scholarly journals IRGM3 Contributes to Immunopathology and Is Required for Differentiation of Antigen-Specific Effector CD8+T Cells in Experimental Cerebral Malaria

2015 ◽  
Vol 83 (4) ◽  
pp. 1406-1417 ◽  
Author(s):  
Jintao Guo ◽  
James A. McQuillan ◽  
Belinda Yau ◽  
Gregory S. Tullo ◽  
Carole A. Long ◽  
...  
Keyword(s):  
T Cells ◽  
Cerebral Malaria ◽  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Type I ◽  
Experimental Cerebral Malaria ◽  
Content Type ◽  
Cytokines And Chemokines ◽  
Specific Effector ◽  
Ifn Γ

Gamma interferon (IFN-γ) drives antiparasite responses and immunopathology during infection withPlasmodiumspecies. Immunity-related GTPases (IRGs) are a class of IFN-γ-dependent proteins that are essential for cell autonomous immunity to numerous intracellular pathogens. However, it is currently unknown whether IRGs modulate responses during malaria. We have used thePlasmodium bergheiANKA (PbA) model in which mice develop experimental cerebral malaria (ECM) to study the roles of IRGM1 and IRGM3 in immunopathology. Induction of mRNA forIrgm1andIrgm3was found in the brains and spleens of infected mice at times of peak IFN-γ production.Irgm3−/−but notIrgm1−/−mice were completely protected from the development of ECM, and this protection was associated with the decreased induction of inflammatory cytokines, as well as decreased recruitment and activation of CD8+T cells within the brain. Although antigen-specific proliferation of transferred CD8+T cells was not diminished compared to that of wild-type recipients following PbA infection, T cells transferred intoIrgm3−/−recipients showed a striking impairment of effector differentiation. Decreased induction of several inflammatory cytokines and chemokines (interleukin-6, CCL2, CCL3, and CCL4), as well as enhanced mRNA expression of type-I IFNs, was found in the spleens ofIrgm3−/−mice at day 4 postinfection. Together, these data suggest that protection from ECM pathology inIrgm3−/−mice occurs due to impaired generation of CD8+effector function. This defect is nonintrinsic to CD8+T cells. Instead, diminished T cell responses most likely result from defective initiation of inflammatory responses in myeloid cells.

scholarly journals IFN-γ–Producing CD4+ T Cells Promote Experimental Cerebral Malaria by Modulating CD8+ T Cell Accumulation within the Brain

2012 ◽  
Vol 189 (2) ◽  
pp. 968-979 ◽  
Author(s):  
Ana Villegas-Mendez ◽  
Rachel Greig ◽  
Tovah N. Shaw ◽  
J. Brian de Souza ◽  
Emily Gwyer Findlay ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cerebral Malaria ◽  
Cd4 T Cells ◽  
Cd8 T Cell ◽  
Experimental Cerebral Malaria ◽  
Cell Accumulation ◽  
Ifn Γ ◽  
The Brain

scholarly journals Early Induction of Interleukin-10 Limits Antigen-Specific CD4+T Cell Expansion, Function, and Secondary Recall Responses during Persistent Phagosomal Infection

2014 ◽  
Vol 82 (10) ◽  
pp. 4092-4103 ◽  
Author(s):  
Abinav Kumar Singh ◽  
Nagaraja R. Thirumalapura
Keyword(s):  
T Cells ◽  
T Cell ◽  
Functional Status ◽  
Persistent Infection ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Interleukin 10 ◽  
Host Cells ◽  
Content Type ◽  
Ifn Γ

