scholarly journals CD4+ T cells are trigger and target of the glucocorticoid response that prevents lethal immunopathology in toxoplasma infection

2013 ◽  
Vol 210 (10) ◽  
pp. 1919-1927 ◽  
Author(s):  
David G. Kugler ◽  
Paul R. Mittelstadt ◽  
Jonathan D. Ashwell ◽  
Alan Sher ◽  
Dragana Jankovic

Synthetic glucocorticoids (GCs) are commonly used in the treatment of inflammatory diseases, but the role of endogenous GCs in the regulation of host-protective immune responses is poorly understood. Here we show that GCs are induced during acute Toxoplasma gondii infection and directly control the T cell response to the parasite. When infected with toxoplasma, mice that selectively lack GC receptor (GR) expression in T cells (GRlck-Cre) rapidly succumb to infection despite displaying parasite burdens indistinguishable from control animals and unaltered levels of the innate cytokines IL-12 and IL-27. Mortality in the GRlck-Cre mice was associated with immunopathology and hyperactive Th1 cell function as revealed by enhanced IFN-γ and TNF production in vivo. Unexpectedly, these CD4+ T lymphocytes also overexpressed IL-10. Importantly, CD4+ T cell depletion in wild-type or GRlck-Cre mice led to ablation of the GC response to infection. Moreover, in toxoplasma-infected RAG−/− animals, adoptive transfer of CD4+ T lymphocytes was required for GC induction. These findings establish a novel IL-10–independent immunomodulatory circuit in which CD4+ T cells trigger a GC response that in turn dampens their own effector function. In the case of T. gondii infection, this self-regulatory pathway is critical for preventing collateral tissue damage and promoting host survival.

2021 ◽  
Vol 118 (37) ◽  
pp. e2103444118
Author(s):  
Felipe Valença-Pereira ◽  
Qian Fang ◽  
Isabelle J. Marié ◽  
Emily L. Giddings ◽  
Karen A. Fortner ◽  
...  

Interleukin 6 (IL-6) is known to regulate the CD4 T cell function by inducing gene expression of a number of cytokines through activation of Stat3 transcription factor. Here, we reveal that IL-6 strengthens the mechanics of CD4 T cells. The presence of IL-6 during activation of mouse and human CD4 T cells enhances their motility (random walk and exploratory spread), resulting in an increase in travel distance and higher velocity. This is an intrinsic effect of IL-6 on CD4 T-cell fitness that involves an increase in mitochondrial Ca2+. Although Stat3 transcriptional activity is dispensable for this process, IL-6 uses mitochondrial Stat3 to enhance mitochondrial Ca2+-mediated motility of CD4 T cells. Thus, through a noncanonical pathway, IL-6 can improve competitive fitness of CD4 T cells by facilitating cell motility. These results could lead to alternative therapeutic strategies for inflammatory diseases in which IL-6 plays a pathogenic role.


2007 ◽  
Vol 204 (3) ◽  
pp. 489-495 ◽  
Author(s):  
Tim Worbs ◽  
Thorsten R. Mempel ◽  
Jasmin Bölter ◽  
Ulrich H. von Andrian ◽  
Reinhold Förster

In contrast to lymphocyte homing, little is known about molecular cues controlling the motility of lymphocytes within lymphoid organs. Applying intravital two-photon microscopy, we demonstrate that chemokine receptor CCR7 signaling enhances the intranodal motility of CD4+ T cells. Compared to wild-type (WT) cells, the average velocity and mean motility coefficient of adoptively transferred CCR7-deficient CD4+ T lymphocytes in T cell areas of WT recipients were reduced by 33 and 55%, respectively. Both parameters were comparably reduced for WT T lymphocytes migrating in T cell areas of plt/plt mice lacking CCR7 ligands. Importantly, systemic application of the CCR7 ligand CCL21 was sufficient to rescue the motility of WT T lymphocytes inside T cell areas of plt/plt recipients. Comparing the movement behavior of T cells in subcapsular areas that are devoid of detectable amounts of CCR7 ligands even in WT mice, we failed to reveal any differences between WT and plt/plt recipients. Furthermore, in both WT and plt/plt recipients, highly motile T cells rapidly accumulated in the subcapsular region after subcutaneous injection of the CCR7 ligand CCL19. Collectively, these data identify CCR7 and its ligands as important chemokinetic factors stimulating the basal motility of CD4+ T cells inside lymph nodes in vivo.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3110-3110
Author(s):  
Erwan R. Piriou ◽  
Christine Jansen ◽  
Karel van Dort ◽  
Iris De Cuyper ◽  
Nening M. Nanlohy ◽  
...  

