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Sample records for tregs cd8 tregs

  1. Microbiota-specific CD4CD8αα Tregs: role in intestinal immune homeostasis and implications for IBD

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    Guillaume eSARRABAYROUSE

    2015-10-01

    Full Text Available In studies in murine models, active suppression by IL-10-secreting Foxp3 regulatory T cells (Tregs has emerged as an essential mechanism in colon homeostasis. However, the role of the equivalent subset in humans remains unclear, leading to suggestions that other subsets and/or mechanisms may substitute for Foxp3 Tregs in the maintenance of colon homeostasis. We recently described a new subset of CD4CD8αα T cells reactive to the gut bacterium Faecalibacterium prausnitzii and endowed with regulatory/suppressive functions. This subset is abundant in the healthy colonic mucosa, but less common in that of patients with irritable bowel disease (IBD. We discuss here the physiological significance and potential role of these Tregs in preventing inflammation of the gut mucosa and the potential applications of these discoveries for IBD management.

  2. Ex Vivo Expanded Human Non-Cytotoxic CD8+CD45RClow/− Tregs Efficiently Delay Skin Graft Rejection and GVHD in Humanized Mice

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    Séverine Bézie

    2018-01-01

    Full Text Available Both CD4+ and CD8+ Tregs play a critical role in the control of immune responses and immune tolerance; however, our understanding of CD8+ Tregs is limited while they are particularly promising for therapeutic application. We report here existence of highly suppressive human CD8+CD45RClow/− Tregs expressing Foxp3 and producing IFNγ, IL-10, IL-34, and TGFβ to mediate their suppressive activity. We demonstrate that total CD8+CD45RClow/− Tregs can be efficiently expanded in the presence of anti-CD3/28 mAbs, high-dose IL-2 and IL-15 and that such expanded Tregs efficiently delay GVHD and human skin transplantation rejection in immune humanized mice. Robustly expanded CD8+ Tregs displayed a specific gene signature, upregulated cytokines and expansion in the presence of rapamycin greatly improved proliferation and suppression. We show that CD8+CD45RClow/− Tregs are equivalent to canonical CD4+CD25highCD127low/− Tregs for suppression of allogeneic immune responses in vitro. Altogether, our results open new perspectives to tolerogenic strategies in human solid organ transplantation and GVHD.

  3. CD4⁺ and CD8⁺ regulatory T cells (Tregs) are elevated and display an active phenotype in patients with chronic HCV mono-infection and HIV/HCV co-infection

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    Hartling, H J; Gaardbo, J C; Ronit, A

    2012-01-01

    The aim of this study was to examine regulatory T cells (Tregs) in peripheral blood and liver tissue in patients with chronic hepatitis C virus (HCV) mono-infection and in patients with HIV/HCV co-infection. In a cross-sectional study were included 51 patients with chronic HCV infection, 24...... patients with HIV/HCV co-infection and 24 healthy individuals. CD4⁺ and CD8Tregs were determined using flow cytometry. Fibrosis was examined by transient elastography. Inflammation, fibrosis and Tregs were determined in liver biopsies from 12 patients. Increased frequency of CD4⁺ and CD8Tregs was found...... in HIV/HCV co-infected patients [median: 6.4% (IQR: 5.7-6.9) and 1.0% (0.7-1.2), respectively] compared to HCV mono-infected patients [5.6% (4.2-6.3), P = 0.01 and 0.5% (0.3-0.7), P

  4. Transient Treg depletion enhances therapeutic anti‐cancer vaccination

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    Aston, Wayne J.; Chee, Jonathan; Khong, Andrea; Cleaver, Amanda L.; Solin, Jessica N.; Ma, Shaokang; Lesterhuis, W. Joost; Dick, Ian; Holt, Robert A.; Creaney, Jenette; Boon, Louis; Robinson, Bruce; Lake, Richard A.

    2016-01-01

    Abstract Introduction Regulatory T cells (Treg) play an important role in suppressing anti‐ immunity and their depletion has been linked to improved outcomes. To better understand the role of Treg in limiting the efficacy of anti‐cancer immunity, we used a Diphtheria toxin (DTX) transgenic mouse model to specifically target and deplete Treg. Methods Tumor bearing BALB/c FoxP3.dtr transgenic mice were subjected to different treatment protocols, with or without Treg depletion and tumor growth and survival monitored. Results DTX specifically depleted Treg in a transient, dose‐dependent manner. Treg depletion correlated with delayed tumor growth, increased effector T cell (Teff) activation, and enhanced survival in a range of solid tumors. Tumor regression was dependent on Teffs as depletion of both CD4 and CD8 T cells completely abrogated any survival benefit. Severe morbidity following Treg depletion was only observed, when consecutive doses of DTX were given during peak CD8 T cell activation, demonstrating that Treg can be depleted on multiple occasions, but only when CD8 T cell activation has returned to base line levels. Finally, we show that even minimal Treg depletion is sufficient to significantly improve the efficacy of tumor‐peptide vaccination. Conclusions BALB/c.FoxP3.dtr mice are an ideal model to investigate the full therapeutic potential of Treg depletion to boost anti‐tumor immunity. DTX‐mediated Treg depletion is transient, dose‐dependent, and leads to strong anti‐tumor immunity and complete tumor regression at high doses, while enhancing the efficacy of tumor‐specific vaccination at low doses. Together this data highlight the importance of Treg manipulation as a useful strategy for enhancing current and future cancer immunotherapies. PMID:28250921

  5. Homeostasis and function of regulatory T cells (Tregs) in vivo: lessons from TCR-transgenic Tregs

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    Attridge, Kesley; Walker, Lucy S K

    2014-01-01

    The identification of CD25 and subsequently Forkhead box protein 3 (Foxp3) as markers for regulatory T cells (Tregs) has revolutionized our ability to explore this population experimentally. In a similar vein, our understanding of antigen-specific Treg responses in vivo owes much to the fortuitous generation of T-cell receptor (TCR)-transgenic Tregs. This has permitted tracking of Tregs with a defined specificity in vivo, facilitating analysis of how encounter with cognate antigen shapes Treg homeostasis and function. Here, we review the key lessons learned from a decade of analysis of TCR-transgenic Tregs and set this in the broader context of general progress in the field. Use of TCR-transgenic Tregs has led to an appreciation that Tregs are a highly dynamic proliferative population in vivo, rather than an anergic population as they were initially portrayed. It is now clear that Treg homeostasis is positively regulated by encounter with self-antigen expressed on peripheral tissues, which is likely to be relevant to the phenomenon of peripheral repertoire reshaping that has been described for Tregs and the observation that the Treg TCR specificities vary by anatomical location. Substantial evidence has also accumulated to support the role of CD28 costimulation and interleukin-2 in Treg homeostasis. The availability of TCR-transgenic Tregs has enabled analysis of Treg populations that are sufficient or deficient in particular genes, without the comparison being confounded by repertoire alterations. This approach has yielded insights into genes required for Treg function in vivo, with particular progress being made on the role of ctla-4 in this context. As the prospect of manipulating Treg populations in the clinic becomes reality, a full appreciation of the rules governing their homeostasis will prove increasingly important. PMID:24712457

  6. The Four types of Tregs in malignant lymphomas

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    Wang Jing

    2011-12-01

    Full Text Available Abstract Regulatory T cells (Tregs are a specialized subpopulation of CD4+ T cells, which act to suppress the activation of other immune cells. Tregs represent important modulators for the interaction between lymphomas and host microenvironment. Lymphomas are a group of serious and frequently fatal malignant diseases of lymphocytes. Recent studies revealed that some lymphoma T cells might adopt a Treg profile. Assessment of Treg phenotypes and genotypes in patients may offer prediction of outcome in many types of lymphomas including diffuse large B-cell lymphoma, follicular lymphoma, cutaneous T cell lymphoma, and Hodgkin's lymphoma. Based on characterized roles of Tregs in lymphomas, we can categorize the various roles into four groups: (a suppressor Tregs; (b malignant Tregs; (c direct tumor-killing Tregs; and (d incompetent Tregs. The classification into four groups is significant in predicting prognosis and designing Tregs-based immunotherapies for treating lymphomas. In patients with lymphomas where Tregs serve either as suppressor Tregs or malignant Tregs, anti-tumor cytotoxicity is suppressed thus decreased numbers of Tregs are associated with a good prognosis. In contrast, in patients with lymphomas where Tregs serve as tumor-killing Tregs and incompetent Tregs, anti-tumor cytotoxicity is enhanced or anti-autoimmune Tregs activities are weakened thus increased numbers of Tregs are associated with a good prognosis and reduced numbers of Tregs are associated with a poor prognosis. However, the mechanisms underlying the various roles of Tregs in patients with lymphomas remain unknown. Therefore, further research is needed in this regard as well as the utility of Tregs as prognostic factors and therapy strategies in different lymphomas.

  7. Treg/IL-17 ratio and Treg differentiation in patients with COPD.

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    Yang Jin

    Full Text Available Chronic obstructive pulmonary disease (COPD is characterized by chronic pulmonary and systematic inflammation. An abnormal adaptive immune response leads to an imbalance between pro- and anti-inflammatory processes. T-helper (Th, T-cytotoxic (Tc and T-regulatory (Treg cells may play important roles in immune and inflammatory responses. This study was conducted to clarify the changes and imbalance of cytokines and T lymphocyte subsets in patients with COPD, especially during acute exacerbations (AECOPD.Twenty-three patients with stable COPD (SCOPD and 21 patients with AECOPD were enrolled in the present study. In addition, 20 age-, sex- and weight-matched non-smoking healthy volunteers were included as controls. The serum levels of selected cytokines (TGF-β, IL-10, TNF-α, IL-17 and IL-9 were measured by enzyme-linked immunosorbent assay (ELISA kits. Furthermore, the T lymphocyte subsets collected from peripheral blood samples were evaluated by flow cytometry after staining with anti-CD3-APC, anti-CD4-PerCP, anti-CD8- PerCP, anti-CD25-FITC and anti-FoxP3-PE monoclonal antibodies. Importantly, to remove the confounding effects of inflammatory factors, the authors introduced a concept of "inflammation adjustment" and corrected each measured value using representative inflammatory markers, such as TNF-α and IL-17.Unlike the other cytokines, serum TGF-β levels were considerably higher in patients with AECOPD relative to the control group regardless of adjustment. There were no significant differences in the percentages of either CD4+ or CD8+ T cells among the three groups. Although Tregs were relatively upregulated during acute exacerbations, their capacities of generation and differentiation were far from sufficient. Finally, the authors noted that the ratios of Treg/IL-17 were similar among groups.These observations suggest that in patients with COPD, especially during acute exacerbations, both pro-inflammatory and anti-inflammatory reactions

  8. Suppressive and immunoprotective functions of Tregs

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    Pushpa ePandiyan

    2011-11-01

    Full Text Available CD4+CD25+Foxp3+ T lymphocytes, known as regulatory T cells or Tregs, have been proposed to be a lineage of professional immune suppressive cells that exclusively counteract the effects of the immunoprotective "helper" and "cytotoxic" lineages of T lymphocytes. Here we discuss new concepts on the mechanisms and functions of Tregs. There are several key points we emphasize: 1. Tregs exert suppressive effects both directly on effector T cells and indirectly through antigen-presenting cells (APCs; 2. Regulation can occur through a novel mechanism of cytokine consumption to regulate as opposed to the usual mechanism of cytokine/chemokine production; 3. In cases where CD4+ effector T cells are directly inhibited by Tregs, it is chiefly through a mechanism of lymphokine withdrawal apoptosis leading to polyclonal deletion (PCD; and 4. Contrary to the current view, we discuss new evidence that Tregs, similar to other T cells lineages, can promote protective immune responses in certain infectious contexts (Pandiyan et al. 2011; Chen et al 2011. Although these points are at variance to varying degrees with the standard model of Treg behavior, we will recount developing findings that support these new concepts.

  9. Atherosclerosis-Driven Treg Plasticity Results in Formation of a Dysfunctional Subset of Plastic IFNγ+ Th1/Tregs.

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    Butcher, Matthew J; Filipowicz, Adam R; Waseem, Tayab C; McGary, Christopher M; Crow, Kevin J; Magilnick, Nathaniel; Boldin, Mark; Lundberg, Patric S; Galkina, Elena V

    2016-11-11

    Forkhead box P3 + T regulatory cells (Tregs) are key players in maintaining immune homeostasis. Evidence suggests that Tregs respond to environmental cues to permit or suppress inflammation. In atherosclerosis, Th1-driven inflammation affects Treg homeostasis, but the mechanisms governing this phenomenon are unclear. Here, we address whether atherosclerosis impacts Treg plasticity and functionality in Apoe - /- mice, and what effect Treg plasticity might have on the pathology of atherosclerosis. We demonstrate that atherosclerosis promotes Treg plasticity, resulting in the reduction of CXCR3 + Tregs and the accumulation of an intermediate Th1-like interferon (IFN)-γ + CCR5 + Treg subset (Th1/Tregs) within the aorta. Importantly, Th1/Tregs arise in atherosclerosis from bona fide Tregs, rather than from T-effector cells. We show that Th1/Tregs recovered from atherosclerotic mice are dysfunctional in suppression assays. Using an adoptive transfer system and plasticity-prone Mir146a -/- Tregs, we demonstrate that elevated IFNγ + Mir146a -/- Th1/Tregs are unable to adequately reduce atherosclerosis, arterial Th1, or macrophage content within Apoe -/- mice, in comparison to Mir146a +/+ Tregs. Finally, via single-cell RNA-sequencing and real-time -polymerase chain reaction, we show that Th1/Tregs possess a unique transcriptional phenotype characterized by coexpression of Treg and Th1 lineage genes and a downregulation of Treg-related genes, including Ikzf2, Ikzf4, Tigit, Lilrb4, and Il10. In addition, an ingenuity pathway analysis further implicates IFNγ, IFNα, interleukin-2, interleukin-7, CTLA-4 (cytotoxic T-lymphocyte-associated protein 4), T-cell receptor, and Csnk2b-related pathways in regulating Treg plasticity. Atherosclerosis drives Treg plasticity, resulting in the accumulation of dysfunctional IFNγ + Th1/Tregs that may permit further arterial inflammation and atherogenesis. © 2016 American Heart Association, Inc.

  10. Peritransplant Treg-Based Immunomodulation to Improve VCA Outcomes

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    2017-10-01

    orthotopic limb allografts in conjunction with TCR mAb and/or WT or HDAC-/- Treg cell administration 6-12 Milestone(s) Achieved: Efficacy of polyclonal WT...demethylation for each population (WT Tregs, HDAC6-/- Tregs, HDAC11-/- Tregs). 10-12 Subtask 2: Perform orthotopic limb allografts in conjunction ...function, and assessment of TSDR demethylation. • Subtask 3: Perform orthotopic limb allografts in conjunction with TCR mAb and/or WT or HDAC-/- Treg cell

  11. Natural killer cells regulate Th1/Treg and Th17/Treg balance in chlamydial lung infection.

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    Li, Jing; Dong, Xiaojing; Zhao, Lei; Wang, Xiao; Wang, Yan; Yang, Xi; Wang, Hong; Zhao, Weiming

    2016-07-01

    Natural killer (NK) cell is an important component in innate immunity, playing a critical role in bridging innate and adaptive immunity by modulating the function of other immune cells including T cells. In this study, we focused on the role of NK cells in regulating Th1/Treg and Th17/Treg balance during chlamydial lung infection. We found that NK cell-depleted mice showed decreased Th1 and Th17 cells, which was correlated with reduced interferon-γ, interleukin (IL)-12, IL-17 and IL-22 production as well as T-bet and receptor-related orphan receptor gamma t expression compared with mice treated with the isotype control antibody. In contrast, NK cell depletion significantly increased Treg in cell number and related transcription factor (Foxp3) expression. The opposite trends of changes of Th1/Th17 and Treg led to significant reduction in the Th1/Treg and Th17/Treg ratios. The data implicate that NK cells play an important role in host defence against chlamydial lung infection, mainly through maintaining Th1/Treg and Th17/Treg balance. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  12. Polyclonal Recipient nTregs Are Superior to Donor or Third-Party Tregs in the Induction of Transplantation Tolerance

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    Nina Pilat

    2015-01-01

    Full Text Available Induction of donor-specific tolerance is still considered as the “Holy Grail” in transplantation medicine. The mixed chimerism approach is virtually the only tolerance approach that was successfully translated into the clinical setting. We have previously reported successful induction of chimerism and tolerance using cell therapy with recipient T regulatory cells (Tregs to avoid cytotoxic recipient treatment. Treg therapy is limited by the availability of cells as large-scale expansion is time-consuming and associated with the risk of contamination with effector cells. Using a costimulation-blockade based bone marrow (BM transplantation (BMT model with Treg therapy instead of cytoreductive recipient treatment we aimed to determine the most potent Treg population for clinical translation. Here we show that CD4+CD25+ in vitro activated nTregs are superior to TGFβ induced iTregs in promoting the induction of chimerism and tolerance. Therapy with nTregs (but not iTregs led to multilineage chimerism and donor-specific tolerance in mice receiving as few as 0.5 × 106 cells. Moreover, we show that only recipient Tregs, but not donor or third-party Tregs, had a beneficial effect on BM engraftment at the tested doses. Thus, recipient-type nTregs significantly improve chimerism and tolerance and might be the most potent Treg population for translation into the clinical setting.