ABSTRACTDiverse pathogens have evolved to survive and replicate in the endosomes or phagosomes of the host cells and establish persistent infection. Ehrlichiae are Gram-negative, intracellular bacteria that are transmitted by ticks. Ehrlichiae reside in the endosomes of the host phagocytic or endothelial cells and establish persistent infection in their vertebrate reservoir hosts. CD4+T cells play a critical role in protection against phagosomal infections. In the present study, we investigated the expansion, maintenance, and functional status of antigen-specific CD4+T cells during persistentEhrlichia murisinfection in wild-type and interleukin-10 (IL-10)-deficient mice. Our study indicated that early induction of IL-10 led to reduced inflammatory responses and impaired bacterial clearance during persistentEhrlichiainfection. Notably, we demonstrated that the functional production of gamma interferon (IFN-γ) by antigen-specific CD4+T cells maintained during a persistent phagosomal infection progressively deteriorates. The functional loss of IFN-γ production by antigen-specific CD4+T cells was reversed in the absence of IL-10. Furthermore, we demonstrated that transient blockade of IL-10 receptor during the T cell priming phase early in infection was sufficient to enhance the magnitude and the functional capacity of antigen-specific effector and memory CD4+T cells, which translated into an enhanced recall response. Our findings provide new insights into the functional status of antigen-specific CD4+T cells maintained during persistent phagosomal infection. The study supports the concept that a better understanding of the factors that influence the priming and differentiation of CD4+T cells may provide a basis to induce a protective immune response against persistent infections.

Up-regulated expression in nonhematopoietic tissues of the BCL2A1-derived minor histocompatibility antigens in response to inflammatory cytokines: relevance for allogeneic immunotherapy of leukemia

Blood ◽  
2005 ◽  
Vol 106 (12) ◽  
pp. 3955-3957 ◽  
Author(s):  
Freke M. Kloosterboer ◽  
Simone A. P. van Luxemburg-Heijs ◽  
Ronald A. van Soest ◽  
H. M. Esther van Egmond ◽  
Roel Willemze ◽  
...  
Keyword(s):  
T Cells ◽  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Interferon Γ ◽  
Hematopoietic Tissue ◽  
Histocompatibility Antigens ◽  
Minor Histocompatibility Antigens ◽  
Tnf Α ◽  
Relative Specificity ◽  
Ifn Γ

T cells directed against hematopoietic-restricted minor histocompatibility antigens (mHags) may mediate graft-versus-leukemia (GVL) reactivity without graft-versus-host disease (GVHD). Recently, the HLA-A24–restricted mHag ACC-1 and the HLA-B44–restricted mHag ACC-2 encoded by separate polymorphisms within the BCL2A1 gene were characterized. Hematopoietic-restricted expression was suggested for these mHags. We demonstrate BCL2-related protein A1 (BCL2A1) mRNA expression in mesenchymal stromal cells (MSCs) that was up-regulated by the inflammatory cytokines tumor necrosis factor α (TNF-α) and/or interferon γ (IFN-γ). Analysis of cytotoxicity and IFN-γ production illustrated that ACC-2–specific T cells did not recognize untreated MSCs or IFN-γ–treated MSCs but showed specific recognition and killing of MSCs treated with TNF-α plus IFN-γ. We hypothesize that under steady-state circumstances BCL2A1-specific T cells may exhibit relative specificity for hematopoietic tissue, but reactivity against nonhematopoietic cells may occur when inflammatory infiltrates are present. Thus, the role of BCL2A1-specific T cells in differential induction of GVL reactivity and GVHD may depend on the presence of inflammatory responses that may occur during GVHD.

scholarly journals Suppression of CD4+Effector Responses by Naturally Occurring CD4+CD25+Foxp3+Regulatory T Cells Contributes to Experimental Cerebral Malaria

2015 ◽  
Vol 84 (1) ◽  
pp. 329-338 ◽  
Author(s):  
Anne-Laurence Blanc ◽  
Tarun Keswani ◽  
Olivier Gorgette ◽  
Antonio Bandeira ◽  
Bernard Malissen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
Cerebral Malaria ◽  
T Cell Response ◽  
Experimental Cerebral Malaria ◽  
Content Type ◽  
Naturally Occurring ◽  
Cell Enrichment

