infected mice. We used genetically‐modified mouse models, as well as cell‐depletion methods in mice to characterise the role of group 1 ILCs during PcAS infection. Results In a controlled human malaria infection study, we found that the frequencies of circulating ILC1s and NK cells decreased as infection progressed but recovered after volunteers were treated with antiparasitic drug. A similar observation was made for liver and splenic ILC1s in P. chabaudi chabaudi AS (PcAS)‐infected mice. The decrease in mouse liver ILC1 frequencies was associated with increased apoptosis. We also identified a population of cells within the liver and spleen that expressed both ILC1 and NK cell markers, indicative of plasticity between these two cell lineages. Studies using genetic and cell‐depletion approaches indicated that group 1 ILCs have a limited role in antiparasitic immunity during PcAS infection in mice. Discussion Our results are consistent with a previous study indicating a limited role for natural killer (NK) cells during Plasmodium chabaudi infection in mice. Additionally, a recent study reported the redundancy of ILCs in humans with competent B and T cells. Nonetheless, our results do not rule out a role for group 1 ILCs in human malaria in endemic settings given that blood stage infection was initiated intravenously in our experimental models, and thus bypassed the liver stage of infection, which may influence the immune response during the blood stage. Conclusion Our results show that ILC1s are lost early during mouse and human malaria, and this observation may help to explain the limited role for these cells in controlling blood stage infection.
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Affiliation(s)
- Susanna S Ng
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia.,School of Natural Sciences Griffith University Nathan QLD Australia
| | - Fernando Souza-Fonseca-Guimaraes
- Faculty of Medicine, Dentistry and Health Sciences University of Melbourne Melbourne VIC Australia.,Molecular Immunology Division The Walter and Eliza Hall Institute of Medical Research Parkville VIC Australia
| | | | - Fiona H Amante
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Rajiv Kumar
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia.,Department of Biochemistry Banaras Hindu University Varanasi India
| | - Yulong Gao
- Immunology in Cancer and Infection QIMR Berghofer Medical Research Institute Herston QLD Australia.,School of Medicine University of Queensland Herston QLD Australia
| | - Meru Sheel
- National Centre for Immunisation Research and Surveillance Westmead NSW Australia
| | - Lynette Beattie
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Marcela Montes de Oca
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Camille Guillerey
- Immunology in Cancer and Infection QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Chelsea L Edwards
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia.,School of Medicine University of Queensland Herston QLD Australia
| | - Rebecca J Faleiro
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Teija Frame
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Patrick T Bunn
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Eric Vivier
- Aix Marseille Université, CNRS, INSERM, CIML Marseille France.,Service d'Immunologie APHM, Hôpital de la Conception Marseille France
| | - Dale I Godfrey
- Department of Microbiology and Immunology Peter Doherty Institute for Infection and Immunity University of Melbourne Melbourne VIC Australia.,Australian Research Council Centre of Excellence for Advanced Molecular Imaging University of Melbourne Melbourne VIC Australia
| | - Daniel G Pellicci
- Department of Microbiology and Immunology Peter Doherty Institute for Infection and Immunity University of Melbourne Melbourne VIC Australia.,Australian Research Council Centre of Excellence for Advanced Molecular Imaging University of Melbourne Melbourne VIC Australia
| | | | | | - Nicholas D Huntington
- Molecular Immunology Division The Walter and Eliza Hall Institute of Medical Research Parkville VIC Australia.,Department of Medical Biology The University of Melbourne Melbourne VIC Australia
| | - Mark J Smyth
- Immunology in Cancer and Infection QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - James McCarthy
- Clinical Tropical Medicine QIMR Berghofer Medical Research Institute Herston QLD Australia
| | - Christian R Engwerda
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Herston QLD Australia
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13
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Ueffing K, Abberger H, Westendorf AM, Matuschewski K, Buer J, Hansen W. Conventional CD11c high Dendritic Cells Are Important for T Cell Priming during the Initial Phase of Plasmodium yoelii Infection, but Are Dispensable at Later Time Points. Front Immunol 2017; 8:1333. [PMID: 29085373 PMCID: PMC5650681 DOI: 10.3389/fimmu.2017.01333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/02/2017] [Indexed: 12/20/2022] Open
Abstract