  13. IL-34 is a Treg-specific cytokine and mediates transplant tolerance

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    Bézie, Séverine; Picarda, Elodie; Ossart, Jason; Tesson, Laurent; Usal, Claire; Renaudin, Karine; Anegon, Ignacio; Guillonneau, Carole

    2015-01-01

    Cytokines and metabolic pathway–controlling enzymes regulate immune responses and have potential as powerful tools to mediate immune tolerance. Blockade of the interaction between CD40 and CD40L induces long-term cardiac allograft survival in rats through a CD8+CD45RClo Treg potentiation. Here, we have shown that the cytokine IL-34, the immunoregulatory properties of which have not been previously studied in transplantation or T cell biology, is expressed by rodent CD8+CD45RClo Tregs and huma...

  14. Foxp3+ Treg expanded from patients with established diabetes reduce Helios expression while retaining normal function compared to healthy individuals.

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    Weiting Du

    Full Text Available Foxp3(+ regulatory T cells (Treg play a crucial role in regulating immune tolerance. The use of Treg to restore immune tolerance is considered an attractive novel approach to inhibit autoimmune disease, including type 1 diabetes (T1D, and to prevent rejection of organ transplants. In view of the goal of developing autologous Treg-based cell therapy for patients with long-term (>15 years T1D, it will be necessary to expand a sufficient amount of functional Treg in vitro in order to study and compare Treg from T1D patients and healthy subjects. Our results have demonstrated that there is a comparable frequency of Treg in the peripheral blood lymphocytes (PBLs of patients with long-term T1D relative to those in healthy subjects; however, Th1 cells, but not Th17 cells, were increased in the T1D patients. Further, more Treg in PBLs from T1D patients than from healthy subjects expressed the CD45RO(+ memory cell phenotype, suggesting they were antigen-experienced cells. After isolation, Treg from both T1D patients and healthy subjects were successfully expanded with high purity. Although there was no difference in Helios expression on Treg in PBLs, in vitro expansion led to fewer Helios-expressing Treg from T1D patients than healthy subjects. While more Th1-like Treg expressing IFN-γ or TNF-α were found in the PBLs of T1D patients than healthy controls, there was no such difference in the expanded Treg. Importantly, expanded Treg from both subject groups were able to suppress autologous or allogeneic CD8(+ effector T cells equally well. Our findings demonstrate that a large number of ex vivo expanded functional Treg can be obtained from long-term T1D patients, although fewer expanded Treg expressed a high level of Helios. Thus, based on the positive outcomes, these potent expanded Treg from diabetic human patients may be useful in treating T1D or preventing islet graft rejection.

  15. Deletion of Fanca or Fancd2 dysregulates Treg in mice

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    Du, Wei; Erden, Ozlem; Wilson, Andrew; Sipple, Jared M.; Schick, Jonathan; Mehta, Parinda; Myers, Kasiani C.; Steinbrecher, Kris A.; Davies, Stella M.

    2014-01-01

    Fanconi anemia (FA) is a genetic disorder associated with bone marrow (BM) failure and leukemia. Recent studies demonstrate variable immune defects in FA. However, the cause for FA immunodeficiency is unknown. Here we report that deletion of Fanca or Fancd2 dysregulates the suppressive activity of regulatory T cells (Tregs), shown functionally as exacerbation of graft-vs-host disease (GVHD) in mice. Recipient mice of Fanca−/− or Fancd2−/− BM chimeras exhibited severe acute GVHD after allogeneic BM transplantation (BMT). T cells from Fanca−/− or Fancd2−/− mice induced higher GVHD lethality than those from wild-type (WT) littermates. FA Tregs possessed lower proliferative suppression potential compared with WT Tregs, as demonstrated by in vitro proliferation assay and BMT. Analysis of CD25+Foxp3+ Tregs indicated that loss of Fanca or Fancd2 dysregulated Foxp3 target gene expression. Additionally, CD25+Foxp3+ Tregs of Fanca−/− or Fancd2−/− mice were less efficient in suppressing the production of GVHD-associated inflammatory cytokines. Consistently, aberrant NF-κB activity was observed in infiltrated T cells from FA GVHD mice. Conditional deletion of p65 in FA Tregs decreased GVHD mortality. Our study uncovers an essential role for FA proteins in maintaining Treg homeostasis, possibly explaining, at least in part, the immune deficiency reported in some FA patients. PMID:24501220

  16. Deletion of Fanca or Fancd2 dysregulates Treg in mice.

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    Du, Wei; Erden, Ozlem; Wilson, Andrew; Sipple, Jared M; Schick, Jonathan; Mehta, Parinda; Myers, Kasiani C; Steinbrecher, Kris A; Davies, Stella M; Pang, Qishen

    2014-03-20

    Fanconi anemia (FA) is a genetic disorder associated with bone marrow (BM) failure and leukemia. Recent studies demonstrate variable immune defects in FA. However, the cause for FA immunodeficiency is unknown. Here we report that deletion of Fanca or Fancd2 dysregulates the suppressive activity of regulatory T cells (Tregs), shown functionally as exacerbation of graft-vs-host disease (GVHD) in mice. Recipient mice of Fanca(-/-) or Fancd2(-/-) BM chimeras exhibited severe acute GVHD after allogeneic BM transplantation (BMT). T cells from Fanca(-/-) or Fancd2(-/-) mice induced higher GVHD lethality than those from wild-type (WT) littermates. FA Tregs possessed lower proliferative suppression potential compared with WT Tregs, as demonstrated by in vitro proliferation assay and BMT. Analysis of CD25(+)Foxp3(+) Tregs indicated that loss of Fanca or Fancd2 dysregulated Foxp3 target gene expression. Additionally, CD25(+)Foxp3(+) Tregs of Fanca(-/-) or Fancd2(-/-) mice were less efficient in suppressing the production of GVHD-associated inflammatory cytokines. Consistently, aberrant NF-κB activity was observed in infiltrated T cells from FA GVHD mice. Conditional deletion of p65 in FA Tregs decreased GVHD mortality. Our study uncovers an essential role for FA proteins in maintaining Treg homeostasis, possibly explaining, at least in part, the immune deficiency reported in some FA patients.

  17. CCR9 Is Not Required for the Homing of Pro-inflammatory Effector T cells, but Is Crucial for Recruitment and Expansion of FoxP3+ CD8+ Tregs in the Small Intestine

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    Gomez-Casado, Cristina; Joeris, Thorsten; Holmkvist, Petra

    Chemokine receptor 9 (CCR9) is required for the homeostatic recruitment of T cells to the mucosa of the small intestine. Accordingly, CCR9 has been suggested as a potential target to inhibit the recruitment of proinflammatory effector T cells (Teff) in inflammatory bowel disease (IBD). Since...... the contribution of CCR9 to the recruitment of Teff in inflammation is not entirely clear, we aimed to address this question using IFABPtOva mice. These mice express Ovalbumin (Ova) specifically in small intestinal epithelial cells, which allows triggering of acute inflammation following transfer of Ova......-specific CD8+ T cells (OT-I cells) and adjuvant treatment. Strikingly, intestinal inflammation in IFABP-tOva mice could also be triggered following transfer of CCR9-deficient OT-I cells, demonstrating that CCR9 is not required for homing of Teff cells. Interestingly, OTI cells transferred to IFABP-tOva mice...

  18. The Treg/Th17 Paradigm in Lung Cancer

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    Min-Chao Duan

    2014-01-01

    Full Text Available Pathogenic mechanisms underlying the development of lung cancer are very complex and not yet entirely clarified. T lymphocytes and their immune-regulatory cytokines play a pivotal role in controlling tumor growth and metastasis. Following activation by unique cytokines, CD4+ T helper cells differentiate into Th1, Th2, Th17, and regulatory T cells (Tregs. Traditionally, research in lung cancer immunity has focused almost exclusively on Th1/Th2 cell balance. Recently, Th17 cells and Tregs represent an intriguing issue to be addressed in lung cancer pathogenesis. Tregs play an important role in the preservation of self-tolerance and modulation of overall immune responses against tumor cells. Th17 cells directly or via other proinflammatory cytokines modulate antitumor immune responses. Notably, there is a close relation between Tregs and Th17 cells. However, the possible interaction between these subsets in lung cancer remains to be elucidated. In this setting, targeting Treg/Th17 balance for therapeutic purposes may represent a useful tool for lung cancer treatment in the future. The purpose of this review is to discuss recent findings of the role of these novel populations in lung cancer immunity and to highlight the pleiotropic effects of these subsets on the development and regulation of lung cancer.

  19. Increased Th17/Treg Ratio in Poststroke Fatigue

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    Xinjing Liu

    2015-01-01

    Full Text Available Fatigue is a major debilitating symptom after stroke. The biological mechanisms underlying poststroke fatigue (PFS are unknown. We hypothesized that PSF is associated with an alteration in the balance between Th17 and Treg cells. To test this hypothesis we assessed fatigue in 30 stroke survivors using the Fatigue Scale for Motor and Cognitive Functions (FSMC. Peripheral blood was collected for assessment of Th17 and Treg cell populations and measurement of interleukin-10 (IL-10. Participants were dichotomized into severe fatigue n=14 and low-moderate fatigue n=16 groups by K-mean cluster analysis of FSMC scores. There were no group differences in age, gender, stroke type, stroke severity, or time since stroke. Stroke survivors in the severe fatigue group reported greater anxiety p=0.004 and depression p=0.001 than in the low-moderate fatigue group. The ratio of Th17 to Treg cells was significantly increased in the severe fatigue group relative to the mild-moderate fatigue group p=0.035. Serum levels of IL-10 negatively correlated withTh17/Treg ratio (r=-0.408,  p=0.025. Our preliminary findings suggest that an imbalance in the Th17/Treg ratio is associated with the severity of PSF.

  20. Differential responses of human regulatory T cells (Treg and effector T cells to rapamycin.

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    Laura Strauss

    Full Text Available BACKGROUND: The immunosuppressive drug rapamycin (RAPA promotes the expansion of CD4(+ CD25(highFoxp3(+ regulatory T cells via mechanisms that remain unknown. Here, we studied expansion, IL-2R-gamma chain signaling, survival pathways and resistance to apoptosis in human Treg responding to RAPA. METHODOLOGY/PRINCIPAL FINDINGS: CD4(+CD25(+ and CD4(+CD25(neg T cells were isolated from PBMC of normal controls (n = 21 using AutoMACS. These T cell subsets were cultured in the presence of anti-CD3/CD28 antibodies and 1000 IU/mL IL-2 for 3 to 6 weeks. RAPA (1-100 nM was added to half of the cultures. After harvest, the cell phenotype, signaling via the PI3K/mTOR and STAT pathways, expression of survival proteins and Annexin V binding were determined and compared to values obtained with freshly-separated CD4(+CD25(high and CD4(+CD25(neg T cells. Suppressor function was tested in co-cultures with autologous CFSE-labeled CD4(+CD25(neg or CD8(+CD25(neg T-cell responders. The frequency and suppressor activity of Treg were increased after culture of CD4(+CD25(+ T cells in the presence of 1-100 nM RAPA (p<0.001. RAPA-expanded Treg were largely CD4(+CD25(highFoxp3(+ cells and were resistant to apoptosis, while CD4(+CD25(neg T cells were sensitive. Only Treg upregulated anti-apoptotic and down-regulated pro-apoptotic proteins. Treg expressed higher levels of the PTEN protein than CD4(+CD25(neg cells. Activated Treg+/-RAPA preferentially phosphorylated STAT5 and STAT3 and did not utilize the PI3K/mTOR pathway. CONCLUSIONS/SIGNIFICANCE: RAPA favors Treg expansion and survival by differentially regulating signaling, proliferation and sensitivity to apoptosis of human effector T cells and Treg after TCR/IL-2 activation.

  1. The success of assisted reproduction technologies in relation to composition of the total regulatory T cell (Treg) pool and different Treg subsets.

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    Schlossberger, V; Schober, L; Rehnitz, J; Schaier, M; Zeier, M; Meuer, S; Schmitt, E; Toth, B; Strowitzki, T; Steinborn, A

    2013-11-01

    Are there differences in composition of the total regulatory T cell (Treg) pool and distinct Treg subsets (naïve CD45RA(+)-Tregs, HLA-DR(-)- and HLA-DR(+)-memory Tregs) between successfully and non-successfully IVF/ICSI-treated women? Non-successfully IVF/ICSI-treated women have a decreased percentage of naïve CD45RA(+)-Tregs and an increased percentage of HLA-DR(-)-memory Tregs within the total Treg pool. Immunosuppressive Tregs play a significant role in human reproduction and studies have shown that their number and function are reduced in reproductive failure and complications of pregnancy such as pre-eclampsia and preterm labor. However, no data exist concerning the importance of Tregs for a successful outcome following assisted reproduction technologies. Blood samples were obtained from 210 women undergoing IVF/ICSI treatment, where 14 patients were excluded due to biochemical pregnancy or missed abortion. Age control blood samples were collected from 20 neonates and 176 healthy female volunteers. The study was performed between October 2010 and March 2012. In this study, we determined prospectively the quantity and composition of the total CD4(+)CD127(low+/-)CD25(+)FoxP3(+)-Treg pool and three different Treg subsets (naïve CD45RA(+)-Tregs, HLA-DR(-)- and HLA-DR(+)-memory Tregs) in all women undergoing IVF/ICSI treatment. We examined whether there were differences between those who became pregnant (n = 36) and those who did not (n = 160). The blood samples were collected within 1 h before the embryo transfer and analyzed by six-color flow cytometry. In order to evaluate these results with regard to the normal age-related changes in composition of the total Treg pool, the same analysis was performed using samples of umbilical cord blood and from healthy female volunteers aged between 17 and 76 years. The composition of the total Treg pool was documented for successfully IVF/ICSI-treated women (n = 5) throughout their pregnancy and we assessed the

  2. Phenotypic analysis of prostate-infiltrating lymphocytes reveals TH17 and Treg skewing.

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    Sfanos, Karen Sandell; Bruno, Tullia C; Maris, Charles H; Xu, Lauren; Thoburn, Christopher J; DeMarzo, Angelo M; Meeker, Alan K; Isaacs, William B; Drake, Charles G

    2008-06-01

    Pathologic examination of prostate glands removed from patients with prostate cancer commonly reveals infiltrating CD4+ and CD8+ T cells. Little is known about the phenotype of these cells, despite accumulating evidence suggesting a potential role for chronic inflammation in the etiology of prostate cancer. We developed a technique that samples the majority of the peripheral prostate through serial needle aspirates. CD4+ prostate-infiltrating lymphocytes (PIL) were isolated using magnetic beads and analyzed for subset skewing using both flow cytometry and quantitative reverse transcription-PCR. The transcriptional profile of fluorescence-activated cell sorted prostate-infiltrating regulatory T cells (CD4+, CD25+, GITR+) was compared with naïve, peripheral blood T cells using microarray analysis. CD4+ PIL showed a paucity of TH2 (interleukin-4-secreting) cells, a surprising finding given the generally accepted association of these cells with chronic, smoldering inflammation. Instead, CD4+ PIL seemed to be skewed towards a regulatory Treg phenotype (FoxP3+) as well as towards the TH17 phenotype (interleukin-17+). We also found that a preponderance of TH17-mediated inflammation was associated with a lower pathologic Gleason score. These protein level data were reflected at the message level, as analyzed by quantitative reverse transcription-PCR. Microarray analysis of pooled prostate-infiltrating T(reg) revealed expected Treg-associated transcripts (FoxP3, CTLA-4, GITR, LAG-3) as well as a number of unique cell surface markers that may serve as additional Treg markers. Taken together, these data suggest that TH17 and/or Treg CD4+ T cells (rather than TH2 T cells) may be involved in the development or progression of prostate cancer.