Abstract Objective: EBV-specific CD8+ T cells have been extensively studied in various settings, and appear to play a major role in the control of EBV-related malignancies. In contrast, it is still unclear whether EBV-specific CD4+ T cells play a role in vivo. To study this question, an assay was developed to measure the CD4+ T-cell response towards two EBV antigens, in both healthy (n=14) and HIV-infected subjects (n=23). In addition, both HAART-treated (n=12) and untreated HIV+ individuals (n=14) - including progressors to EBV-related lymphoma - were studied longitudinally. Methods: EBV-specific CD4+ T cells were stimulated with peptide pools from latent protein EBNA1 and lytic protein BZLF1, and detected by measurement of IFNg-production. Results: After direct ex vivo stimulation, EBNA1 or BZLF1-specific IFNg- (and/or IL2) producing CD4+ T cell numbers were low, and measurable in less than half of the subjects studied (either HIV- and HIV+). Therefore, PBMC were cultured for 12 days in the presence of peptides and IL2 (from day 3), and then restimulated with peptides, allowing specific and reproducible expansion of EBV-specific CD4+ T cells, independent of HLA type and ex vivo antigen processing. Interestingly, numbers of EBV-specific CD4+ T cells inversely correlated with EBV viral load, implying an important role for EBV-specific CD4+ T cells in the control of EBV in vivo. Untreated HIV-infected individuals had a lower CD4+ T cell response to EBNA1 and BZLF1 as compared to healthy EBV carriers and HAART-treated HIV+ subjects. In longitudinal samples, EBNA1-specific, but not BZLF1-specific T-cell numbers increased after HAART, while EBV load was not affected by treatment. In all the progressors to EBV-related lymphoma, EBV-specific CD4+ T cells were lost at least 24 months before lymphoma diagnosis. Conclusions: Both cross-sectional and longitudinal data suggest an important role for EBV-specific CD4+ T cells in the control of EBV-related malignancies. Furthermore, it seems that HAART treatment leads to recovery of EBNA1-specific, but not BZLF1-specific CD4+ T-cell responses, implying changes in the latency pattern of EBV, despite an unaltered cell-associated EBV DNA load. Thus, early HAART treatment might prevent loss of specific CD4+ T-cell help and progression to NHL.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 588-588
Author(s):  
Karrune Woan ◽  
Fengdong Cheng ◽  
Hongwei Wang ◽  
Jennifer Rock-Klotz ◽  
Zi Wang ◽  
...  