Dendritic cells (DCs) are highly specialized antigen-presenting cells that orchestrate adaptive immune responses to pathogens. During malaria infection pro- and anti-inflammatory T cell responses have to be tightly balanced to ensure parasite clearance without induction of severe immune pathologies. However, the precise role of CD11chigh DCs in this process is still discussed controversially. Here, we demonstrate that long-term depletion of conventional CD11chigh DCs in Plasmodium yoelii (P. yoelii)-infected diphtheria toxin (DT)-treated RosaiDTR/CD11c-cre mice interferes with the activation of CD8+ and CD4+ T cells as well as CD4+Foxp3+ regulatory T cells at early time points during infection. Moreover, systemic levels of the pro-inflammatory cytokines IFN-γ and TNF-α were decreased in P. yoelii-infected mice deficient for CD11chigh DCs compared to infected RosaiDTR controls. To further elucidate the importance of CD11chigh DCs during the later phase of infection, we treated RosaiDTR/CD11c-cre and control mice with DT only from day 4 of P. yoelii infection onward. Strikingly, this approach had no impact on the activation and IFN-γ production of CD4+ and CD8+ effector T cells. These results indicate that CD11chigh DCs play a crucial role in eliciting effector T cell responses during the initial phase, but are dispensable during ongoing infection with P. yoelii.
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Affiliation(s)
- Kristina Ueffing
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Hanna Abberger
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Astrid M Westendorf
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Kai Matuschewski
- Molecular Parasitology, Institute of Biology, Humboldt University of Berlin, Berlin, Germany
| | - Jan Buer
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Wiebke Hansen
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
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14
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Neutrophils Are Central to Antibody-Mediated Protection against Genital Chlamydia. Infect Immun 2017; 85:IAI.00409-17. [PMID: 28739831 PMCID: PMC5607418 DOI: 10.1128/iai.00409-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 07/18/2017] [Indexed: 12/17/2022] Open
Abstract
Determining the effector populations involved in humoral protection against genital chlamydia infection is crucial to development of an effective chlamydial vaccine. Antibody has been implicated in protection studies in multiple animal models, and we previously showed that the passive transfer of immune serum alone does not confer immunity in the mouse. Using the Chlamydia muridarum model of genital infection, we demonstrate a protective role for both Chlamydia-specific immunoglobulin G (IgG) and polymorphonuclear neutrophils and show the importance of an antibody/effector cell interaction in mediating humoral immunity. While neutrophils were found to contribute significantly to antibody-mediated protection in vivo, natural killer (NK) cells were dispensable for protective immunity. Furthermore, gamma interferon (IFN-γ)-stimulated primary peritoneal neutrophils (PPNs) killed chlamydiae in vitro in an antibody-dependent manner. The results from this study support the view that an IFN-γ-activated effector cell population cooperates with antibody to protect against genital chlamydia and establish neutrophils as a key effector cell in this response.
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15
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Barber BE, Grigg MJ, William T, Piera KA, Boyle MJ, Yeo TW, Anstey NM. Effects of Aging on Parasite Biomass, Inflammation, Endothelial Activation, Microvascular Dysfunction and Disease Severity in Plasmodium knowlesi and Plasmodium falciparum Malaria. J Infect Dis 2017; 215:1908-1917. [PMID: 28863470 DOI: 10.1093/infdis/jix193] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/15/2017] [Indexed: 02/06/2023] Open
Abstract
Background In populations pauci-immune to malaria, risk of severe malaria increases with age. This is particularly apparent in Plasmodium knowlesi malaria. However, pathophysiological mechanisms underlying knowlesi malaria, and of the age-related increase in risk of severe malaria in general, are poorly understood. Methods In Malaysian patients aged ≥12 years with severe (n = 47) and nonsevere (n = 99) knowlesi malaria, severe (n = 21) and nonsevere (n = 109) falciparum malaria, and healthy controls (n = 50), we measured parasite biomass, systemic inflammation (interleukin 6 [IL-6]), endothelial activation (angiopoietin-2), and microvascular function, and evaluated the effects of age. Results Plasmodium knowlesi parasitemia correlated with age (Spearman's correlation coefficient [rs] = 0.36; P < .0001). In knowlesi malaria, IL-6, angiopoietin-2, and microvascular dysfunction were increased in severe compared to nonsevere disease, and all correlated with age, independent of parasitemia. In falciparum malaria, angiopoietin-2 increased with age, independent of parasite biomass (histidine-rich protein 2 [HRP2]). Independent risk factors for severe malaria included parasitemia and angiopoietin-2 in knowlesi malaria, and HRP2, angiopoietin-2, and microvascular dysfunction in falciparum malaria. Conclusions Parasite biomass, endothelial activation, and microvascular dysfunction are associated with severe disease in knowlesi malaria and likely contribute to pathogenesis. The association of each of these processes with aging may account for the greater severity of malaria observed in older adults in low-endemic regions.