  3. Treg subsets in inflammatory bowel disease and colorectal carcinoma: Characteristics, role, and therapeutic targets

    NARCIS (Netherlands)

    van Herk, Egbert H.; te Velde, Anje A.

    2016-01-01

    T regulatory cells (Tregs) play an important role in the regulation of autoimmunity, autoinflammation, allergic diseases, infection, and the tumor environment. Different subsets are characterized that use a number of regulatory mechanisms. Tregs can influence the progression of inflammatory bowel

  4. CD4+CD25+ regulatory T cells control CD8+ T-cell effector differentiation by modulating IL-2 homeostasis

    Science.gov (United States)

    McNally, Alice; Hill, Geoffrey R.; Sparwasser, Tim; Thomas, Ranjeny; Steptoe, Raymond J.

    2011-01-01

    CD4+CD25+ regulatory T cells (Treg) play a crucial role in the regulation of immune responses. Although many mechanisms of Treg suppression in vitro have been described, the mechanisms by which Treg modulate CD8+ T cell differentiation and effector function in vivo are more poorly defined. It has been proposed, in many instances, that modulation of cytokine homeostasis could be an important mechanism by which Treg regulate adaptive immunity; however, direct experimental evidence is sparse. Here we demonstrate that CD4+CD25+ Treg, by critically regulating IL-2 homeostasis, modulate CD8+ T-cell effector differentiation. Expansion and effector differentiation of CD8+ T cells is promoted by autocrine IL-2 but, by competing for IL-2, Treg limit CD8+ effector differentiation. Furthermore, a regulatory loop exists between Treg and CD8+ effector T cells, where IL-2 produced during CD8+ T-cell effector differentiation promotes Treg expansion. PMID:21502514

  5. Challenges in cryopreservation of regulatory T cells (Tregs) for clinical therapeutic applications.

    Science.gov (United States)

    Golab, Karolina; Leveson-Gower, Dennis; Wang, Xiao-Jun; Grzanka, Jakub; Marek-Trzonkowska, Natalia; Krzystyniak, Adam; Millis, J Michael; Trzonkowski, Piotr; Witkowski, Piotr

    2013-07-01

    Promising results of initial studies applying ex-vivo expanded regulatory T cell (Treg) as a clinical intervention have increased interest in this type of the cellular therapy and several new clinical trials involving Tregs are currently on the way. Methods of isolation and expansion of Tregs have been studied and optimized to the extent that such therapy is feasible, and allows obtaining sufficient numbers of Tregs in the laboratory following Good Manufacturing Practice (GMP) guidelines. Nevertheless, Treg therapy could even more rapidly evolve if Tregs could be efficiently cryopreserved and stored for future infusion or expansions rather than utilization of only freshly isolated and expanded cells as it is preferred now. Currently, our knowledge regarding the impact of cryopreservation on Treg recovery, viability, and functionality is still limited. Based on experience with cryopreserved peripheral blood mononuclear cells (PBMCs), cryopreservation may have a detrimental effect on Tregs, can decrease Treg viability, cause abnormal cytokine secretion, and compromise expression of surface markers essential for proper Treg function and processing. Therefore, optimal strategies and conditions for Treg cryopreservation in conjunction with cell culture, expansion, and processing for clinical application still need to be investigated and defined. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Regulatory T cells (Treg and Their Roles in Immune System with Respect to Immunopathological Disorders

    Directory of Open Access Journals (Sweden)

    Kateřina Kondělková

    2010-01-01

    Full Text Available Regulatory T cells (Tregs are a specialized subpopulation of T cells that act to suppress immune response, thereby maintaining homeostasis and self-tolerance. It has been shown that Tregs are able to inhibit T cell proliferation and cytokine production and play a critical role in preventing autoimmunity. Different subsets with various functions of Treg cells exist. Tregs can be usually identified by flow cytometry. The most specific marker for these cells is FoxP3, which is localized intracellulary. Selected surface markers such as CD25high (high molecular density and CD127low (low molecular density could serve as surrogate markers to detect Tregs in a routine clinical practice. Dysregulation in Treg cell frequency or functions may lead to the development of autoimmune disease. Therapeutical Treg modulation is considered to be a promising therapeutical approach to treat some selected disorders, such as allergies, and to prevent allograft rejection.

  7. Changes in natural Foxp3(+Treg but not mucosally-imprinted CD62L(negCD38(+Foxp3(+Treg in the circulation of celiac disease patients.

    Directory of Open Access Journals (Sweden)

    Marieke A van Leeuwen

    Full Text Available BACKGROUND: Celiac disease (CD is an intestinal inflammation driven by gluten-reactive CD4(+ T cells. Due to lack of selective markers it has not been determined whether defects in inducible regulatory T cell (Treg differentiation are associated with CD. This is of importance as changes in numbers of induced Treg could be indicative of defects in mucosal tolerance development in CD. Recently, we have shown that, after encounter of retinoic acid during differentiation, circulating gut-imprinted T cells express CD62L(negCD38(+. Using this new phenotype, we now determined whether alterations occur in the frequency of natural CD62L(+Foxp3(+ Treg or mucosally-imprinted CD62L(negCD38(+Foxp3(+ Treg in peripheral blood of CD patients. In particular, we compared pediatric CD, aiming to select for disease at onset, with adult CD. METHODS: Cell surface markers, intracellular Foxp3 and Helios were determined by flow cytometry. Foxp3 expression was also detected by immunohistochemistry in duodenal tissue of CD patients. RESULTS: In children, the percentages of peripheral blood CD4(+Foxp3(+ Treg were comparable between CD patients and healthy age-matched controls. Differentiation between natural and mucosally-imprinted Treg on the basis of CD62L and CD38 did not uncover differences in Foxp3. In adult patients on gluten-free diet and in refractory CD increased percentages of circulating natural CD62L(+Foxp3(+ Treg, but normal mucosally-imprinted CD62L(negCD38(+Foxp3(+ Treg frequencies were observed. CONCLUSIONS: Our data exclude that significant numeric deficiency of mucosally-imprinted or natural Foxp3(+ Treg explains exuberant effector responses in CD. Changes in natural Foxp3(+ Treg occur in a subset of adult patients on a gluten-free diet and in refractory CD patients.

  8. Aberrant Muscle Antigen Exposure in Mice Is Sufficient to Cause Myositis in a Treg Cell–Deficient Milieu

    Science.gov (United States)

    Young, Nicholas A; Sharma, Rahul; Friedman, Alexandra K; Kaffenberger, Benjamin H; Bolon, Brad; Jarjour, Wael N

    2013-01-01

    Objective Myositis is associated with muscle-targeted inflammation and is observed in some Treg cell–deficient mouse models. Because an autoimmune pathogenesis has been strongly implicated, the aim of this study was to investigate the hypothesis that abnormal exposure to muscle antigens, as observed in muscle injury, can induce autoimmune-mediated myositis in susceptible hosts. Methods FoxP3 mutant (scurfy) mice were mated to synaptotagmin VII (Syt VII) mutant mice, which resulted in a new mouse strain that combines impaired membrane resealing with Treg cell deficiency. Lymphocyte preparations from double-mutant mice were adoptively transferred intraperitoneally, with or without purified Treg cells, into recombination-activating gene 1 (RAG-1)–null recipients. Lymph node cells from mice with the FoxP3 mutation were transferred into RAG-1–null mice either 1) intraperitoneally in conjunction with muscle homogenate or purified myosin protein or 2) intramuscularly with or without cotransfer of purified Treg cells. Results FoxP3-deficient mouse lymph node cells transferred in conjunction with myosin protein or muscle homogenate induced robust skeletal muscle inflammation. The infiltrates consisted predominantly of CD4+ and CD8+ T cells, a limited number of macrophages, and no B cells. Significant inflammation was also seen in similar experiments using lymph node cells from FoxP3/Syt VII double-mutant mice but was absent in experiments using adoptive transfer of FoxP3 mutant mouse cells alone. The cotransfer of Treg cells completely suppressed myositis. Conclusion These data, derived from a new, reproducible model, demonstrate the critical roles of Treg cell deficiency and aberrant muscle antigen exposure in the priming of autoreactive cells to induce myositis. This mouse system has multifaceted potential for examining the interplay in vivo between tissue injury and autoimmunity. PMID:24022275

  9. Acyclovir inhibition of IDO to decrease Tregs as a glioblastoma treatment adjunct

    Directory of Open Access Journals (Sweden)

    Söderlund Johan

    2010-08-01

    Full Text Available Abstract Regulatory T cells, Tregs, are a subset of lymphocytes that have immunosuppressive attributes. They are elevated in blood of glioblastoma patients and within this tumor's tissue itself. Indoleamine 2,3-dioxygenase, IDO, converts tryptophan to kynurenine. IDO activity enhances Treg formation by pathways that are unknown. Experimentally, inhibition of IDO decreases Treg function and number in rodents. The common anti-viral agent acyclovir inhibits IDO. Acyclovir may thereby decrease Treg function in glioblastoma. If it can be confirmed that Treg counts are elevated in glioblastoma patients' tumor tissue, and if we can document acyclovir's lowering of tissue Treg counts by a small trial of acyclovir in pre-operative glioblastoma patients, a trial of acyclovir effect on survival should be done given the current poor prognosis of glioblastoma and the well-established safety and low side effect burden of acyclovir.

  10. Acid Sphingomyelinase (ASM) is a Negative Regulator of Regulatory T Cell (Treg) Development.

    Science.gov (United States)

    Zhou, Yuetao; Salker, Madhuri S; Walker, Britta; Münzer, Patrick; Borst, Oliver; Gawaz, Meinrad; Gulbins, Erich; Singh, Yogesh; Lang, Florian

    2016-01-01

    Regulatory T cell (Treg) is required for the maintenance of tolerance to various tissue antigens and to protect the host from autoimmune disorders. However, Treg may, indirectly, support cancer progression and bacterial infections. Therefore, a balance of Treg function is pivotal for adequate immune responses. Acid sphingomyelinase (ASM) is a rate limiting enzyme involved in the production of ceramide by breaking down sphingomyelin. Previous studies in T-cells have suggested that ASM is involved in CD28 signalling, T lymphocyte granule secretion, degranulation, and vesicle shedding similar to the formation of phosphatidylserine-exposing microparticles from glial cells. However, whether ASM affects the development of Treg has not yet been described. Splenocytes, isolated Naive T lymphocytes and cultured T cells were characterized for various immune T cell markers by flow cytometery. Cell proliferation was measured by Carboxyfluorescein succinimidyl ester (CFSE) dye, cell cycle analysis by Propidium Iodide (PI), mRNA transcripts by q-RT PCR and protein expression by Western Blotting respectively. ASM deficient mice have higher number of Treg compared with littermate control mice. In vitro induction of ASM deficient T cells in the presence of TGF-β and IL-2 lead to a significantly higher number of Foxp3+ induced Treg (iTreg) compared with control T-cells. Further, ASM deficient iTreg has less AKT (serine 473) phosphorylation and Rictor levels compared with control iTreg. Ceramide C6 led to significant reduction of iTreg in both ASM deficient and WT mice. The reduction in iTreg leads to induction of IL-1β, IL-6 and IL-17 but not IFN-γ mRNA levels. ASM is a negative regulator of natural and iTreg. © 2016 The Author(s) Published by S. Karger AG, Basel.

  11. Development of assay platforms for in vitro screening of Treg modulating potential of pharmacological compounds

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Holmstrøm, Kim; Jørgensen, Flemming

    2015-01-01

    that investigates Treg modulation by current drugs. For such research as well as for novel cell based therapies based on Treg infusions, rapid in vitro assays as well as functional assays based on inhibitory capacity of Tregs are required. Here, we report on such assays using highly pure fluorescence-activated cell...... and TNF-α. In conclusion, these assays have the potential for use in pharmacological screening and discovery in relation to drug development in immunology....

  12. Dendritic cells decreased the concomitant expanded Tregs and Tregs related IL-35 in cytokine-induced killer cells and increased their cytotoxicity against leukemia cells.

    Directory of Open Access Journals (Sweden)

    Ying Pan

    Full Text Available Regulatory T cells (Tregs are potent immunosuppressive cells and essential for inducing immune tolerance. Recent studies have reported that Tregs and Tregs related cytokines can inhibit the antitumor activity of cytokine-induced killer (CIK cells, but dendritic cells co-cultured CIK (DC-CIK cells can be used for induction of a specific immune response by blocking of Tregs and TGF-β, IL-10. As a novel identified cytokine, IL-35 is specially produced by Tregs and plays an essential role in immune regulation. However, it remains unknown whether IL-35 roles in tumor immunotherapy mediated by CIK and DC-CIK cells. In this study, we cultured CIK and DC-CIK cells from the same healthy adult samples, and investigated their phenotype, proliferation, cytotoxic activity against leukemia cell lines K562 and NB4 by FCM and CCK-8, measured IL-35, TGF-β and IL-10 protein by ELISA, detected Foxp3, IL-35 and IL-35 receptor mRNA by Real-time PCR, respectively. We found Tregs and IL-35 concomitantly expanded by a time-dependent way during the generation of CIK cells, but DC significantly down-regulated the expression of them and simultaneously up-regulated the proliferation ability as well as cytotoxic activity of CIK cells against leukemia cell lines. Therefore, our data suggested that DC decreased concomitant expanded Tregs and Tregs related IL-35 in CIK cells and might contribute to improve their cytotoxicity against leukemia cells in vitro.