Abstract Abstract 588 We recently defined a novel role of histone deacetylase 11 (HDAC11), the newest member of the HDAC family, as a negative regulator of IL-10 gene transcription in antigen-presenting cells (APCs).1 To better understand the role of HDAC11 gene expression in immune cells in vivo, we have utilized a BAC (Bacterial artificial chromosome) transgenic mouse in which the EGFP reporter gene was inserted downstream of the HDAC11 promoter region but immediately upstream of the HDAC11 coding sequence (TgHDAC11-EGFP mice).2 In the steady-state, macrophages and B-cells isolated from spleen of TgHDAC11-EGFP mice express low levels of HDAC11 as evidenced by a slight shift in EGFP fluorescence from background. In sharp contrast, we identified a discrete population (11.9%) of T-cells over-expressing HDAC11 as demonstrated both by flow cytometry for EGFP and by qRT-PCR for HDAC11, a majority of which were CD4+ T-cells. Sorting of this EGFP+, CD4+ T-cell population confirmed that the increased EGFP expression correlated with an increased HDAC11mRNA expression. Reminiscent of our prior data in APCs, the increased expression of HDAC11 in T-cells was also inversely correlated with IL-10mRNA expression. Further analyses revealed that in the absence of any stimulation or T-cell polarizing conditions, this EGFP positive population expressed significantly elevated levels of ROR-γt and IL-17 mRNA, markers specific for the TH17 subpopulation. Polarization of wild type CD4+ T-cells into functional TH17 cells was associated with reduction of HDAC11 expression, suggesting a potential role for HDAC11 in regulating T-cell function and/or activation, in particular within the TH17 subset. Further support for this regulatory role of HDAC11 has been provided by our additional findings that T-cells devoid of HDAC11 are indeed hyper-reactive in vitro and in in vivo models. 1. Villagra A, et al. Nat Immunol. 2009 Jan;10(1):92-100. 2. Gong S, et al. Nature. 2003 Oct 30;425(6961):917-25. Disclosures: No relevant conflicts of interest to declare.


2003 ◽  
Vol 197 (7) ◽  
pp. 861-874 ◽  
Author(s):  
Ye Zheng ◽  
Monika Vig ◽  
Jesse Lyons ◽  
Luk Van Parijs ◽  
Amer A. Beg

Signaling pathways involved in regulating T cell proliferation and survival are not well understood. Here we have investigated a possible role of the nuclear factor (NF)-κB pathway in regulating mature T cell function by using CD4+ T cells from p50−/− cRel−/− mice, which exhibit virtually no inducible κB site binding activity. Studies with these mice indicate an essential role of T cell receptor (TCR)-induced NF-κB in regulating interleukin (IL)-2 expression, cell cycle entry, and survival of T cells. Our results further indicate that NF-κB regulates TCR-induced expression of antiapoptotic Bcl-2 family members. Strikingly, retroviral transduction of CD4+ T cells with the NF-κB–inducing IκB kinase β showed that NF-κB activation is not only necessary but also sufficient for T cell survival. In contrast, our results indicate a lack of involvement of NF-κB in both IL-2 and Akt-induced survival pathways. In vivo, p50−/− cRel−/− mice showed impaired superantigen-induced T cell responses as well as decreased numbers of effector/memory and regulatory CD4+ T cells. These findings provide the first demonstration of a role for NF-κB proteins in regulating T cell function in vivo and establish a critically important function of NF-κB in TCR-induced regulation of survival.


2016 ◽  
Vol 130 (22) ◽  
pp. 2061-2071 ◽  
Author(s):  
Qing-Qing Wu ◽  
Yuan Yuan ◽  
Xiao-Han Jiang ◽  
Yang Xiao ◽  
Zheng Yang ◽  
...  

Global loss of OX40 aids in resisting pressure overload-induced cardiac remodelling. OX40 KO mice with reconstituted CD4+ T-lymphocytes presented deteriorated cardiac remodelling. OX40 alters the pathology of cardiac remodelling via the modulation of CD4+ T-cell function.


2010 ◽  
Vol 207 (9) ◽  
pp. 1891-1905 ◽  
Author(s):  
Magali Irla ◽  
Natalia Küpfer ◽  
Tobias Suter ◽  
Rami Lissilaa ◽  
Mahdia Benkhoucha ◽  
...  

Although plasmacytoid dendritic cells (pDCs) express major histocompatibility complex class II (MHCII) molecules, and can capture, process, and present antigens (Ags), direct demonstrations that they function as professional Ag-presenting cells (APCs) in vivo during ongoing immune responses remain lacking. We demonstrate that mice exhibiting a selective abrogation of MHCII expression by pDCs develop exacerbated experimental autoimmune encephalomyelitis (EAE) as a consequence of enhanced priming of encephalitogenic CD4+ T cell responses in secondary lymphoid tissues. After EAE induction, pDCs are recruited to lymph nodes and establish MHCII-dependent myelin-Ag–specific contacts with CD4+ T cells. These interactions promote the selective expansion of myelin-Ag–specific natural regulatory T cells that dampen the autoimmune T cell response. pDCs thus function as APCs during the course of EAE and confer a natural protection against autoimmune disease development that is mediated directly by their ability to present of Ags to CD4+ T cells in vivo.