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Affiliation(s)
- Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital
| | - Timothy William
- Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital.,Jesselton Medical Centre, Kota Kinabalu, Sabah, Malaysia
| | - Kim A Piera
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia
| | - Michelle J Boyle
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Centre for Biomedical Research, Burnet Institute, Melbourne, Victoria, Australia
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital.,Lee Kong Chian School of Medicine, Nanyang Technological University.,Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital
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16
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Schofield L, Ioannidis LJ, Karl S, Robinson LJ, Tan QY, Poole DP, Betuela I, Hill DL, Siba PM, Hansen DS, Mueller I, Eriksson EM. Synergistic effect of IL-12 and IL-18 induces TIM3 regulation of γδ T cell function and decreases the risk of clinical malaria in children living in Papua New Guinea. BMC Med 2017; 15:114. [PMID: 28615061 PMCID: PMC5471992 DOI: 10.1186/s12916-017-0883-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Accepted: 05/22/2017] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND γδ T cells are important for both protective immunity and immunopathogenesis during malaria infection. However, the immunological processes determining beneficial or detrimental effects on disease outcome remain elusive. The aim of this study was to examine expression and regulatory effect of the inhibitory receptor T-cell immunoglobulin domain and mucin domain 3 (TIM3) on γδ T cells. While TIM3 expression and function on conventional αβ T cells have been clearly defined, the equivalent characterization on γδ T cells and associations with disease outcomes is limited. This study investigated the functional capacity of TIM3+ γδ T cells and the underlying mechanisms contributing to TIM3 upregulation and established an association with malaria disease outcomes. METHODS We analyzed TIM3 expression on γδ T cells in 132 children aged 5-10 years living in malaria endemic areas of Papua New Guinea. TIM3 upregulation and effector functions of TIM3+ γδ T cells were assessed following in vitro stimulation with parasite-infected erythrocytes, phosphoantigen and/or cytokines. Associations between the proportion of TIM3-expressing cells and the molecular force of infection were tested using negative binomial regression and in a Cox proportional hazards model for time to first clinical episode. Multivariable analyses to determine the association of TIM3 and IL-18 levels were conducted using general linear models. Malaria infection mouse models were utilized to experimentally investigate the relationship between repeated exposure and TIM3 upregulation. RESULTS This study demonstrates that even in the absence of an active malaria infection, children of malaria endemic areas have an atypical population of TIM3-expressing γδ T cells (mean frequency TIM3+ of total γδ T cells 15.2% ± 12). Crucial factors required for γδ T cell TIM3 upregulation include IL-12/IL-18, and plasma IL-18 was associated with TIM3 expression (P = 0.002). Additionally, we show a relationship between TIM3 expression and infection with distinct parasite clones during repeated exposure. TIM3+ γδ T cells were functionally impaired and were associated with asymptomatic malaria infection (hazard ratio 0.54, P = 0.032). CONCLUSIONS Collectively our data demonstrate a novel role for IL-12/IL-18 in shaping the innate immune response and provide fundamental insight into aspects of γδ T cell immunoregulation. Furthermore, we show that TIM3 represents an important γδ T cell regulatory component involved in minimizing malaria symptoms.