  13. The Dynamics of Treg/Th17 and the Imbalance of Treg/Th17 in Clonorchis sinensis-Infected Mice

    Science.gov (United States)

    Hua, Hui; Li, Bo; Zhang, Bo; Yu, Qian; Li, Xiang-Yang; Liu, Ying; Pan, Wei; Liu, Xiang-Ye; Tang, Ren-Xian; Zheng, Kui-Yang

    2015-01-01

    Clonorchiasis, caused by the liver fluke Clonorchis sinensis, is a chronic parasitic infection regulated by T cell subsets. An imbalance of CD4+CD25+ Foxp3+regulatory T (Treg) and interleukin (IL)-17-secreting T cells (Th17) may control inflammation and play an important role in the pathogenesis of immune evasion. In the present study, we assessed the dynamics of Treg/Th17 and determined whether the Treg/Th17 ratio is altered in C. sinensis-infected mice. The results showed that the percentages of splenic Treg cells in CD4+ T cells were suppressed on day 14 post-infection (PI) but increased on day 56 PI, while Th17 cells were increased on day 56 PI compared with normal control (NC) mice. The Treg/Th17 ratio steadily increased from day 28 to day 56 PI. The hepatic levels of their specific transcription factors (Foxp3 for Treg and RORγt for Th17) were increased in C. sinensis-infected mice from day 14 to 56 PI, and significantly higher than those in NC mice. Meanwhile, serum levels of IL-2 and IL-17 were profoundly increased in C. sinensis-infected mice throughout the experiment; while the concentrations of IL-6 and transforming growth factor β1 (TGF-β1) peaked on day 14 PI, but then decreased on day 28 and 56 PI. Our results provide the first evidence of an increased Treg/Th17 ratio in C. sinensis-infected mice, suggesting that a Treg/Th17 imbalance may play a role in disease outcomes of clonorchiasis. PMID:26599407

  14. The Dynamics of Treg/Th17 and the Imbalance of Treg/Th17 in Clonorchis sinensis-Infected Mice.

    Directory of Open Access Journals (Sweden)

    Chao Yan

    Full Text Available Clonorchiasis, caused by the liver fluke Clonorchis sinensis, is a chronic parasitic infection regulated by T cell subsets. An imbalance of CD4+CD25+ Foxp3+regulatory T (Treg and interleukin (IL-17-secreting T cells (Th17 may control inflammation and play an important role in the pathogenesis of immune evasion. In the present study, we assessed the dynamics of Treg/Th17 and determined whether the Treg/Th17 ratio is altered in C. sinensis-infected mice. The results showed that the percentages of splenic Treg cells in CD4+ T cells were suppressed on day 14 post-infection (PI but increased on day 56 PI, while Th17 cells were increased on day 56 PI compared with normal control (NC mice. The Treg/Th17 ratio steadily increased from day 28 to day 56 PI. The hepatic levels of their specific transcription factors (Foxp3 for Treg and RORγt for Th17 were increased in C. sinensis-infected mice from day 14 to 56 PI, and significantly higher than those in NC mice. Meanwhile, serum levels of IL-2 and IL-17 were profoundly increased in C. sinensis-infected mice throughout the experiment; while the concentrations of IL-6 and transforming growth factor β1 (TGF-β1 peaked on day 14 PI, but then decreased on day 28 and 56 PI. Our results provide the first evidence of an increased Treg/Th17 ratio in C. sinensis-infected mice, suggesting that a Treg/Th17 imbalance may play a role in disease outcomes of clonorchiasis.

  15. Clinical Grade Regulatory CD4+ T Cells (Tregs: Moving Toward Cellular-Based Immunomodulatory Therapies

    Directory of Open Access Journals (Sweden)

    Richard Duggleby

    2018-02-01

    Full Text Available Regulatory T cells (Tregs are CD4+ T cells that are key players of immune tolerance. They are powerful suppressor cells, able to impact the function of numerous immune cells, including key effectors of inflammation such as effector T cells. For this reason, Tregs are an ideal candidate for the development of cell therapy approaches to modulate immune responses. Treg therapy has shown promising results so far, providing key knowledge on the conditions in which these cells can provide protection and demonstrating that they could be an alternative to current pharmacological immunosuppressive therapies. However, a more comprehensive understanding of their characteristics, isolation, activation, and expansion is needed to be able design cost effective therapies. Here, we review the practicalities of making Tregs a viable cell therapy, in particular, discussing the challenges faced in isolating and manufacturing Tregs and defining what are the most appropriate applications for this new therapy.

  16. Time-resolved transcriptome and proteome landscape of human regulatory T cell (Treg) differentiation reveals novel regulators of FOXP3

    KAUST Repository

    Schmidt, Angelika; Marabita, Francesco; Kiani, Narsis A.; Gross, Catharina C.; Johansson, Henrik J.; É liá s, Szabolcs; Rautio, Sini; Eriksson, Matilda; Fernandes, Sunjay Jude; Silberberg, Gilad; Ullah, Ubaid; Bhatia, Urvashi; Lä hdesmä ki, Harri; Lehtiö , Janne; Gomez-Cabrero, David; Wiendl, Heinz; Lahesmaa, Riitta; Tegner, Jesper

    2018-01-01

    BackgroundRegulatory T cells (Tregs) expressing the transcription factor FOXP3 are crucial mediators of self-tolerance, preventing autoimmune diseases but possibly hampering tumor rejection. Clinical manipulation of Tregs is of great interest

  17. Expansion of Human Tregs from Cryopreserved Umbilical Cord Blood for GMP-Compliant Autologous Adoptive Cell Transfer Therapy

    Directory of Open Access Journals (Sweden)

    Howard R. Seay

    2017-03-01

    Full Text Available Umbilical cord blood is a traditional and convenient source of cells for hematopoietic stem cell transplantation. Thymic regulatory T cells (Tregs are also present in cord blood, and there is growing interest in the use of autologous Tregs to provide a low-risk, fully human leukocyte antigen (HLA-matched cell product for treating autoimmune diseases, such as type 1 diabetes. Here, we describe a good manufacturing practice (GMP-compatible Treg expansion protocol using fluorescence-activated cell sorting, resulting in a mean 2,092-fold expansion of Tregs over a 16-day culture for a median yield of 1.26 × 109 Tregs from single-donor cryopreserved units. The resulting Tregs passed prior clinical trial release criteria for Treg purity and sterility, including additional rigorous assessments of FOXP3 and Helios expression and epigenetic analysis of the FOXP3 Treg-specific demethylated region (TSDR. Compared with expanded adult peripheral blood Tregs, expanded cord blood Tregs remained more naive, as assessed by continued expression of CD45RA, produced reduced IFN-γ following activation, and effectively inhibited responder T cell proliferation. Immunosequencing of the T cell receptor revealed a remarkably diverse receptor repertoire within cord blood Tregs that was maintained following in vitro expansion. These data support the feasibility of generating GMP-compliant Tregs from cord blood for adoptive cell transfer therapies and highlight potential advantages in terms of safety, phenotypic stability, autoantigen specificity, and tissue distribution.

  18. Foxp3 regulates ratio of Treg and NKT cells in a mouse model of asthma.

    Science.gov (United States)

    Lu, Yanming; Guo, Yinshi; Xu, Linyun; Li, Yaqin; Cao, Lanfang

    2015-05-01

    Chronic inflammatory disorder of the airways causes asthma. Regulatory T cells (Treg cells) and Natural killer T cells (NKT cells) both play critical roles in the pathogenesis of asthma. Activation of Treg cells requires Foxp3, whereas whether Foxp3 may regulate the ratio of Treg and NKT cells to affect asthma is uncertain. In an ovalbumin (OVA)-induced mouse model of asthma, we either increased Treg cells by lentivirus-mediated forced expression of exogenous Foxp3, or increased NKT cells by stimulation with its activator α-GalCer. We found that the CD4+CD25+ Treg cells increased by forced Foxp3 expression, and decreased by α-GalCer, while the CD3+CD161+ NKT cells decreased by forced Foxp3 expression, and increased by α-GalCer. Moreover, forced Foxp3 expression, but not α-GalCer, significantly alleviated the hallmarks of asthma. Furthermore, forced Foxp3 increased levels of IL_10 and TGFβ1, and α-GalCer increased levels of IL_4 and INFγ in the OVA-treated lung. Taken together, our study suggests that Foxp3 may activate Treg cells and suppress NKT cells in asthma. Treg and NKT cells may antagonize the effects of each other in asthma.

  19. Cysticerci Drive Dendritic Cells to Promote In Vitro and In Vivo Tregs Differentiation

    Directory of Open Access Journals (Sweden)

    Laura Adalid-Peralta

    2013-01-01

    Full Text Available Regulatory T cells (Tregs play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the host’s inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC, the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC from healthy human donors, cocultivated with autologous CD4+ naïve cells either in the presence or absence of cysticerci, promoted CD25highFoxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205 was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

  20. Cysticerci drive dendritic cells to promote in vitro and in vivo Tregs differentiation.

    Science.gov (United States)

    Adalid-Peralta, Laura; Arce-Sillas, Asiel; Fragoso, Gladis; Cárdenas, Graciela; Rosetti, Marcos; Casanova-Hernández, Didier; Rangel-Escareño, Claudia; Uribe-Figueroa, Laura; Fleury, Agnes; Sciutto, Edda

    2013-01-01

    Regulatory T cells (Tregs) play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the host's inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC), the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC) from healthy human donors, cocultivated with autologous CD4(+) naïve cells either in the presence or absence of cysticerci, promoted CD25(high)Foxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205) was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

  1. Notch1 Signaling Regulates the Th17/Treg Immune Imbalance in Patients with Psoriasis Vulgaris.

    Science.gov (United States)

    Ma, Lei; Xue, HaiBo; Gao, Tianqin; Gao, MeiLan; Zhang, YuJie

    2018-01-01

    To evaluate the regulating effect of Notch1 signaling on Th17/Treg immune imbalance in psoriasis vulgaris (PV). Notch1, Hes-1, ROR γ t, Foxp3, IL-17, and IL-10 mRNA expression, as well as Th17 and Treg cell percentages in peripheral CD4 + T cells, were detected by real-time quantitative RT-PCR and flow cytometry, and serum concentrations of IL-17 and IL-10 were detected by ELISA in 36 PV patients and 32 healthy controls. Additionally, CD4 + T cells from 12 PV patients were treated with γ -secretase inhibitor DAPT, and the above indexes were measured. PV patients presented distinct Th17/Treg immune imbalance and highly expressed Notch1 and Hes-1 mRNA levels, which were positively correlated with psoriasis area and severity index (PASI) and the ratios of Th17/Treg and ROR γ t/Foxp3. DAPT treatment resulted in the obvious downregulation of Th17 cell percentage in cocultured CD4 + T cells, ROR γ t and IL-17 mRNA levels, and IL-17 concentration in cell-free supernatant from cocultured CD4 + T cells of PV patients in a dose-dependent manner, while there was no significant influence on Treg cell percentage, Foxp3, and IL-10 expression, therefore leading to the recovery of Th17/Treg immune imbalance. Notch1 signaling may contribute to the pathogenesis of PV by regulating Th17/Treg immune imbalance.

  2. Blocking immunosuppression by human Tregs in vivo with antibodies targeting integrin αVβ8.

    Science.gov (United States)

    Stockis, Julie; Liénart, Stéphanie; Colau, Didier; Collignon, Amandine; Nishimura, Stephen L; Sheppard, Dean; Coulie, Pierre G; Lucas, Sophie

    2017-11-21

    Human regulatory T cells (Tregs) suppress other T cells by converting the latent, inactive form of TGF-β1 into active TGF-β1. In Tregs, TGF-β1 activation requires GARP, a transmembrane protein that binds and presents latent TGF-β1 on the surface of Tregs stimulated through their T cell receptor. However, GARP is not sufficient because transduction of GARP in non-Treg T cells does not induce active TGF-β1 production. RGD-binding integrins were shown to activate TGF-β1 in several non-T cell types. Here we show that αVβ8 dimers are present on stimulated human Tregs but not in other T cells, and that antibodies against αV or β8 subunits block TGF-β1 activation in vitro. We also show that αV and β8 interact with GARP/latent TGF-β1 complexes in human Tregs. Finally, a blocking antibody against β8 inhibited immunosuppression by human Tregs in a model of xenogeneic graft-vs.-host disease induced by the transfer of human T cells in immunodeficient mice. These results show that TGF-β1 activation on the surface of human Tregs implies an interaction between the integrin αVβ8 and GARP/latent TGF-β1 complexes. Immunosuppression by human Tregs can be inhibited by antibodies against GARP or against the integrin β8 subunit. Such antibodies may prove beneficial against cancer or chronic infections.

  3. Ocular allergy modulation to hi-dose antigen sensitization is a Treg-dependent process.

    Science.gov (United States)

    Lee, Hyun Soo; Schlereth, Simona; Khandelwal, Payal; Saban, Daniel R

    2013-01-01

    A reproducible method to inhibit allergic immune responses is accomplished with hi-dose Ag sensitization, via intraperitoneal (IP) injection. However, the role of CD4+ CD25+ FoxP3+ T regulatory cells (Treg) in this process is unknown, as is whether such modulation extends to ocular allergy. We therefore determined herein whether hi-dose sensitization modulates ocular allergy, and whether CD4+ CD25+ FoxP3+ Treg are involved. C57BL/6 mice were IP sensitized via low-dose (100 µg) versus hi-dose (1000 µg) ovalbumin (OVA), in aluminum hydroxide (1 mg) and pertussis-toxin (300 ng). Other mice received anti-CD25 Ab (PC61) to ablate Treg during sensitization. In another experiment, Treg from hi-dose sensitized mice were adoptively transferred into low-dose sensitized mice. Once daily OVA challenges were administered. Clinical signs, IgE, T cell cytokines, and eosinophils were assessed. Data revealed that hi-dose, but not low-dose, sensitization led to allergy modulation, indicated by decreased clinical signs, serum IgE levels, Th2 recall responses, and eosinophil recruitment. T cells from hi-dose sensitized mice showed a robust increase in TGF-b production, and Treg from these mice were able to efficiently suppress effector T cell proliferation in vitro. In addition, in vivo Treg ablation in hi-dose sensitized mice revoked allergy modulation. Lastly, Treg from hi-dose sensitized mice were able to adoptively transfer allergy modulation to their low-dose sensitized counterparts. Collectively, these findings indicate that modulation to hi-dose sensitization, which is extended to ocular allergy, occurs in a Treg-dependent manner. In addition, our data suggest that hi-dose sensitization may henceforth facilitate the further examination of CD4+ CD25+ FoxP3+ Treg in allergic disease.

  4. CD11c-expressing cells affect Treg behavior in the meninges during CNS infection1

    Science.gov (United States)

    O’Brien, Carleigh A.; Overall, Christopher; Konradt, Christoph; O’Hara Hall, Aisling C.; Hayes, Nikolas W.; Wagage, Sagie; John, Beena; Christian, David A.; Hunter, Christopher A.; Harris, Tajie H.

    2017-01-01

    Treg cells play an important role in the CNS during multiple infections as well as autoimmune inflammation, but the behavior of this cell type in the CNS has not been explored. In mice, infection with Toxoplasma gondii leads to a Th1-polarized parasite-specific effector T cell response in the brain. Similarly, the Treg cells in the CNS during T. gondii infection are Th1-polarized, exemplified by T-bet, CXCR3, and IFN-γ expression. Unlike effector CD4+ T cells, an MHC Class II tetramer reagent specific for T. gondii did not recognize Treg cells isolated from the CNS. Likewise, TCR sequencing revealed minimal overlap in TCR sequence between effector and regulatory T cells in the CNS. Whereas effector T cells are found in the brain parenchyma where parasites are present, Treg cells were restricted to the meninges and perivascular spaces. The use of intravital imaging revealed that activated CD4+ T cells within the meninges were highly migratory, while Treg cells moved more slowly and were found in close association with CD11c+ cells. To test whether the behavior of Tregs in the meninges is influenced by interactions with CD11c+ cells, mice were treated with anti-LFA-1 antibodies to reduce the number of CD11c+ cells in this space. The anti-LFA-1 treatment led to fewer contacts between Tregs and the remaining CD11c+ cells and increased the speed of Treg cell migration. These data suggest that Treg cells are anatomically restricted within the CNS and the interaction with CD11c+ populations regulates their local behavior during T. gondii infection. PMID:28389591

  5. 3, 3'-Diindolylmethane alleviates steatosis and the progression of NASH partly through shifting the imbalance of Treg/Th17 cells to Treg dominance.

    Science.gov (United States)

    Liu, Yun; She, Weimin; Wang, Fuping; Li, Jing; Wang, Jiyao; Jiang, Wei

    2014-12-01

    This study was designed to discuss the effects of 3, 3'-diindolylmethane (DIM) on methionine-choline-deficient (MCD)-diet induced mouse nonalcoholic steatohepatitis (NASH) and the potential mechanisms. NASH mice were administrated with or without DIM at different concentrations for 8 weeks. Both the in-vivo and in-vitro effects of DIM on Treg/Th17 imbalance during NASH progression were analyzed. The in-vivo blocking of CD25 or IL-17 was performed to respectively deplete respective function of Treg or Th17 subset. Besides, with the assistance of AhR antagonist CH223191 and anti-TLR4 neutralizing antibody, we designed the in-vitro DIM-incubation experiments to discuss the roles of aryl hydrocarbon receptor (AhR) (CYP1A1, CYP1B1) and toll-like receptor 4 (TLR4) on DIM's effects when shifting Treg/Th17 imbalance. Notably, in NASH mouse models, DIM alleviated hepatic steatosis and inflammation, and shifted the Treg/Th17 imbalance from MCD diet-induced Th17 dominance to Treg dominance. In-vitro, DIM not only significantly up-regulated the mRNAs of Foxp3 (Treg-specific) in purified spleen CD4(+) T cells, but also enhanced the immunosuppressive function of these Treg cells. Besides, DIM significantly up-regulated the proteins of CYP1A1 and CYP1B1 whereas down-regulated those of TLR4 on CD4(+) T cells from MCD-diet mice. Moreover, blocking AhR attenuated while blocking TLR4 enhanced the effects of DIM when regulating Treg/Th17 imbalance. Conclusively, DIM could be used as a potential therapeutic candidate to treat NASH based on its dramatic induction of Treg dominance to alleviate intra-hepatic inflammation, suggesting us a clue that the dietary cruciferous vegetables (containing abundant DIM) might exist as a protective factor for patients with NASH-related liver diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. The GARP/Latent TGF-β1 complex on Treg cells modulates the induction of peripherally derived Treg cells during oral tolerance.