The role of naturally occurring CD4+CD25+Foxp3+regulatory T cells (nTreg) in the pathogenesis of cerebral malaria (CM), which involves both pathogenic T cell responses and parasite sequestration in the brain, is still unclear. To assess the contribution and dynamics of nTreg during the neuropathogenesis, we unbalanced the ratio between nTreg and naive CD4+T cells in an attenuated model ofPlasmodium bergheiANKA-induced experimental CM (ECM) by using a selective cell enrichment strategy. We found that nTreg adoptive transfer accelerated the onset and increased the severity of CM in syngeneic C57BL/6 (B6)P. bergheiANKA-infected mice without affecting the level of parasitemia. In contrast, naive CD4+T cell enrichment prevented CM and promoted parasite clearance. Furthermore, early during the infection nTreg expanded in the spleen but did not efficiently migrate to the site of neuroinflammation, suggesting that nTreg exert their pathogenic action early in the spleen by suppressing the protective naive CD4+T cell response toP. bergheiANKA infectionin vivoin both CM-susceptible (B6) and CM-resistant (B6-CD4−/−) mice. However, their sole transfer was not sufficient to restore CM susceptibility in two CM-resistant congenic strains tested. Altogether, these results demonstrate that nTreg are activated and functional duringP. bergheiANKA infection and that they contribute to the pathogenesis of CM. They further suggest that nTreg may represent an early target for the modulation of the immune response to malaria.

scholarly journals γδ-T cells promote IFN-γ–dependent Plasmodium pathogenesis upon liver-stage infection

2019 ◽  
Vol 116 (20) ◽  
pp. 9979-9988 ◽  
Author(s):  
Julie C. Ribot ◽  
Rita Neres ◽  
Vanessa Zuzarte-Luís ◽  
Anita Q. Gomes ◽  
Liliana Mancio-Silva ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cerebral Malaria ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Γδ T Cells ◽  
Experimental Cerebral Malaria ◽  
Liver Stage ◽  
Ifn Γ ◽  
Stage Infection

Cerebral malaria (CM) is a major cause of death due to Plasmodium infection. Both parasite and host factors contribute to the onset of CM, but the precise cellular and molecular mechanisms that contribute to its pathogenesis remain poorly characterized. Unlike conventional αβ-T cells, previous studies on murine γδ-T cells failed to identify a nonredundant role for this T cell subset in experimental cerebral malaria (ECM). Here we show that mice lacking γδ-T cells are resistant to ECM when infected with Plasmodium berghei ANKA sporozoites, the liver-infective form of the parasite and the natural route of infection, in contrast with their susceptible phenotype if challenged with P. berghei ANKA-infected red blood cells that bypass the liver stage of infection. Strikingly, the presence of γδ-T cells enhanced the expression of Plasmodium immunogenic factors and exacerbated subsequent systemic and brain-infiltrating inflammatory αβ-T cell responses. These phenomena were dependent on the proinflammatory cytokine IFN-γ, which was required during liver stage for modulation of the parasite transcriptome, as well as for downstream immune-mediated pathology. Our work reveals an unanticipated critical role of γδ-T cells in the development of ECM upon Plasmodium liver-stage infection.

scholarly journals Damage to the Blood-Brain Barrier during Experimental Cerebral Malaria Results from Synergistic Effects of CD8+T Cells with Different Specificities

2014 ◽  
Vol 82 (11) ◽  
pp. 4854-4864 ◽  
Author(s):  
Chek Meng Poh ◽  
Shanshan W. Howland ◽  
Gijsbert M. Grotenbreg ◽  
Laurent Rénia
Keyword(s):  
T Cells ◽  
Cerebral Malaria ◽  
Blood Brain Barrier ◽  
Synergistic Effects ◽  
Brain Barrier ◽  
High Dose ◽  
Experimental Cerebral Malaria ◽  
Content Type ◽  
Blood Brain