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Affiliation(s)
- Louis Schofield
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, QLD, 4811, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Lisa J Ioannidis
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Stephan Karl
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Leanne J Robinson
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia.,Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea.,Burnet Institute, Melbourne, VIC, 3004, Australia
| | - Qiao Y Tan
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Daniel P Poole
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, 3052, Australia.,Department of Anatomy and Neuroscience, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Inoni Betuela
- Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea
| | - Danika L Hill
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea.,School of Veterinary and Biomedical Sciences, James Cook University, Townsville, QLD, 4811, Australia
| | - Diana S Hansen
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Emily M Eriksson
- Walter and Eliza Hall Institute of Medical Research, Division of Population Health and Immunity, Melbourne, VIC, 3052, Australia. .,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3052, Australia. .,The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC, 3052, Australia.
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17
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Wolf AS, Sherratt S, Riley EM. NK Cells: Uncertain Allies against Malaria. Front Immunol 2017; 8:212. [PMID: 28337195 PMCID: PMC5343013 DOI: 10.3389/fimmu.2017.00212] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 02/15/2017] [Indexed: 12/24/2022] Open
Abstract
Until recently, studies of natural killer (NK) cells in infection have focused almost entirely on their role in viral infections. However, there is an increasing awareness of the potential for NK cells to contribute to the control of a wider range of pathogens, including intracellular parasites such as Plasmodium spp. Given the high prevalence of parasitic diseases in the developing world and the devastating effects these pathogens have on large numbers of vulnerable people, investigating interactions between NK cells and parasitized host cells presents the opportunity to reveal novel immunological mechanisms with the potential to aid efforts to eradicate these diseases. The capacity of NK cells to produce inflammatory cytokines early after malaria infection, as well as a possible role in direct cytotoxic killing of malaria-infected cells, suggests a beneficial impact of NK cells in this disease. However, NK cells may also contribute to overproduction of pro-inflammatory cytokines and the consequent immunopathology. As comparatively little is known about the role of NK cells later in the course of infection, and growing evidence suggests that heterogeneity in NK cell responses to malaria may be influenced by KIR/HLA interactions, a better understanding of the mechanisms by which NK cells might directly interact with parasitized cells may reveal a new role for these cells in the course of malaria infection.
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Affiliation(s)
- Asia-Sophia Wolf
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine , London , UK
| | - Samuel Sherratt
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine , London , UK
| | - Eleanor M Riley
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine , London , UK
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18
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Abstract
SUMMARYProtists are a diverse collection of eukaryotic organisms that account for a significant global infection burden. Often, the immune responses mounted against these parasites cause excessive inflammation and therefore pathology in the host. Elucidating the mechanisms of both protective and harmful immune responses is complex, and often relies of the use of animal models. In any immune response, leucocyte trafficking to the site of infection, or inflammation, is paramount, and this involves the production of chemokines, small chemotactic cytokines of approximately 8–10 kDa in size, which bind to specific chemokine receptors to induce leucocyte movement. Herein, the scientific literature investigating the role of chemokines in the propagation of immune responses against key protist infections will be reviewed, focussing onPlasmodiumspecies,Toxoplasma gondii, Leishmaniaspecies andCryptosporidiumspecies. Interestingly, many studies find that chemokines can in fact, promote parasite survival in the host, by drawing in leucocytes for spread and further replication. Recent developments in drug targeting against chemokine receptors highlights the need for further understanding of the role played by these proteins and their receptors in many different diseases.
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19
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Abstract
Naturally acquired immunity to the blood-stage of the malaria parasite develops slowly in areas of high endemicity, but is not sterilizing. It manifests as a reduction in parasite density and clinical symptoms. Immunity as a result of blood-stage vaccination has not yet been achieved in humans, although there are many animal models where vaccination has been successful. The development of a blood-stage vaccine has been complicated by a number of factors including limited knowledge of human-parasite interactions and which antigens and immune responses are critical for protection. Opinion is divided as to whether this vaccine should aim to accelerate the acquisition of responses acquired following natural exposure, or whether it should induce a different response. Animal and experimental human models suggest that cell-mediated immune responses can control parasite growth, but these responses can also contribute to significant immunopathology if unregulated. They are largely ignored in most blood-stage malaria vaccine development strategies. Here, we discuss key observations relating to cell-mediated immune responses in the context of experimental human systems and field studies involving naturally exposed individuals and how this may inform the development of a blood-stage malaria vaccine.