    Science.gov (United States)

    Edwards, Justin P; Hand, Timothy W; Morais da Fonseca, Denise; Glass, Deborah D; Belkaid, Yasmine; Shevach, Ethan M

    2016-06-01

    Treg cells can secrete latent TGF-β1 (LTGF-β1), but can also utilize an alternative pathway for transport and expression of LTGF-β1 on the cell surface in which LTGF-β1 is coupled to a distinct LTGF-β binding protein termed glycoprotein A repetitions predominant (GARP)/LRRC32. The function of the GARP/LTGF-β1 complex has remained elusive. Here, we examine in vivo the roles of GARP and TGF-β1 in the induction of oral tolerance. When Foxp3(-) OT-II T cells were transferred to wild-type recipient mice followed by OVA feeding, the conversion of Foxp3(-) to Foxp3(+) OT-II cells was dependent on recipient Treg cells. Neutralization of IL-2 in the recipient mice also abrogated this conversion. The GARP/LTGF-β1 complex on recipient Treg cells, but not dendritic cell-derived TGF-β1, was required for efficient induction of Foxp3(+) T cells and for the suppression of delayed hypersensitivity. Expression of the integrin αvβ8 by Treg cells (or T cells) in the recipients was dispensable for induction of Foxp3 expression. Transient depletion of the bacterial flora enhanced the development of oral tolerance by expanding Treg cells with enhanced expression of the GARP/LTGF-β1 complex. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  7. Human Tregs Made Antigen Specific by Gene Modification: The Power to Treat Autoimmunity and Antidrug Antibodies with Precision

    Directory of Open Access Journals (Sweden)

    Patrick R. Adair

    2017-09-01

    Full Text Available Human regulatory CD4+ T cells (Tregs are potent immunosuppressive lymphocytes responsible for immune tolerance and homeostasis. Since the seminal reports identifying Tregs, vast research has been channeled into understanding their genesis, signature molecular markers, mechanisms of suppression, and role in disease. This research has opened the doors for Tregs as a potential therapeutic for diseases and disorders such as multiple sclerosis, type I diabetes, transplantation, and immune responses to protein therapeutics, like factor VIII. Seminal clinical trials have used polyclonal Tregs, but the frequency of antigen-specific Tregs among polyclonal populations is low, and polyclonal Tregs may risk non-specific immunosuppression. Antigen-specific Treg therapy, which uses genetically modified Tregs expressing receptors specific for target antigens, greatly mitigates this risk. Building on the principles of T-cell receptor cloning, chimeric antigen receptors (CARs, and a novel CAR derivative, called B-cell antibody receptors, our lab has developed different types of antigen-specific Tregs. This review discusses the current research and optimization of gene-modified antigen-specific human Tregs in our lab in several disease models. The preparations and considerations for clinical use of such Tregs also are discussed.

  8. Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP.

    Science.gov (United States)

    Elkord, Eyad; Abd Al Samid, May; Chaudhary, Belal

    2015-08-21

    Regulatory T cells (Tregs) are key players of immune regulation/dysregulation both in physiological and pathophysiological settings. Despite significant advances in understanding Treg function, there is still a pressing need to define reliable and specific markers that can distinguish different Treg subpopulations. Herein we show for the first time that markers of activated Tregs [latency associated peptide (LAP) and glycoprotein A repetitions predominant (GARP, or LRRC32)] are expressed on CD4+FoxP3- T cells expressing Helios (FoxP3-Helios+) in the steady state. Following TCR activation, GARP/LAP are up-regulated on CD4+Helios+ T cells regardless of FoxP3 expression (FoxP3+/-Helios+). We show that CD4+GARP+/-LAP+ Tregs make IL-10 immunosuppressive cytokine but not IFN-γ effector cytokine. Further characterization of FoxP3/Helios subpopulations showed that FoxP3+Helios+ Tregs proliferate in vitro significantly less than FoxP3+Helios- Tregs upon TCR stimulation. Unlike FoxP3+Helios- Tregs, FoxP3+Helios+ Tregs secrete IL-10 but not IFN-γ or IL-2, confirming they are bona fide Tregs with immunosuppressive characteristics. Taken together, Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP, and FoxP3+Helios+ Tregs have more suppressive characteristics, compared with FoxP3+Helios- Tregs. Our work implies that therapeutic modalities for treating autoimmune and inflammatory diseases, allergies and graft rejection should be designed to induce and/or expand FoxP3+Helios+ Tregs, while therapies against cancers or infectious diseases should avoid such expansion/induction.

  9. Treg depletion inhibits efficacy of cancer immunotherapy: implications for clinical trials.

    Directory of Open Access Journals (Sweden)

    James F Curtin

    2008-04-01

    Full Text Available Regulatory T lymphocytes (Treg infiltrate human glioblastoma (GBM; are involved in tumor progression and correlate with tumor grade. Transient elimination of Tregs using CD25 depleting antibodies (PC61 has been found to mediate GBM regression in preclinical models of brain tumors. Clinical trials that combine Treg depletion with tumor vaccination are underway to determine whether transient Treg depletion can enhance anti-tumor immune responses and improve long term survival in cancer patients.Using a syngeneic intracrabial glioblastoma (GBM mouse model we show that systemic depletion of Tregs 15 days after tumor implantation using PC61 resulted in a decrease in Tregs present in tumors, draining lymph nodes and spleen and improved long-term survival (50% of mice survived >150 days. No improvement in survival was observed when Tregs were depleted 24 days after tumor implantation, suggesting that tumor burden is an important factor for determining efficacy of Treg depletion in clinical trials. In a T cell dependent model of brain tumor regression elicited by intratumoral delivery of adenoviral vectors (Ad expressing Fms-like Tyrosine Kinase 3 ligand (Flt3L and Herpes Simplex Type 1-Thymidine Kinase (TK with ganciclovir (GCV, we demonstrate that administration of PC61 24 days after tumor implantation (7 days after treatment inhibited T cell dependent tumor regression and long term survival. Further, depletion with PC61 completely inhibited clonal expansion of tumor antigen-specific T lymphocytes in response to the treatment.Our data demonstrate for the first time, that although Treg depletion inhibits the progression/eliminates GBM tumors, its efficacy is dependent on tumor burden. We conclude that this approach will be useful in a setting of minimal residual disease. Further, we also demonstrate that Treg depletion, using PC61 in combination with immunotherapy, inhibits clonal expansion of tumor antigen-specific T cells, suggesting that new, more

  10. Thioredoxin induces Tregs to generate an immunotolerant tumor microenvironment in metastatic melanoma

    Science.gov (United States)

    Wang, Xiaogang; Dong, Haisheng; Li, Qi; Li, Yingxian; Hong, An

    2015-01-01

    Metastatic melanoma is a highly aggressive cancer that is very difficult to treat. Additionally, the antitumor immune reaction of melanoma is still unclear. Here we demonstrate an association between the expression and secretion of the antioxidant protein thioredoxin (TRX) and increasing tumor stage and metastasis in melanoma. To elucidate the role of TRX in melanoma, we assessed the correlation of TRX expression with different disease parameters in melanoma. We also examined the in vitro and in vivo effects of modulating TRX levels in melanoma cells using various methods of TRX depletion and augmentation. We further explored the effects of TRX on the cytokine milieu and the ability of TRX to regulate the proportion and specific activities of T-cell populations. We demonstrate that TRX expression correlates with Treg representation in clinical samples and, that modulation of TRX influences the induction of Tregs and the generation of an immunotolerant cytokine profile in mouse serum. Using a murine metastatic melanoma model, we identified a tumor immunoevasion mechanism whereby melanoma cell-secreted TRX enhances Treg infiltration. TRX displays chemotactic effects in recruiting Tregs, stimulates the conversion of conventional T cells to Tregs, and confers survival advantage to Tregs in the tumor microenvironment. In turn, this increase of Tregs generates immunotolerance in tissues and therefore decreases antitumor immune reactions. These results elucidate a mechanism by which TRX promotes metastatic melanoma in part through Treg recruitment to inhibit T-cell antitumor effects and suggest that TRX antibody may be useful in the clinic as a therapy against melanoma. PMID:26405597

  11. The Treg/Th17 axis: A dynamic balance regulated by the gut microbiome

    Directory of Open Access Journals (Sweden)

    Sara eOmenetti

    2015-12-01

    Full Text Available T-helper 17 (Th17 and T-regulatory (Treg cells are frequently found at barrier surfaces, particularly within the intestinal mucosa, where they function to protect the host from pathogenic microorganisms and to restrain excessive effector T-cell responses, respectively. Despite their differing functional properties, Th17 cells and Tregs share similar developmental requirements. In fact, the fate of antigen-naïve T-cells to either Th17 or Treg lineages is finely regulated by key mediators, including TGFβ, IL-6 and all-trans retinoic acid (RA. Importantly, the intestinal microbiome also provides immunostimulatory signals, which can activate innate, and downstream adaptive, immune responses. Specific components of the gut microbiome have been implicated in the production of proinflammatory cytokines by innate immune cells, such as IL-6, IL-23, IL-1β, and the subsequent generation and expansion of Th17 cells. Similarly, commensal bacteria and their metabolites can also promote the generation of intestinal Tregs that can actively induce mucosal tolerance. As such, dysbiosis of the gut microbiome may not solely represent a consequence of gut inflammation, but rather shape the Treg/Th17 commitment and influence susceptibility to inflammatory bowel disease (IBD. In this review, we discuss Treg and Th17 cell plasticity, its dynamic regulation by the microbiome, and highlight its impact on intestinal homeostasis and disease.

  12. A cluster of coregulated genes determines TGF-β–induced regulatory T-cell (Treg) dysfunction in NOD mice

    Science.gov (United States)

    D'Alise, Anna Morena; Ergun, Ayla; Hill, Jonathan A.; Mathis, Diane; Benoist, Christophe

    2011-01-01

    Foxp3+ regulatory T cells (Tregs) originate in the thymus, but the Treg phenotype can also be induced in peripheral lymphoid organs or in vitro by stimulation of conventional CD4+ T cells with IL-2 and TGF-β. There have been divergent reports on the suppressive capacity of these TGF-Treg cells. We find that TGF-Tregs derived from diabetes-prone NOD mice, although expressing normal Foxp3 levels, are uniquely defective in suppressive activity, whereas TGF-Tregs from control strains (B6g7) or ex vivo Tregs from NOD mice all function normally. Most Treg-typical transcripts were shared by NOD or B6g7 TGF-Tregs, except for a small group of differentially expressed genes, including genes relevant for suppressive activity (Lrrc32, Ctla4, and Cd73). Many of these transcripts form a coregulated cluster in a broader analysis of T-cell differentiation. The defect does not map to idd3 or idd5 regions. Whereas Treg cells from NOD mice are normal in spleen and lymph nodes, the NOD defect is observed in locations that have been tied to pathogenesis of diabetes (small intestine lamina propria and pancreatic lymph node). Thus, a genetic defect uniquely affects a specific Treg subpopulation in NOD mice, in a manner consistent with a role in determining diabetes susceptibility. PMID:21543717

  13. A cluster of coregulated genes determines TGF-beta-induced regulatory T-cell (Treg) dysfunction in NOD mice.

    Science.gov (United States)

    D'Alise, Anna Morena; Ergun, Ayla; Hill, Jonathan A; Mathis, Diane; Benoist, Christophe

    2011-05-24

    Foxp3(+) regulatory T cells (Tregs) originate in the thymus, but the Treg phenotype can also be induced in peripheral lymphoid organs or in vitro by stimulation of conventional CD4(+) T cells with IL-2 and TGF-β. There have been divergent reports on the suppressive capacity of these TGF-Treg cells. We find that TGF-Tregs derived from diabetes-prone NOD mice, although expressing normal Foxp3 levels, are uniquely defective in suppressive activity, whereas TGF-Tregs from control strains (B6g7) or ex vivo Tregs from NOD mice all function normally. Most Treg-typical transcripts were shared by NOD or B6g7 TGF-Tregs, except for a small group of differentially expressed genes, including genes relevant for suppressive activity (Lrrc32, Ctla4, and Cd73). Many of these transcripts form a coregulated cluster in a broader analysis of T-cell differentiation. The defect does not map to idd3 or idd5 regions. Whereas Treg cells from NOD mice are normal in spleen and lymph nodes, the NOD defect is observed in locations that have been tied to pathogenesis of diabetes (small intestine lamina propria and pancreatic lymph node). Thus, a genetic defect uniquely affects a specific Treg subpopulation in NOD mice, in a manner consistent with a role in determining diabetes susceptibility.

  14. Time-resolved transcriptome and proteome landscape of human regulatory T cell (Treg) differentiation reveals novel regulators of FOXP3

    KAUST Repository

    Schmidt, Angelika

    2018-04-27

    BackgroundRegulatory T cells (Tregs) expressing the transcription factor FOXP3 are crucial mediators of self-tolerance, preventing autoimmune diseases but possibly hampering tumor rejection. Clinical manipulation of Tregs is of great interest, and first-in-man trials of Treg transfer have achieved promising outcomes. Yet, the mechanisms governing induced Treg (iTreg) differentiation and the regulation of FOXP3 are incompletely understood.ResultsTo gain a comprehensive and unbiased molecular understanding of FOXP3 induction, we performed time-series RNA sequencing (RNA-Seq) and proteomics profiling on the same samples during human iTreg differentiation. To enable the broad analysis of universal FOXP3-inducing pathways, we used five differentiation protocols in parallel. Integrative analysis of the transcriptome and proteome confirmed involvement of specific molecular processes, as well as overlap of a novel iTreg subnetwork with known Treg regulators and autoimmunity-associated genes. Importantly, we propose 37 novel molecules putatively involved in iTreg differentiation. Their relevance was validated by a targeted shRNA screen confirming a functional role in FOXP3 induction, discriminant analyses classifying iTregs accordingly, and comparable expression in an independent novel iTreg RNA-Seq dataset.ConclusionThe data generated by this novel approach facilitates understanding of the molecular mechanisms underlying iTreg generation as well as of the concomitant changes in the transcriptome and proteome. Our results provide a reference map exploitable for future discovery of markers and drug candidates governing control of Tregs, which has important implications for the treatment of cancer, autoimmune, and inflammatory diseases.

  15. The Alpha-Melanocyte Stimulating Hormone Induces Conversion of Effector T Cells into Treg Cells

    Directory of Open Access Journals (Sweden)

    Andrew W. Taylor

    2011-01-01

    Full Text Available The neuropeptide alpha-melanocyte stimulating hormone (α-MSH has an important role in modulating immunity and homeostasis. The production of IFN-γ by effector T cells is suppressed by α-MSH, while TGF-β production is promoted in the same cells. Such α-MSH-treated T cells have immune regulatory activity and suppress hypersensitivity, autoimmune diseases, and graft rejection. Previous characterizations of the α-MSH-induced Treg cells showed that the cells are CD4+ T cells expressing the same levels of CD25 as effector T cells. Therefore, we further analyzed the α-MSH-induced Treg cells for expression of effector and regulatory T-cell markers. Also, we examined the potential for α-MSH-induced Treg cells to be from the effector T-cell population. We found that the α-MSH-induced Treg cells are CD25+  CD4+ T cells that share similar surface markers as effector T cells, except that they express on their surface LAP. Also, the α-MSH treatment augments FoxP3 message in the effector T cells, and α-MSH induction of regulatory activity was limited to the effector CD25+ T-cell population. Therefore, α-MSH converts effector T cells into Treg cells, which suppress immunity targeting specific antigens and tissues.