ABSTRACTCD8+T cells play a pathogenic role in the development of murine experimental cerebral malaria (ECM) induced byPlasmodium bergheiANKA (PbA) infection in C57BL/6 mice. Only a limited number of CD8+epitopes have been described. Here, we report the identification of a new epitope from the bergheilysin protein recognized by PbA-specific CD8+T cells. Induction and functionality of these specific CD8+T cells were investigated in parallel with previously reported epitopes, using new tools such as tetramers and reporter cell lines that were developed for this study. We demonstrate that CD8+T cells of diverse specificities induced during PbA infection share many characteristics. They express cytolytic markers (gamma interferon [IFN-γ], granzyme B) and chemokine receptors (CXCR3, CCR5) and damage the blood-brain barrierin vivo. Our earlier finding that brain microvessels in mice infected with PbA, but not with non-ECM-causing strains, cross-presented a shared epitope was generalizable to these additional epitopes. Suppressing the induction of specific CD8+T cells through tolerization with a high-dose peptide injection was unable to confer protection against ECM, suggesting that CD8+T cells of other specificities participate in this process. The tools that we developed can be used to further investigate the heterogeneity of CD8+T cell responses that are involved in ECM.

scholarly journals Eosinophils Suppress the Migration of T Cells Into the Brain of Plasmodium berghei-Infected Ifnar1-/- Mice and Protect Them From Experimental Cerebral Malaria

2021 ◽  
Vol 12 ◽  
Author(s):  
Johanna F. Scheunemann ◽  
Julia J. Reichwald ◽  
Patricia Jebett Korir ◽  
Janina M. Kuehlwein ◽  
Lea-Marie Jenster ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cerebral Malaria ◽  
Plasmodium Berghei ◽  
T Cell Responses ◽  
Cytotoxic T Cell ◽  
Type I ◽  
Experimental Cerebral Malaria ◽  
Cell Responses ◽  
The Brain

Cerebral malaria is a potentially lethal disease, which is caused by excessive inflammatory responses to Plasmodium parasites. Here we use a newly developed transgenic Plasmodium berghei ANKA (PbAAma1OVA) parasite that can be used to study parasite-specific T cell responses. Our present study demonstrates that Ifnar1-/- mice, which lack type I interferon receptor-dependent signaling, are protected from experimental cerebral malaria (ECM) when infected with this novel parasite. Although CD8+ T cell responses generated in the spleen are essential for the development of ECM, we measured comparable parasite-specific cytotoxic T cell responses in ECM-protected Ifnar1-/- mice and wild type mice suffering from ECM. Importantly, CD8+ T cells were increased in the spleens of ECM-protected Ifnar1-/- mice and the blood-brain-barrier remained intact. This was associated with elevated splenic levels of CCL5, a T cell and eosinophil chemotactic chemokine, which was mainly produced by eosinophils, and an increase in eosinophil numbers. Depletion of eosinophils enhanced CD8+ T cell infiltration into the brain and increased ECM induction in PbAAma1OVA-infected Ifnar1-/- mice. However, eosinophil-depletion did not reduce the CD8+ T cell population in the spleen or reduce splenic CCL5 concentrations. Our study demonstrates that eosinophils impact CD8+ T cell migration and proliferation during PbAAma1OVA-infection in Ifnar1-/- mice and thereby are contributing to the protection from ECM.

scholarly journals ZBTB7B (ThPOK) Is Required for Pathogenesis of Cerebral Malaria and Protection against Pulmonary Tuberculosis

2019 ◽  
Vol 88 (2) ◽  
Author(s):  
James M. Kennedy ◽  
Anna Georges ◽  
Angelia V. Bassenden ◽  
Silvia M. Vidal ◽  
Albert M. Berghuis ◽  
...  
Keyword(s):  
T Cells ◽  
Dna Binding ◽  
Cerebral Malaria ◽  
Ex Vivo ◽  
Transcriptional Networks ◽  
Loss Of Function ◽  
Experimental Cerebral Malaria ◽  
Content Type ◽  
A Genome