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20
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Hu Y, Cui Q, Luo C, Luo Y, Shi J, Huang H. A promising sword of tomorrow: Human γδ T cell strategies reconcile allo-HSCT complications. Blood Rev 2015; 30:179-88. [PMID: 26654098 DOI: 10.1016/j.blre.2015.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/06/2015] [Accepted: 11/20/2015] [Indexed: 12/15/2022]
Abstract
Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is potentially a curative therapeutic option for hematological malignancies. In clinical practice, transplantation associated complications greatly affected the final therapeutical outcomes. Currently, primary disease relapse, graft-versus-host disease (GVHD) and infections remain the three leading causes of a high morbidity and mortality in allo-HSCT patients. Various strategies have been investigated in the past several decades including human γδ T cell-based therapeutical regimens. In different microenvironments, human γδ T cells assume features reminiscent of classical Th1, Th2, Th17, NKT and regulatory T cells, showing diverse biological functions. The cytotoxic γδ T cells could be utilized to target relapsed malignancies, and recently regulatory γδ T cells are defined as a novel implement for GVHD management. In addition, human γδ Τ cells facilitate control of post-transplantation infections and participate in tissue regeneration and wound healing processes. These features potentiate γδ T cells a versatile therapeutical agent to target transplantation associated complications. This review focuses on insights of applicable potentials of human γδ T cells reconciling complications associated with allo-HSCT. We believe an improved understanding of pertinent γδ T cell functions would be further exploited in the design of innovative immunotherapeutic approaches in allo-HSCT, to reduce mortality and morbidity, as well as improve quality of life for patients after transplantation.
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Affiliation(s)
- Yongxian Hu
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China.
| | - Qu Cui
- Department of Hematology, Beijing Tiantan Hospital, Capital Medical University, 6 Tiantan Xili, Dongcheng District, Beijing 100050, China.
| | - Chao Luo
- Department of Hematology, Jinhua Central Hospital, No. 351 Mingyue Road, Jinhua 312000, China.
| | - Yi Luo
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China
| | - Jimin Shi
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China
| | - He Huang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China.
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21
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Stegmann KA, De Souza JB, Riley EM. IL-18-induced expression of high-affinity IL-2R on murine NK cells is essential for NK-cell IFN-γ production during murine Plasmodium yoelii infection. Eur J Immunol 2015; 45:3431-40. [PMID: 26420375 PMCID: PMC4982096 DOI: 10.1002/eji.201546018] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 08/19/2015] [Accepted: 09/23/2015] [Indexed: 12/25/2022]
Abstract
Early production of pro‐inflammatory cytokines, including IFN‐γ, is essential for control of blood‐stage malaria infections. We have shown that IFN‐γ production can be induced among human natural killer (NK) cells by coculture with Plasmodium falciparum infected erythrocytes, but the importance of this response is unclear. To further explore the role of NK cells during malaria infection, we have characterized the NK‐cell response of C57BL/6 mice during lethal (PyYM) or nonlethal (Py17XNL) P. yoelii infection. Ex vivo flow cytometry revealed that NK cells are activated within 24 h of Py17XNL blood‐stage infection, expressing CD25 and producing IFN‐γ; this response was blunted and delayed during PyYM infection. CD25 expression and IFN‐γ production were highly correlated, suggesting a causal relationship between the two responses. Subsequent in vitro experiments revealed that IL‐18 signaling is essential for induction of CD25 and synergizes with IL‐12 to enhance CD25 expression on splenic NK cells. In accordance with this, Py17XNL‐infected erythrocytes induced NK‐cell CD25 expression and IFN‐γ production in a manner that is completely IL‐18‐ and partially IL‐12‐dependent, and IFN‐γ production is enhanced by IL‐2. These data suggest that IL‐2 signaling via CD25 amplifies IL‐18‐ and IL‐12‐mediated NK‐cell activation during malaria infection.