  16. The Correlation of Regulatory T (TReg and Vitamin D3 in Pediatric Nephrotic Syndrome

    Directory of Open Access Journals (Sweden)

    Yunika Nurtyas

    2018-01-01

    Full Text Available Nephrotic syndrome (NS is an autoimmune disease that correlates to the imbalance of regulatory T cells (TReg. This study was aimed to investigate the effect of vitamin D as adjuvant therapy of TReg population in pediatric nephrotic syndrome. This study was designed randomized clinical trial, double blind, with pre- and post-test control groups involving 15 subjects newly diagnosed with NS. Subjects were divided into 2 groups, namely K1 for group treated with prednisone+vitamin D and K2 group for prednisone treatment only. The population of TReg in peripheral blood mononuclear cells (PBMC was analyzed using flowcytometry. Vitamin D serum level was measured through ELISA method. Results showed that there was a significant elevation of TReg (independent t-test, p = 0.010 in K1 group, which was higher than in K2 group. The Pearson test in the K1 group showed that vitamin D level was positively correlated with TReg (p = 0.039, r = 0.779.

  17. Effect of thymosin alpha-1 on subpopulations of Th1, Th2, Th17, and regulatory T cells (Tregs) in vitro

    International Nuclear Information System (INIS)

    Yang, Xia; Qian, Feng; He, Hai-Yang; Liu, Kai-Jun; Lan, Yuan-Zhi; Ni, Bing; Tian, Yi; Fu, Xiao-Lan; Zhang, Ji; Shen, Zi-Gang; Li, Jian; Yin, Yi; Li, Jin-Tao; Wu, Yu-Zhang

    2011-01-01

    Thymosin alpha 1 (Tα1) has been shown to have beneficial effects on numerous immune system parameters, but little is known about the effects of Tα1 on patients with gastric carcinoma. The objective of this study was to determine the effect of Tα1 on subpopulations of Th1, Th2, Th17, and regulatory T cells (Tregs) in vitro, and to evaluate its efficacy as an immunoregulatory factor in patients with gastric carcinoma. We compared the effect of Tα1 on the frequency of CD4 + and CD8 + T cells, especially the CD4 + CD25 + Foxp3 + Tregs in peripheral blood mononuclear cells (PBMCs) from gastric carcinoma patients (N = 35) and healthy donors (N = 22). We also analyzed the changes in the proliferation of PBMCs in response to treatment with Tα1, and examined the production of Th1, Th2, and Th17 cytokines by PBMCs and tumor-infiltrating lymphocytes. The treatment of PBMCs from gastric cancer patients, with Tα1 (50 µg/mL) alone increased the percentage of CD4+CD25+Foxp3+ (suppressive antitumor-specific Tregs) from 1.68 ± 0.697 to 2.19 ± 0.795% (P < 0.05). Our results indicate that Tα1 increases the percentage of Tregs and IL-1β, TNF-α, and IL-6 in vitro

  18. Effect of thymosin alpha-1 on subpopulations of Th1, Th2, Th17, and regulatory T cells (Tregs) in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xia [Institute of Immunology,Third Military Medical University, Chongqing (China); Qian, Feng [Department of General Surgery, Southwest Hospital, Third Military Medical University, Chongqing (China); He, Hai-Yang; Liu, Kai-Jun [Institute of Immunology,Third Military Medical University, Chongqing (China); Lan, Yuan-Zhi [Department of General Surgery, Southwest Hospital, Third Military Medical University, Chongqing (China); Ni, Bing; Tian, Yi; Fu, Xiao-Lan; Zhang, Ji; Shen, Zi-Gang; Li, Jian; Yin, Yi; Li, Jin-Tao; Wu, Yu-Zhang [Institute of Immunology,Third Military Medical University, Chongqing (China)

    2011-12-02

    Thymosin alpha 1 (Tα1) has been shown to have beneficial effects on numerous immune system parameters, but little is known about the effects of Tα1 on patients with gastric carcinoma. The objective of this study was to determine the effect of Tα1 on subpopulations of Th1, Th2, Th17, and regulatory T cells (Tregs) in vitro, and to evaluate its efficacy as an immunoregulatory factor in patients with gastric carcinoma. We compared the effect of Tα1 on the frequency of CD4{sup +} and CD8{sup +} T cells, especially the CD4{sup +}CD25{sup +}Foxp3{sup +} Tregs in peripheral blood mononuclear cells (PBMCs) from gastric carcinoma patients (N = 35) and healthy donors (N = 22). We also analyzed the changes in the proliferation of PBMCs in response to treatment with Tα1, and examined the production of Th1, Th2, and Th17 cytokines by PBMCs and tumor-infiltrating lymphocytes. The treatment of PBMCs from gastric cancer patients, with Tα1 (50 µg/mL) alone increased the percentage of CD4+CD25+Foxp3+ (suppressive antitumor-specific Tregs) from 1.68 ± 0.697 to 2.19 ± 0.795% (P < 0.05). Our results indicate that Tα1 increases the percentage of Tregs and IL-1β, TNF-α, and IL-6 in vitro.

  19. In-vitro inhibition of IFNγ+ iTreg mediated by monoclonal antibodies against cell surface determinants essential for iTreg function

    Directory of Open Access Journals (Sweden)

    Daniel Volker

    2012-08-01

    Full Text Available Abstract Background IFNγ-producing CD4+CD25+Foxp3+ PBL represent a subtype of iTreg that are associated with good long-term graft outcome in renal transplant recipients and suppress alloresponses in-vitro. To study the mechanism of immunosuppression, we attempted to block cell surface receptors and thereby inhibited the function of this iTreg subset in-vitro using monoclonal antibodies and recombinant proteins. Methods PBL of healthy control individuals were stimulated polyclonally in-vitro in the presence of monoclonal antibodies or recombinant proteins against/of CD178, CD152, CD279, CD28, CD95, and HLA-DR. Induction of IFNγ+ iTreg and proliferation of effector cells was determined using four-color fluorescence flow cytometry. Blockade of iTreg function was analyzed using polyclonally stimulated co-cultures with separated CD4+CD25+CD127-IFNγ+ PBL. Results High monoclonal antibody concentrations inhibited the induction of CD4+CD25+Foxp3+IFNγ+ PBL (anti-CD152, anti-CD279, anti-CD95: p +CD25+CD127-IFNγ+ PBL (anti-CD178, anti-CD152, anti-CD279, anti-CD95: p +CD25+Foxp3+IFNγ+ PBL (rCD152 and rCD95: p +CD25+CD127-IFNγ+ PBL showed lower cell proliferation than co-cultures with CD4+CD25+CD127-IFNγ- PBL (p +CD25+CD127-IFNγ- PBL-containing co-cultures in the presence of monoclonal antibody (anti-CD28, anti-CD152, anti-CD279: p +CD25+CD127-IFNγ+ PBL (with the exception anti-CD28 monoclonal antibody: p +CD25+CD127-IFNγ- PBL but do not efficiently block suppressive iTreg function in co-cultures with CD4+CD25+CD127-IFNγ+ PBL. Conclusions CD178, CD152, CD279, CD28, CD95, and HLA-DR determinants are important for induction and suppressive function of IFNγ+ iTreg.

  20. Multifaceted effects of synthetic TLR2 ligand and Legionella pneumophilia on Treg-mediated suppression of T cell activation

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    Sutmuller Roger PM

    2011-03-01

    Full Text Available Abstract Background Regulatory T cells (Treg play a crucial role in maintaining immune homeostasis and self-tolerance. The immune suppressive effects of Tregs should however be limited in case effective immunity is required against pathogens or cancer cells. We previously found that the Toll-like receptor 2 (TLR2 agonist, Pam3CysSK4, directly stimulated Tregs to expand and temporarily abrogate their suppressive capabilities. In this study, we evaluate the effect of Pam3CysSK4 and Legionella pneumophila, a natural TLR2 containing infectious agent, on effector T (Teff cells and dendritic cells (DCs individually and in co-cultures with Tregs. Results TLR2 agonists can directly provide a co-stimulatory signal inducing enhanced proliferation and cytokine production of naive CD4+ Teff cells. With respect to cytokine production, DCs appear to be most sensitive to low amounts of TLR agonists. Using wild type and TLR2-deficient cells in Treg suppression assays, we accordingly show that all cells (e.g. Treg, Teff cells and DCs contributed to overcome Treg-mediated suppression of Teff cell proliferation. Furthermore, while TLR2-stimulated Tregs readily lost their ability to suppress Teff cell proliferation, cytokine production by Teff cells was still suppressed. Similar results were obtained upon stimulation with TLR2 ligand containing bacteria, Legionella pneumophila. Conclusions These findings indicate that both synthetic and natural TLR2 agonists affect DCs, Teff cells and Treg directly, resulting in multi-modal modulation of Treg-mediated suppression of Teff cells. Moreover, Treg-mediated suppression of Teff cell proliferation is functionally distinct from suppression of cytokine secretion.

  1. Establishment of a rat model of early-stage liver failure and Th17/Treg imbalance

    OpenAIRE

    LI Dong; LU Zhonghua; GAN Jianhe

    2016-01-01

    ObjectiveTo investigate the methods for establishing a rat model of early-stage liver failure and the changes in Th17, Treg, and Th17/Treg after dexamethasone and thymosin interventions. MethodsA total of 64 rats were randomly divided into carbon tetrachloride (CCl4) group and endotoxin [lipopolysaccharide (LPS)]/D-galactosamine (D-GalN) combination group to establish the rat model of early-stage liver failure. The activities of the rats and changes in liver function and whole blood Th17 and ...

  2. SF Treg cells transcribing high levels of Bcl-2 and microRNA-21 demonstrate limited apoptosis in RA

    NARCIS (Netherlands)

    van der Geest, Kornelis S. M.; Smigielska, Katarzyna; Park, Ji-Ah; Abdulahad, Wayel H.; Kim, Hye-Won; Kroesen, Bart-Jan; van den Berg, Anke; Boots, Annemieke M. H.; Lee, Eun-Bong; Brouwer, Elisabeth

    Objective. The aim of this study was to investigate the turnover of Treg cells in the SF of RA patients. Methods. Treg cells were enumerated in peripheral blood and SF of RA patients and analysed by flow cytometry for expression of the proliferation marker Ki-67 and binding of the apoptosis marker

  3. GILZ Promotes Production of Peripherally Induced Treg Cells and Mediates the Crosstalk between Glucocorticoids and TGF-β Signaling

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    Oxana Bereshchenko

    2014-04-01

    Full Text Available Regulatory T (Treg cells expressing the transcription factor forkhead box P3 (FoxP3 control immune responses and prevent autoimmunity. Treatment with glucocorticoids (GCs has been shown to increase Treg cell frequency, but the mechanisms of their action on Treg cell induction are largely unknown. Here, we report that glucocorticoid-induced leucine zipper (GILZ, a protein induced by GCs, promotes Treg cell production. In mice, GILZ overexpression causes an increase in Treg cell number, whereas GILZ deficiency results in impaired generation of peripheral Treg cells (pTreg, associated with increased spontaneous and experimental intestinal inflammation. Mechanistically, we found that GILZ is required for GCs to cooperate with TGF-β in FoxP3 induction, while it enhances TGF-β signaling by binding to and promoting Smad2 phosphorylation and activation of FoxP3 expression. Thus, our results establish an essential GILZ-mediated link between the anti-inflammatory action of GCs and the regulation of TGF-β-dependent pTreg production.

  4. Functional and genomic analyses of FOXP3-transduced Jurkat-T cells as regulatory T (Treg)-like cells

    International Nuclear Information System (INIS)

    Kim, Joon-Young; Kim, Han-Jong; Hurt, Elaine M.; Chen, Xin; Howard, O.M. Zack; Farrar, William L.

    2007-01-01

    FOXP3, a forkhead transcription factor is essential for the development and function of CD4 + CD25 + regulatory T cells (Tregs). In contrast to conversion of murine naive T cells to Tregs by transduction of Foxp3, it is controversial whether ectopic expression of FOXP3 in human CD4 + T cells is sufficient for acquisition of suppressive activity. Here, we show that retroviral transduction of FOXP3 induces a Treg phenotype in human leukemic CD4 + Jurkat-T cells, evidenced by increased expression of Treg-associated cell surface markers as well as inhibition of cytokine production. Furthermore, FOXP3-transduced Jurkat-T cells suppress the proliferation of human CD4 + CD25 - T cells. Additionally, DNA microarray analysis identifies Treg-related genes regulated by FOXP3. Our study demonstrates that enforced expression of FOXP3 confers Treg-like properties on Jurkat-T cells, which can be a convenient and efficient Treg-like cell model for further study to identify Treg cell surface markers and target genes regulated by FOXP3

  5. Methionine enkephalin (MENK) inhibits tumor growth through regulating CD4+Foxp3+ regulatory T cells (Tregs) in mice.

    Science.gov (United States)

    Li, Xuan; Meng, Yiming; Plotnikoff, Nicolas P; Youkilis, Gene; Griffin, Noreen; Wang, Enhua; Lu, Changlong; Shan, Fengping

    2015-01-01

    Methionine enkephalin (MENK), an endogenous neuropeptide, plays an crucial role in both neuroendocrine and immune systems. CD4+Foxp3+ regulatory T cells (Tregs) are identified as a major subpopulation of T lymphocytes in suppressing immune system to keep balanced immunity. The aim of this research work was to elucidate the mechanisms via which MENK interacts with Tregs in cancer situation. The influence of MENK on transforming growth factor-β (TGF-β) mediated conversion from naïve CD4+CD25- T cells to CD4+CD25+ Tregs was determined and the data from flow cytometry (FCM) analysis indicated that MENK effectively inhibited the expression of Foxp3 during the process of TGF-βinduction. Furthermore, this inhibiting process was accompanied by diminishing phosphorylation and nuclear translocation of Smad2/3, confirmed by western blot (WB) analysis and immunofluorescence (IF) at molecular level. We established sarcoma mice model with S180 to investigate whether MENK could modulate Tregs in tumor circumstance. Our findings showed that MENK delayed the development of tumor in S180 tumor bearing mice and down-regulated level of Tregs. Together, these novel findings reached a conclusion that MENK could inhibit Tregs activity directly and retard tumor development through down-regulating Tregs in mice. This work advances the deepening understanding of the influence of MENK on Tregs in cancer situation, and relation of MENK with immune system, supporting the implication of MENK as a new strategy for cancer immunotherapy.

  6. Increased IL-35 producing Tregs and CD19+IL-35+ cells are associated with disease progression in leprosy patients.

    Science.gov (United States)

    Tarique, Mohd; Saini, Chaman; Naqvi, Raza Ali; Khanna, Neena; Rao, D N

    2017-03-01

    The clinical forms of leprosy consist of a spectrum that reflects the host's immune response to the M. leprae; it provides an ideal model to study the host pathogen interaction and immunological dysregulation in humans. IL-10 and TGF-β producing Tregs are high in leprosy patients and responsible for immune suppression and M. leprae specific T cells anergy. In leprosy, involvement of IL-35 producing Tregs and Bregs remain unstudied. To study the role of IL-35 producing Tregs and Bregs in the human leprosy. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA) for 48h. Intracellular cytokine IL-35 was evaluated in CD4 + CD25 + Tregs, CD19 + cells by FACS. Expression of PD-1 on CD4 + CD25 + Tregs, CD19 + cells and its ligand (PD-L1) on B cells, CD11c cells were evaluated by flow cytometry (FACS). Serum IL-35 level was estimated by ELISA. The frequency of IL-35 producing Tregs and Bregs cells were found to be high in leprosy patients (pleprosy patients. This study point out a shift in our understanding of the immunological features that mediate and regulate the immune suppression and the disease progression in leprosy patients with a new paradigm (IL-35 producing Tregs and Bregs) that is beyond TGF-β and IL-10 producing Treg cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Treg cell-IgA axis in maintenance of host immune homeostasis with microbiota

    OpenAIRE

    Feng, Ting; Elson, Charles O.; Cong, Yingzi

    2010-01-01

    The intestine is the home to a vast diversity of microbiota and a complex of mucosal immune system. Multiple regulatory mechanisms control host immune responses to microbiota and maintain intestinal immune homeostasis. This mini review will provide evidence indicating a Treg cell-IgA axis and such axis playing a major role in maintenance of intestinal homeostasis.