Blood ◽  
2002 ◽  
Vol 99 (9) ◽  
pp. 3335-3341 ◽  
Author(s):  
Peter K. C. Goon ◽  
Emmanuel Hanon ◽  
Tadahiko Igakura ◽  
Yuetsu Tanaka ◽  
Jonathan N. Weber ◽  
...  

Abstract CD4+ T cells are critical for inducing and maintaining efficient humoral and cellular immune responses to pathogens. The CD4+ T-cell response in human T-lymphotropic virus 1 (HTLV-1) infection has not been studied in detail. However, CD4+ T cells have been shown to predominate in early lesions in HTLV-1–associated myelopathy/tropical spastic paraparesis (HAM/TSP). We present direct estimates of HTLV-1 Env- and Tax-specific CD4+ T-cell frequencies in patients infected with HTLV-1. We first showed that there was a strong bias toward the Th1 phenotype in these HTLV-1–specific CD4+ T cells in patients with HAM/TSP. We then demonstrated significantly higher frequencies of HTLV-1–specific Th1-type CD4+ T cells in HAM/TSP patients than in asymptomatic HTLV-1 carriers. The majority of these HTLV-1–specific CD4+ T cells did not express HTLV-1 Tax and were therefore unlikely to be infected by HTLV-1. High frequencies of activated HTLV-1–specific CD4+ T cells of the Th1 phenotype might contribute to the initiation or pathogenesis of HAM/TSP and other HTLV-1–associated inflammatory diseases.


2005 ◽  
Vol 201 (6) ◽  
pp. 845-851 ◽  
Author(s):  
Laura Haynes ◽  
Sheri M. Eaton ◽  
Eve M. Burns ◽  
Troy D. Randall ◽  
Susan L. Swain

Using a T cell receptor transgenic (TCR Tg) mouse model, we have shown that TCR Tg CD4 cells from aged mice retain a naive phenotype, but exhibit reduced proliferation and IL-2 production in response to the antigen compared with cells from young mice. We hypothesize that age-related decreases in T cell function may be partly related to the age of the T cells. Because thymic output is decreased with age, peripheral T cells in older individuals are likely to be older than those in younger individuals. To investigate this possibility, we have manipulated the age of CD4 T cells in the periphery of young and aged mice. The production of new T cells was induced by depleting peripheral CD4 T cells or by creating bone marrow chimeras. In both young and aged individuals where we induced the production of new T cells, these newly generated cells exhibited robust responses to antigen ex vivo and in vivo, exhibiting good expansion, IL-2 production, and cognate helper function. Our results suggest that age-related defects in response to antigenic stimulation, in part, are caused by the age of the CD4 T cells.


2010 ◽  
Vol 84 (20) ◽  
pp. 10501-10509 ◽  
Author(s):  
Jie Liu ◽  
Tracy J. Ruckwardt ◽  
Man Chen ◽  
John D. Nicewonger ◽  
Teresa R. Johnson ◽  
...  

ABSTRACT The role of epitope-specific regulatory CD4 T cells in modulating CD8 T-cell-mediated immunopathology during acute viral infection has not been well defined. In the murine model of respiratory syncytial virus (RSV) infection, CD8 T cells play an important role in both viral clearance and immunopathology. We have previously characterized two RSV epitope-specific CD4 T-cell responses with distinct phenotypic properties. One of them, the IAbM209-specific subset, constitutively expresses FoxP3 and modulates CD8 T-cell function in vitro. We show here that the IAbM209-specific CD4 T-cell response regulates CD8 T-cell function in vivo and is associated with diminished RSV-induced illness without affecting viral clearance at the site of infection. Achieving the optimal balance of regulatory and effector T-cell function is an important consideration for designing future vaccines.


Sign in / Sign up

Export Citation Format

Share Document