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Affiliation(s)
- Kerstin A Stegmann
- Faculty of Infectious and Tropical Diseases, Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK
| | - J Brian De Souza
- Faculty of Infectious and Tropical Diseases, Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK.,Division of Infection and Immunity, University College London, London, UK
| | - Eleanor M Riley
- Faculty of Infectious and Tropical Diseases, Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK
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22
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BAKIR H, YONES D, GALAL L, HUSEEIN E. Resistance and Susceptibility to Malarial Infection: A Host Defense Strategy against Malaria. IRANIAN JOURNAL OF PARASITOLOGY 2015; 10:638-47. [PMID: 26811732 PMCID: PMC4724842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 10/21/2015] [Indexed: 10/25/2022]
Abstract
BACKGROUND In an effort to understand what limits the virulence of malaria parasites in relation to the host genetic and immunogenic background, we investigated the possibility that the parasite and host genotype crossover interactions constrain virulence. METHODS Two groups of mice from different genotypes were used (C57BL/6 (B6) and DBA/2 mice). The mice were infected with a virulent parasite line Plasmodium yoelii 17XL (P. yoelii 17XL). Parasitemia, hematocrit value and lymphocytes yielded by livers and spleens were evaluated. Fluorescence Activated Cell Sorting (FACS) analysis illustrated phenotypic characterization of lymphocytes. RESULTS Infection with P. yoelii 17XL did not result in the death of DBA/2 mice. In contrast, B6 mice developed significantly high parasitemia and succumbed to death. Using (FACS) analysis, DBA/2 mice were found to experience a marked expansion of interleukin (IL)-2Rβ(+) CD3(int) cells and γδ T cells in the liver, especially in the recovery phase. The expansion of unconventional T cells (i.e. B220(+) T cells) was also marked in DBA/2 mice. CONCLUSION The outcome of murine malaria infections depends on the dynamic interplay between the immune-mediator and the genotype of the host.
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Affiliation(s)
- Hanaa BAKIR
- Department of Parasitology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Doaa YONES
- Department of Parasitology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Lamia GALAL
- Department of Parasitology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Enas HUSEEIN
- Department of Parasitology, Faculty of Medicine, Assiut University, Assiut, Egypt
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23
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Eriksson EM, Schofield L. Dysfunctional γδ T cells: a contributing factor for clinical tolerance to malaria? ANNALS OF TRANSLATIONAL MEDICINE 2015; 3:S34. [PMID: 26046081 DOI: 10.3978/j.issn.2305-5839.2015.03.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 02/18/2015] [Indexed: 11/14/2022]
Affiliation(s)
- Emily M Eriksson
- 1 Walter and Eliza Hall Institute of Medical Science and University of Melbourne, Department of Medical Biology, VIC 3052, Australia ; 2 Australian Institute of Tropical Health and Medicine, James Cook University, Queensland 4811, Australia
| | - Louis Schofield
- 1 Walter and Eliza Hall Institute of Medical Science and University of Melbourne, Department of Medical Biology, VIC 3052, Australia ; 2 Australian Institute of Tropical Health and Medicine, James Cook University, Queensland 4811, Australia
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24
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Divan A, Budd RC, Tobin RP, Newell-Rogers MK. γδ T Cells and dendritic cells in refractory Lyme arthritis. J Leukoc Biol 2015; 97:653-63. [PMID: 25605869 DOI: 10.1189/jlb.2ru0714-343rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Lyme disease is a multisystem infection transmitted by tick vectors with an incidence of up to 300,000 individuals/yr in the United States. The primary treatments are oral or i.v. antibiotics. Despite treatment, some individuals do not recover and have prolonged symptoms affecting multiple organs, including the nervous system and connective tissues. Inflammatory arthritis is a common symptom associated with Lyme pathology. In the past decades, γδ T cells have emerged as candidates that contribute to the transition from innate to adaptive responses. These cells are also differentially regulated within the synovia of patients affected by RLA. Here, we review and discuss potential cellular mechanisms involving γδ T cells and DCs in RLA. TLR signaling and antigen processing and presentation will be the key concepts that we review in aid of understanding the impact of γδ T cells in RLA.