  8. CRISPR and personalized Treg therapy: new insights into the treatment of rheumatoid arthritis.

    Science.gov (United States)

    Safari, Fatemeh; Farajnia, Safar; Arya, Maryam; Zarredar, Habib; Nasrolahi, Ava

    2018-06-01

    Rheumatoid arthritis (RA), as one of the most disabling autoimmune diseases, is a common health problem that progressively reduces the life quality of patients. Although various biologics have been introduced for RA, attempts to establish an efficient long-term therapies failed due to the heterogeneity of this disease. In the last decade, immunomodulatory approaches such as T cell adoptive therapy have been developed for controlling autoimmunity. Regulatory T cells (Tregs), the major self-tolerance mediator, are crucial for down-regulation of aberrant immune stimulations. Hence, recruiting ex vivo Tregs emerged as a promising therapy for a variety of autoimmune diseases. The major bottleneck of the Treg adoptive therapy is maintaining the in vivo stability and plasticity of these fascinating cells. Recent progress in genome editing technology clustered regularly interspaced short palindromic repeats (CRISPR) in combination with CRISPR-associated (Cas) 9 system provided a new solution for this bottleneck. The present paper discusses RA pathogenesis and the potential application of new developments in CRISPR-mediated Treg genome editing in personalized therapy of RA.

  9. Depletion of Treg cells augments the therapeutic effect of cancer vaccines

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2006-01-01

    Roč. 52, č. 6 (2006), s. 202-204 ISSN 0015-5500 Grant - others:EU-FP6-Clinigene(XE) 018933 Institutional research plan: CEZ:AV0Z50520514 Keywords : Treg cells * cancer vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.387, year: 2006

  10. [Th17 and Treg cell levels in patients with sarcoidosis and their relation to disease activation].

    Science.gov (United States)

    Weng, Yue-song; Wang, Hua-ying; Lv, Ding-feng; Fu, Zhong-ming; Yu, Wan-jun

    2015-03-01

    To investigate the Th17 cell and Treg cell levels in patients with sarcoidosis, and their relation to disease activation and glucocorticoids treatment. Twenty-three sarcoidosis patients admitted in Yinzhou People's Hospital from January 2009 to December 2013 and 25 healthy subjects (controls) were included in this study. The blood samples and bronchoalveolar lavage fluid (BALF) samples were collected in all patients before and after glucocorticoids treatment. The serum angiotensin converting enzyme (SACE) levels were detected. The percentages of Th17 cells and Treg cells in peripheral blood and BALF were determined by flow cytometry, the concentrations of cytokines in serum and supernatants of BALF were measured by enzyme-linked immunosorbent assay (ELISA). The levels of ROR-γt and Foxp3 mRNA transcripts in peripheral blood mononuclear cells (PBMC) were determined by real-time quantitative PCR. The potential correlation between the percentages of Th17 or Treg cells and SACE levels was evaluated. Compared with healthy controls, significantly higher frequencies of Th17 cells (4.34%±0.89% vs 1.60% ± 0.42%), lower frequencies of Treg cells (1.28% ± 0.37% vs 3.39% ± 0.50%) in peripheral blood were observed. Higher level of ROR-γt mRNA (21.31 ± 3.55 vs 3.63 ± 1.00) and lower level of Foxp3 mRNA (1.60 ± 0.24 vs 3.12 ± 0.76) in peripheral blood were detected in sarcoidosis patients in active stage (before glucocorticoids treatment) (all PSACE (r= 0.781). The imbalance of Th17 cells and Treg cells in peripheral blood and airway may be involved in the pathogenesis of sarcoidosis, which was associated with the activity of disease, and the treatment of glucocorticoids may achieve a therapeutic effect by correcting the immune imbalance.

  11. Follicular Lymphoma Tregs Have a Distinct Transcription Profile Impacting Their Migration and Retention in the Malignant Lymph Node.

    Directory of Open Access Journals (Sweden)

    Hristina Nedelkovska

    Full Text Available We have previously shown that regulatory T cells (Tregs infiltrating follicular lymphoma lymph nodes are quantitatively and qualitatively different than those infiltrating normal and reactive nodes. To gain insight into how such Treg populations differ, we performed RNA sequence (RNAseq analyses on flow sorted Tregs from all three sources. We identify several molecules that could contribute to the observed increased suppressive capacity of follicular lymphoma nodal tregs, including upregulation of CTLA-4, IL-10, and GITR, all confirmed by protein expression. In addition, we identify, and confirm functionally, a novel mechanism by which Tregs target to and accumulate within a human tumor microenvironment, through the down regulation of S1PR1, SELL (L-selectin and CCR7, potentially resulting in greater lymph node retention. In addition we identify and confirm functionally the upregulation of the chemokine receptor CXCR5 as well as the secretion of the chemokines CXCL13 and IL-16 demonstrating the unique ability of the follicular derived Tregs to localize and accumulate within not only the malignant lymph node, but also localize and accumulate within the malignant B cell follicle itself. Such findings offer significant new insights into how follicular lymphoma nodal Tregs may contribute to the biology of follicular lymphoma and identify several novel therapeutic targets.

  12. Spatially selective depleting tumor-associated negative regulatory T-(Treg) cells with near infrared photoimmunotherapy (NIR-PIT): A new cancer immunotherapy (Conference Presentation)

    Science.gov (United States)

    Kobayashi, Hisataka

    2017-02-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new type of molecularly-targeted photo-therapy based on conjugating a near infrared silica-phthalocyanine dye, IR700, to a monoclonal antibody (MAb) targeting target-specific cell-surface molecules. When exposed to NIR light, the conjugate rapidly induces a highly-selective cell death only in receptor-positive, MAb-IR700-bound cells. Current immunotherapies for cancer seek to modulate the balance among different immune cell populations, thereby promoting anti-tumor immune responses. However, because these are systemic therapies, they often cause treatment-limiting autoimmune adverse effects. It would be ideal to manipulate the balance between suppressor and effector cells within the tumor without disturbing homeostasis elsewhere in the body. CD4+CD25+Foxp3+ regulatory T cells (Tregs) are well-known immune-suppressor cells that play a key role in tumor immuno-evasion and have been the target of systemic immunotherapies. We used CD25-targeted NIR-PIT to selectively deplete Tregs, thus activating CD8+ T and NK cells and restoring local anti-tumor immunity. This not only resulted in regression of the treated tumor but also induced responses in separate untreated tumors of the same cell-line derivation. We conclude that CD25-targeted NIR-PIT causes spatially selective depletion of Tregs, thereby providing an alternative approach to cancer immunotherapy that can treat not only local tumors but also distant metastatic tumors.

  13. Cell banking for regulatory T cell-based therapy: strategies to overcome the impact of cryopreservation on the Treg viability and phenotype.

    Science.gov (United States)

    Gołąb, Karolina; Grose, Randall; Placencia, Veronica; Wickrema, Amittha; Solomina, Julia; Tibudan, Martin; Konsur, Evelyn; Ciepły, Kamil; Marek-Trzonkowska, Natalia; Trzonkowski, Piotr; Millis, J Michael; Fung, John; Witkowski, Piotr

    2018-02-09

    The first clinical trials with adoptive Treg therapy have shown safety and potential efficacy. Feasibility of such therapy could be improved if cells are cryopreserved and stored until optimal timing for infusion. Herein, we report the evaluation of two cell-banking strategies for Treg therapy: 1) cryopreservation of CD4 + cells for subsequent Treg isolation/expansion and 2) cryopreservation of ex-vivo expanded Tregs (CD4 + CD25 hi CD127 lo/- cells). First, we checked how cryopreservation affects cell viability and Treg markers expression. Then, we performed Treg isolation/expansion with the final products release testing. We observed substantial decrease in cell number recovery after thawing and overnight culture. This observation might be explained by the high percentage of necrotic and apoptotic cells found just after thawing. Furthermore, we noticed fluctuations in percentage of CD4 + CD25 hi CD127 - and CD4 + FoxP3 + cells obtained from cryopreserved CD4 + as well as Treg cells. However, after re-stimulation Tregs expanded well, presented a stable phenotype and fulfilled the release criteria at the end of expansions. Cryopreservation of CD4 + cells for subsequent Treg isolation/expansion and cryopreservation of expanded Tregs with re-stimulation and expansion after thawing, are promising solutions to overcome detrimental effects of cryopreservation. Both of these cell-banking strategies for Treg therapy can be applied when designing new clinical trials.

  14. Malignant Tregs express low molecular splice forms of FOXP3 in Sézary syndrome

    DEFF Research Database (Denmark)

    Krejsgaard, T; Gjerdrum, L M; Ralfkiaer, E

    2008-01-01

    Sézary syndrome (SS) is an aggressive variant of cutaneous T-cell lymphoma. During disease progression, immunodeficiency develops; however, the underlying molecular and cellular mechanisms are not fully understood. Here, we study the regulatory T cell (Treg) function and the expression of FOXP3...... in SS. We demonstrate that malignant T cells in 8 of 15 patients stain positive with an anti-FOXP3 antibody. Western blotting analysis shows expression of two low molecular splice forms of FOXP3, but not of wild-type (wt) FOXP3. The malignant T cells produce interleukin-10 and TGF-beta and suppress...... the growth of non-malignant T cells. The Treg phenotype and the production of suppressive cytokines are driven by aberrant activation of Jak3 independent of the FOXP3 splice forms. In contrast to wt FOXP3, the low molecular splice forms of FOXP3 have no inhibitory effect on nuclear factor-kappaB (NF...

  15. Depletion of Treg cells inhibits minimal residual disease after surgery of HPV16-associated tumours

    Czech Academy of Sciences Publication Activity Database

    Šímová, Jana; Bubeník, Jan; Bieblová, Jana; Rosalia, Rodney Alexander; Frič, Jan; Reiniš, Milan

    2006-01-01

    Roč. 29, č. 6 (2006), s. 1567-1571 ISSN 1019-6439 R&D Projects: GA ČR(CZ) GA301/04/0492 EU Projects: European Commission(XE) 18933 - CLINIGENE Grant - others:Liga proti rakovině(CZ) XX Institutional research plan: CEZ:AV0Z50520514 Keywords : HPV 16 * residual tumour disease * Treg cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.556, year: 2006

  16. Immune response to Bifidobacterium bifidum strains support Treg/Th17 plasticity.

    Directory of Open Access Journals (Sweden)

    Patricia López

    Full Text Available In this work we analyzed the immune activation properties of different Bifidobacterium strains in order to establish their ability as inductors of specific effector (Th or regulatory (Treg responses. First, we determined the cytokine pattern induced by 21 Bifidobacterium strains in peripheral blood mononuclear cells (PBMCs. Results showed that four Bifidobacterium bifidum strains showed the highest production of IL-17 as well as a poor secretion of IFNγ and TNFα, suggesting a Th17 profile whereas other Bifidobacterium strains exhibited a Th1-suggestive profile. Given the key role of Th17 subsets in mucosal defence, strains suggestive of Th17 responses and the putative Th1 Bifidobacterium breve BM12/11 were selected to stimulate dendritic cells (DC to further determine their capability to induce the differentiation of naïve CD4(+ lymphocytes toward different Th or Treg cells. All selected strains were able to induce phenotypic DC maturation, but showed differences in cytokine stimulation, DC treated with the putative Th17 strains displaying high IL-1β/IL-12 and low IL-12/IL-10 index, whereas BM12/11-DC exhibited the highest IL-12/IL-10 ratio. Differentiation of naïve lymphocytes confirmed Th1 polarization by BM12/11. Unexpectedly, any B. bifidum strain showed significant capability for Th17 generation, and they were able to generate functional Treg, thus suggesting differences between in vivo and vitro responses. In fact, activation of memory lymphocytes present in PBMCS with these bacteria, point out the presence in vivo of specific Th17 cells, supporting the plasticity of Treg/Th17 populations and the key role of commensal bacteria in mucosal tolerance and T cell reprogramming when needed.

  17. Helios expression and Foxp3 TSDR methylation of IFNy+ and IFNy- Treg from kidney transplant recipients with good long-term graft function.

    Directory of Open Access Journals (Sweden)

    Karina Trojan

    Full Text Available There is circumstantial evidence that IFNy+ Treg might have clinical relevance in transplantation. IFNy+ Treg express IFNy receptors and are induced by IFNy. In the present study we investigated in kidney transplant recipients with good long-term stable graft function the absolute cell counts of IFNy+ Treg subsets and whether their expression of Foxp3 is stable or transient.Helios expression determined by eight-color-fluorescence flow cytometry and methylation status of the Foxp3 Treg specific demethylation region (TSDR served as indicators for stability of Foxp3 expression. Methylation status was investigated in enriched IFNy+ and IFNy- Treg preparations originating from peripheral blood using high resolution melt analysis. A total of 136 transplant recipients and 52 healthy controls were studied.Proportions of IFNy+ Treg were similar in patients and healthy controls (0.05% and 0.04% of all CD4+ lymphocytes; p = n.s.. Patients also had similar absolute counts of IFNy producing Helios+ and Helios- Treg (p = n.s.. Most of the IFNy+ and IFNy- Treg in transplant recipients had a methylated Foxp3 TSDR, however, there was a sizeable proportion of IFNy+ and IFNy- Treg with demethylated Foxp3 TSDR. Male and female patients showed more frequently methylated IFNy+ and IFNy- Treg than male and female controls (all p<0.05.Kidney transplant recipients with good long-term stable graft function have similar levels of IFNy+ Treg as healthy controls. IFNy+ and IFNy- Treg subsets in patients consist of cells with stable and cells with transient Foxp3 expression; however, patients showed more frequently methylated IFNy+ and IFNy- Treg than controls. The data show increased levels of Treg subsets with stable as well as transient Foxp3 expression in patients with stable allograft acceptance compared to healthy controls.

  18. β-cell-specific IL-2 therapy increases islet Foxp3+Treg and suppresses type 1 diabetes in NOD mice.

    Science.gov (United States)

    Johnson, Mark C; Garland, Alaina L; Nicolson, Sarah C; Li, Chengwen; Samulski, R Jude; Wang, Bo; Tisch, Roland

    2013-11-01

    Interleukin-2 (IL-2) is a critical cytokine for the homeostasis and function of forkhead box p3-expressing regulatory T cells (Foxp3(+)Tregs). Dysregulation of the IL-2-IL-2 receptor axis is associated with aberrant Foxp3(+)Tregs and T cell-mediated autoimmune diseases such as type 1 diabetes. Treatment with recombinant IL-2 has been reported to enhance Foxp3(+)Tregs and suppress different models of autoimmunity. However, efficacy of IL-2 therapy is dependent on achieving sufficient levels of IL-2 to boost tissue-resident Foxp3(+)Tregs while avoiding the potential toxic effects of systemic IL-2. With this in mind, adeno-associated virus (AAV) vector gene delivery was used to localize IL-2 expression to the islets of NOD mice. Injection of a double-stranded AAV vector encoding IL-2 driven by a mouse insulin promoter (dsAAVmIP-IL2) increased Foxp3(+)Tregs in the islets but not the draining pancreatic lymph nodes. Islet Foxp3(+)Tregs in dsAAVmIP-IL2-treated NOD mice exhibited enhanced fitness marked by increased expression of Bcl-2, proliferation, and suppressor function. In contrast, ectopic IL-2 had no significant effect on conventional islet-infiltrating effector T cells. Notably, β-cell-specific IL-2 expression suppressed late preclinical type 1 diabetes in NOD mice. Collectively, these findings demonstrate that β-cell-specific IL-2 expands an islet-resident Foxp3(+)Tregs pool that effectively suppresses ongoing type 1 diabetes long term.