ABSTRACT We used a genome-wide screen in N-ethyl-N-nitrosourea (ENU)-mutagenized mice to identify genes in which recessive loss-of-function mutations protect against pathological neuroinflammation. We identified an R367Q mutation in the ZBTB7B (ThPOK) protein in which homozygosity causes protection against experimental cerebral malaria (ECM) caused by infection with Plasmodium berghei ANKA. Zbtb7bR367Q homozygous mice show a defect in the lymphoid compartment expressed as severe reduction in the number of single-positive CD4 T cells in the thymus and in the periphery, reduced brain infiltration of proinflammatory leukocytes in P. berghei ANKA-infected mice, and reduced production of proinflammatory cytokines by primary T cells ex vivo and in vivo. Dampening of proinflammatory immune responses in Zbtb7bR367Q mice is concomitant to increased susceptibility to infection with avirulent (Mycobacterium bovis BCG) and virulent (Mycobacterium tuberculosis H37Rv) mycobacteria. The R367Q mutation maps to the first DNA-binding zinc finger domain of ThPOK and causes loss of base contact by R367 in the major groove of the DNA, which is predicted to impair DNA binding. Global immunoprecipitation of ThPOK-containing chromatin complexes coupled to DNA sequencing (ChIP-seq) identified transcriptional networks and candidate genes likely to play key roles in CD4+ CD8+ T cell development and in the expression of lineage-specific functions of these cells. This study highlights ThPOK as a global regulator of immune function in which alterations may affect normal responses to infectious and inflammatory stimuli.

scholarly journals CD8+ T Cells and IFN-γ Mediate the Time-Dependent Accumulation of Infected Red Blood Cells in Deep Organs during Experimental Cerebral Malaria

PLoS ONE ◽  
2011 ◽  
Vol 6 (4) ◽  
pp. e18720 ◽  
Author(s):  
Carla Claser ◽  
Benoît Malleret ◽  
Sin Yee Gun ◽  
Alicia Yoke Wei Wong ◽  
Zi Wei Chang ◽  
...  
Keyword(s):  
T Cells ◽  
Red Blood Cells ◽  
Cerebral Malaria ◽  
Cd8 T Cells ◽  
Blood Cells ◽  
Time Dependent ◽  
Experimental Cerebral Malaria ◽  
Ifn Γ

scholarly journals Toxoplasma gondii Upregulates Interleukin-12 To Prevent Plasmodium berghei-Induced Experimental Cerebral Malaria

2014 ◽  
Vol 82 (3) ◽  
pp. 1343-1353 ◽  
Author(s):  
Erik W. Settles ◽  
Lindsey A. Moser ◽  
Tajie H. Harris ◽  
Laura J. Knoll
Keyword(s):  
Toxoplasma Gondii ◽  
Cerebral Malaria ◽  
Plasmodium Berghei ◽  
Serum Levels ◽  
Interleukin 12 ◽  
Experimental Cerebral Malaria ◽  
Content Type ◽  
T Cell Infiltration ◽  
Ifn Γ ◽  
Deficient Mice

ABSTRACTA chronic infection with the parasiteToxoplasma gondiihas previously been shown to protect mice against subsequent viral, bacterial, or protozoal infections. Here we have shown that a chronicT. gondiiinfection can preventPlasmodium bergheiANKA-induced experimental cerebral malaria (ECM) in C57BL/6 mice. Treatment with solubleT. gondiiantigens (STAg) reduced parasite sequestration and T cell infiltration in the brains ofP. berghei-infected mice. Administration of STAg also preserved blood-brain barrier function, reduced ECM symptoms, and significantly decreased mortality. STAg treatment 24 h post-P. bergheiinfection led to a rapid increase in serum levels of interleukin 12 (IL-12) and gamma interferon (IFN-γ). By 5 days afterP. bergheiinfection, STAg-treated mice had reduced IFN-γ levels compared to those of mock-treated mice, suggesting that reductions in IFN-γ at the time of ECM onset protected against lethality. Using IL-10- and IL-12βR-deficient mice, we found that STAg-induced protection from ECM is IL-10 independent but IL-12 dependent. Treatment ofP. berghei-infected mice with recombinant IL-12 significantly decreased parasitemia and mortality. These data suggest that IL-12, either induced by STAg or injected as a recombinant protein, mediates protection from ECM-associated pathology potentially through early induction of IFN-γ and reduction in parasitemia. These results highlight the importance of early IL-12 induction in protection against ECM.

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