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Affiliation(s)
- Ali Divan
- *Texas A&M Health Science, Temple, Texas, USA; and University of Vermont, Burlington, Vermont, USA
| | - Ralph C Budd
- *Texas A&M Health Science, Temple, Texas, USA; and University of Vermont, Burlington, Vermont, USA
| | - Richard P Tobin
- *Texas A&M Health Science, Temple, Texas, USA; and University of Vermont, Burlington, Vermont, USA
| | - M Karen Newell-Rogers
- *Texas A&M Health Science, Temple, Texas, USA; and University of Vermont, Burlington, Vermont, USA
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25
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The protective effect of CD40 ligand-CD40 signalling is limited during the early phase of Plasmodium infection. FEBS Lett 2014; 588:2147-53. [PMID: 24815981 DOI: 10.1016/j.febslet.2014.04.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 04/16/2014] [Accepted: 04/22/2014] [Indexed: 01/30/2023]
Abstract
γδ T cells are essential for eliminating Plasmodium berghei XAT. Because administration of the agonistic anti-CD40 antibody can induce elimination of P. berghei XAT parasites in γδ T cell-deficient mice, we considered that γδ T cells might activate dendritic cells via CD40 signalling during infection. Here we report that administration of the anti-CD40 antibody to γδ T cell-deficient mice 3-10 days post-P. berghei XAT infection could eliminate the parasites. Our data suggest that dendritic cell activation via γδ T cells expressing CD40 ligand is critical during the early phase of infection.
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Abstract
Plasmodium falciparum malaria is responsible for over 250 million clinical cases every year worldwide. Severe malaria cases might present with a range of disease syndromes including acute respiratory distress, metabolic acidosis, hypoglycaemia, renal failure, anaemia, pulmonary oedema, cerebral malaria (CM) and placental malaria (PM) in pregnant women. Two main determinants of severe malaria have been identified: sequestration of parasitized red blood cells and strong pro-inflammatory responses. Increasing evidence from human studies and malaria infection animal models revealed the presence of host leucocytes at the site of parasite sequestration in brain blood vessels as well as placental tissue in complicated malaria cases. These observations suggested that apart from secreting cytokines, leucocytes might also contribute to disease by migrating to the site of parasite sequestration thereby exacerbating organ-specific inflammation. This evidence attracted substantial interest in identifying trafficking pathways by which inflammatory leucocytes are recruited to target organs during severe malaria syndromes. Chemo-attractant cytokines or chemokines are the key regulators of leucocyte trafficking and their potential contribution to disease has recently received considerable attention. This review summarizes the main findings to date, investigating the role of chemokines in severe malaria and the implication of these responses for the induction of pathogenesis and immunity to infection.
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Inoue SI, Niikura M, Mineo S, Kobayashi F. Roles of IFN-γ and γδ T Cells in Protective Immunity Against Blood-Stage Malaria. Front Immunol 2013; 4:258. [PMID: 24009610 PMCID: PMC3756480 DOI: 10.3389/fimmu.2013.00258] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 08/15/2013] [Indexed: 01/10/2023] Open
Abstract
Malaria is caused by infection with Plasmodium parasites. Various studies with knockout mice have indicated that IFN-γ plays essential roles in protective immunity against blood-stage Plasmodium infection. However, after Plasmodium infection, increased IFN-γ production by various types of cells is involved not only in protective immunity, but also in immunopathology. Recent reports have shown that IFN-γ acts as a pro-inflammatory cytokine to induce not only the activation of macrophages, but also the generation of uncommon myelolymphoid progenitor cells after Plasmodium infection. However, the effects of IFN-γ on hematopoietic stem cells and progenitor cells are unclear. Therefore, the regulation of hematopoiesis by IFN-γ during Plasmodium infection remains to be clarified. Although there are conflicting reports concerning the significance of γδ T cells in protective immunity against Plasmodium infection, γδ T cells may respond to infection and produce IFN-γ as innate immune cells in the early phase of blood-stage malaria. Our recent studies have shown that γδ T cells express CD40 ligand and produce IFN-γ after Plasmodium infection, resulting in the enhancement of dendritic cell activation as part of the immune response to eliminate Plasmodium parasites. These data suggest that the function of γδ T cells is similar to that of NK cells. Although several reports suggest that γδ T cells have the potential to act as memory cells for various infections, it remains to be determined whether memory γδ T cells are generated by Plasmodium infection and whether memory γδ T cells can contribute to the host defense against re-infection with Plasmodium. Here, we summarize and discuss the effects of IFN-γ and the various functions of γδ T cells in blood-stage Plasmodium infection.
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Affiliation(s)
- Shin-Ichi Inoue
- Department of Infectious Diseases, Kyorin University School of Medicine, Mitaka , Tokyo , Japan
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28
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Abstract
γδ-T cells represent a small population of immune cells, but play an indispensable role in host defenses against exogenous pathogens, immune surveillance of endogenous pathogenesis and even homeostasis of the immune system. Activation and expansion of γδ-T cells are generally observed in diverse human infectious diseases and correlate with their progression and prognosis. γδ-T cells have both 'innate' and 'adaptive' characteristics in the immune response, and their anti-infection activities are mediated by multiple pathways that are under elaborate regulation by other immune components. In this review, we summarize the current state of the literature and the recent advancements in γδ-T cell-mediated immune responses against common human infectious pathogens. Although further investigation is needed to improve our understanding of the characteristics of different γδ-T cell subpopulations under specific conditions, γδ-T cell-based therapy has great potential for the treatment of infectious diseases.
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Grangeiro de Carvalho E, Bonin M, Kremsner PG, Kun JFJ. Plasmodium falciparum-infected erythrocytes and IL-12/IL-18 induce diverse transcriptomes in human NK cells: IFN-α/β pathway versus TREM signaling. PLoS One 2011; 6:e24963. [PMID: 21949811 PMCID: PMC3174986 DOI: 10.1371/journal.pone.0024963] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 08/24/2011] [Indexed: 11/18/2022] Open
Abstract
The protective immunity of natural killer (NK) cells against malarial infections is thought to be due to early production of type II interferon (IFN) and possibly direct NK cell cytotoxicity. To better understand this mechanism, a microarray analysis was conducted on NK cells from healthy donors PBMCs that were co-cultured with P. falciparum 3D7-infected erythrocytes. A very similar pattern of gene expression was observed among all donors for each treatment in three replicas. Parasites particularly modulated genes involved in IFN-α/β signaling as well as molecules involved in the activation of interferon regulatory factors, pathways known to play a role in the antimicrobial immune response. This pattern of transcription was entirely different from that shown by NK cells treated with IL-12 and IL-18, in which IFN-γ- and TREM-1-related genes were over-expressed. These results suggest that P. falciparum parasites and the cytokines IL-12 and IL-18 have diverse imprints on the transcriptome of human primary NK cells. IFN-α-related genes are the prominent molecules induced by parasites on NK cells and arise as candidate biomarkers that merit to be further investigated as potential new tools in malaria control.
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MESH Headings
- Biomarkers/metabolism
- Blotting, Western
- Computational Biology
- Cytokines/genetics
- Cytokines/metabolism
- Erythrocytes/immunology
- Erythrocytes/parasitology
- Flow Cytometry
- Gene Expression Profiling
- Humans
- Interferon-alpha/genetics
- Interferon-alpha/metabolism
- Interferon-gamma/genetics
- Interferon-gamma/metabolism
- Interleukin-12/pharmacology
- Interleukin-18/pharmacology
- Killer Cells, Natural/drug effects
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/parasitology
- Lymphocyte Activation
- Malaria, Falciparum/immunology
- Malaria, Falciparum/metabolism
- Malaria, Falciparum/parasitology
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Oligonucleotide Array Sequence Analysis
- Plasmodium falciparum/genetics
- Plasmodium falciparum/immunology
- RNA, Messenger/genetics
- Real-Time Polymerase Chain Reaction
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- Signal Transduction
- Triggering Receptor Expressed on Myeloid Cells-1
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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] [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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31
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Harnessing immune responses against Plasmodium for rational vaccine design. Trends Parasitol 2011; 27:274-83. [PMID: 21531627 DOI: 10.1016/j.pt.2011.01.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Revised: 01/11/2011] [Accepted: 01/12/2011] [Indexed: 01/06/2023]
Abstract
In recent years, groundbreaking advances have been made in understanding the biology of and immune mechanisms against the Plasmodium spp. parasite, the causative agent of malaria. Novel features of the Plasmodium life cycle have been unravelled and immune mechanisms, which take place during both infection and immunization, have been dissected. We have undoubtedly enhanced our knowledge, but the question now is how to use this information to manipulate immune responses against Plasmodium and to develop an efficacious malaria vaccine. In this review, we discuss the latest developments in the field and speculate on how immune responses against Plasmodium could be harnessed for rational vaccine design and application.
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