  19. Effect of EBI3 on radiation-induced immunosuppression of cervical cancer HeLa cells by regulating Treg cells through PD-1/PD-L1 pathway.

    Science.gov (United States)

    Zhang, Song-An; Niyazi, Hu-Er-Xi-Dan; Hong, Wen; Tuluwengjiang, Gu-Li-Xian; Zhang, Lei; Zhang, Yang; Su, Wei-Peng; Bao, Yong-Xing

    2017-03-01

    This study aimed to investigate the effect of EBI3 on radiation-induced immunosuppression of cervical cancer HeLa cells by regulating Treg cells through PD-1/PD-L1 signaling pathway. A total of 43 adult female Wistar rats were selected and injected with HeLa cells in the caudal vein to construct a rat model of cervical cancer. All model rats were randomly divided into the radiotherapy group ( n = 31) and the control group ( n = 12). The immunophenotype of Treg cells was detected by the flow cytometry. The protein expressions of EBI3, PD-1, and PD-L1 in cervical cancer tissues were tested by the streptavidin-peroxidase method. HeLa cells in the logarithmic growth phase were divided into four groups: the blank, the negative control group, the EBI3 mimics group, and the EBI3 inhibitors group. Western blotting was used to detect PD-1 and PD-L1 protein expressions. MTT assay was performed to measure the proliferation of Treg cells. Flow cytometry was used to detect cell cycle and apoptosis, and CD4 + /CD8 + T cell ratio in each group. Compared with before and 1 week after radiotherapy, the percentages of CD4 + T cells and CD8 + T cells were significantly decreased in the radiotherapy group at 1 month after radiotherapy. Furthermore, down-regulation of EBI3 and up-regulation of PD-1 and PD-L1 were observed in cervical cancer tissues at 1 month after radiotherapy. In comparison to the blank and negative control groups, increased expression of EBI3 and decreased expressions of PD-1 and PD-L1 were found in the EBI3 mimics group. However, the EBI3 inhibitors group had a lower expression of EBI3 and higher expressions of PD-1 and PD-L1 than those in the blank and negative control groups. The EBI3 mimics group showed an increase in the optical density value (0.43 ± 0.05), while a decrease in the optical density value (0.31 ± 0.02) was found in the EBI3 inhibitors group. Moreover, compared with the blank and negative control groups, the apoptosis rates

  20. The Balance of Th1/Th2 and LAP+Tregs/Th17 Cells Is Crucial for Graft Survival in Allogeneic Corneal Transplantation

    Directory of Open Access Journals (Sweden)

    Shang Li

    2018-01-01

    Full Text Available Purpose. CD4+LAP+ T cells are newly discovered regulatory T cells (Tregs. The aim of this study is to investigate the balance of Th1/Th2 and LAP+Tregs/Th17 in mice after allogeneic corneal transplantation. Methods. A total of 65 mice received orthotopic penetrating transplantation. According to the survival scores of the grafts, the mice were divided into the rejection group and the survival group 3 weeks after transplantation. Th1, Th2, Th17, and regulatory T cells in the ipsilateral drainage lymph nodes and spleens were measured with flow cytometry. The related cytokines in aqueous humor were also analyzed. Results. The frequencies of Foxp3+Tregs, GARP+Tregs, and LAP+Tregs in the survival group were significantly higher than those in the rejection group. And the expression trend of CD4+LAP+ T cells and CD4+GARP+ T cells was consistent. The level of IFN-γ, TNF, IL-6, and IL-17A markedly increased in aqueous humor during corneal allograft rejection. The ratio of Th1/Th2 and Th17/LAP+Tregs significantly increased in the rejection group at the 3rd week after corneal transplantation. Conclusion. LAP+Tregs might be regarded as substitute for Foxp3+Tregs. The balance of Th1/Th2 and LAP+Tregs/Th17 is crucial for corneal allograft survival.

  1. Changes of Treg and Th17 cells balance in the development of acute and chronic hepatitis B virus infection

    Directory of Open Access Journals (Sweden)

    Xue-Song Liang

    2012-05-01

    Full Text Available Abstract Background Many studies suggest that in chronic hepatitis B virus (HBV infection regulate T (Treg cells and interlukin-17-producing T help cells (Th17 are mutually antagonistic in the immune response. This study is aimed to reveal the cell differentiation environment and the significance of Treg and Th17 balance in the development of acute and chronic HBV infection. Methods Ten patients with acute HBV infection (AHB and forty-eight patients with chronic HBV infection, including 12 asymptomatic HBV carriers (HBV carriers, 18 chronic hepatitis B patients (CHB and 18 acute-on-chronic HBV-related liver failure (ACHBLF were enrolled. Treg and Th17 cells differentiation related cytokine levels were detected by using ELISA. Flow cytometry was employed to count the Treg and Th17 frequency in peripheral blood. Results Compared to health controls both AHB and ACHBLF patients favoured Th17 cell differentiation, accompanied by a higher proportion of peripheral Th17 cells (P  Conclusions Th17 cells are involved in acute and chronic HBV infection, especially in AHB and ACHBLF. CHB and ACHBLF patients manifested obvious Treg/Th17 ratio imbalance, which might be linked to disease progression and the continuous HBV infection.

  2. CBirTox is a selective antigen-specific agonist of the Treg-IgA-microbiota homeostatic pathway.

    Directory of Open Access Journals (Sweden)

    Katie L Alexander

    Full Text Available Cultivating an environment of mutualism between host cells and the microbiota is vital, and dysregulation of this relationship is associated with multiple immune disorders including metabolic and skin diseases, asthma, allergy, and Inflammatory Bowel Disease (IBD. One prominent mechanism for maintaining homeostasis is the protective regulatory T cell (Treg- Immunoglobulin A (IgA pathway toward microbiota antigens, in which Tregs maintain homeostasis and provide critical survival factors to IgA+ B cells. In order to amplify the Treg-IgA pathway, we have generated a fusion protein, CBirTox, comprised of a portion of the carboxy terminus of CBir1, a microbiota flagellin, genetically coupled to Cholera Toxin B subunit (CTB via the A2 linker of CT. Both dendritic cells (DCs and B cells pulsed with CBirTox selectively induced functional CD4+Foxp3+ Tregs in vitro, and CBirTox augmented CD4+Foxp3+ cell numbers in vivo. The induced Foxp3 expression was independent of retinoic acid (RA signaling but was inhibited by neutralization of TGF-β. CBirTox treatment of B cells downregulated mammalian target of rapamycin (mTOR signaling. Furthermore, CBirTox-pulsed DCs induced substantial production of IgA from naïve B cells. Collectively these data demonstrate that CBirTox represents a novel approach to bolstering the Treg-IgA pathway at the host-microbiota interface.

  3. Increased frequency of CD8+ and CD4+ regulatory T cells in chronic lymphocytic leukemia: association with disease progression.

    Science.gov (United States)

    Jadidi-Niaragh, Farhad; Yousefi, Mehdi; Memarian, Ali; Hojjat-Farsangi, Mohammad; Khoshnoodi, Jalal; Razavi, Seyed Mohsen; Jeddi-Tehrani, Mahmood; Shokri, Fazel

    2013-02-01

    Little is known regarding the immunobiology of regulatory T (Treg) cells in hematopoietic malignancies, particularly in chronic lymphocytic leukemia (CLL). In the present study, we showed that the frequencies of CD8(+) and CD4(+) Treg cells were significantly increased in progressive as compared with indolent CLL patients and normal subjects. Enriched CD4(+) Treg cells induced a similar level of inhibition in polyclonally activated B cells and effector T cells from CLL patients and normal subjects. Our results suggest that the increase in circulating Treg cells may result in downregulation of tumor-specific immune response, leading to tumor expansion and disease progression.

  4. Th17/Treg immunoregulation and implications in treatment of sulfur mustard gas-induced lung diseases.

    Science.gov (United States)

    Iman, Maryam; Rezaei, Ramazan; Azimzadeh Jamalkandi, Sadegh; Shariati, Parvin; Kheradmand, Farrah; Salimian, Jafar

    2017-12-01

    Sulfur mustard (SM) is an extremely toxic gas used in chemical warfare to cause massive lung injury and death. Victims exposed to SM gas acutely present with inhalational lung injury, but among those who survive, some develop obstructive airway diseases referred to as SM-lung syndrome. Pathophysiologically, SM-lung shares many characteristics with smoking-induced chronic obstructive pulmonary disease (COPD), including airway remodeling, goblet cell metaplasia, and obstructive ventilation defect. Some of the hallmarks of COPD pathogenesis, which include dysregulated lung inflammation, neutrophilia, recruitment of interleukin 17A (IL -17A) expressing CD4 + T cells (Th17), and the paucity of lung regulatory T cells (Tregs), have also been described in SM-lung. Areas covered: A literature search was performed using the MEDLINE, EMBASE, and Web of Science databases inclusive of all literature prior to and including May 2017. Expert commentary: Here we review some of the recent findings that suggest a role for Th17 cell-mediated inflammatory changes associated with pulmonary complications in SM-lung and suggest new therapeutic approaches that could potentially alter disease progression with immune modulating biologics that can restore the lung Th17/Treg balance.

  5. Kaempferol enhances the suppressive function of Treg cells by inhibiting FOXP3 phosphorylation.

    Science.gov (United States)

    Lin, Fang; Luo, Xuerui; Tsun, Andy; Li, Zhiyuan; Li, Dan; Li, Bin

    2015-10-01

    Kaempferol is a natural flavonoid found in many vegetables and fruits. Epidemiologic studies have described that Kaempferol intake could reduce risk of cancer, especially lung, gastric, pancreatic and ovarian cancers. Recent studies have shown that Kaempferol could also be beneficial to the body to defend against inflammation, and infection by bacteria and viruses; however, the molecular mechanism of its immunoregulatory function remains largely unknown. Through screening a small molecule library of traditional Chinese medicine (TCM), we identified that Kaempferol could enhance the suppressive function of regulatory T cells (Tregs). Kaempferol was found to increase FOXP3 expression level in Treg cells and prevent pathological symptoms of collagen-induced arthritis in a rat animal model. Kaempferol could also reduce PIM1-mediated FOXP3 phosphorylation at S422. Our study reveals a molecular mechanism that underlies the anti-inflammatory action of Kaempferol for the prevention and treatment of inflammatory diseases such as rheumatoid arthritis, systemic lupus erythematosus, and ankylosing spondylitis. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Change of Peripheral Blood Treg/Thl7 in Cognitive Impairment with Chronic Renal Failure Patients

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    Jie Wang

    2018-01-01

    Full Text Available Background/Aims: To investigate the changes in peripheral blood Treg/Th17 cell balance and its significance in patients with chronic renal failure (CRF and cognitive impairment. Methods: A total of 71 patients with CRF were enrolled as a study group. The patients were divided into a cognitive impairment group and a normal cognitive function group according to the Mini-Mental State Examination (MMSE. Peripheral blood Treg and Th17 cells were analyzed by flow cytometry and their relevant cytokines (IL-17, IL-10 and TGF-β and other biochemical indicators, including C-reactive protein (CRP and IL-6, were determined by ELISA. Results: Thepatients with both CRF and cognitive impairment were older than the cognitive normal groups. Peripheral blood Treg cells by Flow cytometry (the CRF cognitive impairment group 5.57±1.3%, CRF group with normal cognitive function 7.5 ± 0.9% and normal control group 9.7 ± 1.7%,P<0.05 and its related cytokines (IL-10 and TGF-β by ELISA detection were lower in the group with cognitive impairment than in the group without cognitive impairment ( IL-10, 7.4±4.2 pg/mL, 13.8±3.9 pg/mL, 18.3±3.2 pg/mL; TGF-β 335.6±175.3 pg/mL, 512.7 ± 114.6 pg/mL, 953.8±373.4 pg/mL P < 0.05, respectively.However, Th17 cell numbers (the CRF cognitive impairment group 3.3 ± 0.7%, CRF group with normal cognitive function2.2 ± 0.5% and normal control group 1.5 ± 0.3%,and cytokine levels (IL-17, IL-6 and CRP were higher in the group with cognitive impairment IL-6 (21.3 ± 5.1 pg/mL, IL-17 (18.5 ± 4.2 pg/mL and CRP (20.3 ± 5.9 mg/L in the CRF group with cognitive impairment when compared with the CRF group and normal cognitive function (12.2 ± 4.5 pg/mL, 12.1 ± 3.7 pg/mL and 13.5 ± 4.6 mg/L, respectively or the normal control group (9.2 ± 5.8 pg/mL, 7.4 ± 2.6 pg/mL and 3.2 ± 1.3 mg/L, respectively, P<0.05. The frequencies of Treg in patients with CRF were positively correlated with the MMSE scores ((r = 0.518, P < 0.05, but the

  7. Change of Peripheral Blood Treg/Thl7 in Cognitive Impairment with Chronic Renal Failure Patients.

    Science.gov (United States)

    Wang, Jie; Li, Xue-Bin; Huang, Peng; Huang, Mei-Ying; Gu, Xian-Jun

    2018-01-01

    To investigate the changes in peripheral blood Treg/Th17 cell balance and its significance in patients with chronic renal failure (CRF) and cognitive impairment. A total of 71 patients with CRF were enrolled as a study group. The patients were divided into a cognitive impairment group and a normal cognitive function group according to the Mini-Mental State Examination (MMSE). Peripheral blood Treg and Th17 cells were analyzed by flow cytometry and their relevant cytokines (IL-17, IL-10 and TGF-β) and other biochemical indicators, including C-reactive protein (CRP) and IL-6, were determined by ELISA. Thepatients with both CRF and cognitive impairment were older than the cognitive normal groups. Peripheral blood Treg cells by Flow cytometry (the CRF cognitive impairment group 5.57±1.3%, CRF group with normal cognitive function 7.5 ± 0.9% and normal control group 9.7 ± 1.7%,Pcognitive impairment than in the group without cognitive impairment ( IL-10, 7.4±4.2 pg/mL, 13.8±3.9 pg/mL, 18.3±3.2 pg/mL; TGF-β 335.6±175.3 pg/mL, 512.7 ± 114.6 pg/mL, 953.8±373.4 pg/mL P cognitive impairment group 3.3 ± 0.7%, CRF group with normal cognitive function2.2 ± 0.5% and normal control group 1.5 ± 0.3%),and cytokine levels (IL-17, IL-6 and CRP) were higher in the group with cognitive impairment IL-6 (21.3 ± 5.1 pg/mL), IL-17 (18.5 ± 4.2 pg/mL) and CRP (20.3 ± 5.9 mg/L) in the CRF group with cognitive impairment when compared with the CRF group and normal cognitive function (12.2 ± 4.5 pg/mL, 12.1 ± 3.7 pg/mL and 13.5 ± 4.6 mg/L, respectively) or the normal control group (9.2 ± 5.8 pg/mL, 7.4 ± 2.6 pg/mL and 3.2 ± 1.3 mg/L, respectively, Pcognitive impairment in patients with CRF. © 2018 The Author(s). Published by S. Karger AG, Basel.

  8. Ctla-4 modulates the differentiation of inducible Foxp3+ Treg cells but IL-10 mediates their function in experimental autoimmune encephalomyelitis.

    Directory of Open Access Journals (Sweden)

    Johan Verhagen

    Full Text Available In vitro induced Foxp3+ T regulatory (iTreg cells form a novel and promising target for therapeutic tolerance induction. However, the potential of these cells as a target for the treatment of various immune diseases, as well as the factors involved in their development and function, remain debated. Here, we demonstrate in a myelin basic protein (MBP-specific murine model of CNS autoimmune disease that adoptive transfer of antigen-specific iTreg cells ameliorates disease progression. Moreover, we show that the co-stimulatory molecule CTLA-4 mediates in vitro differentiation of iTreg cells. Finally, we demonstrate that the secreted, immunosuppressive cytokine IL-10 controls the ability of antigen-specific iTreg cells to suppress autoimmune disease. Overall, we conclude that antigen-specific iTreg cells, which depend on various immune regulatory molecules for their differentiation and function, represent a major target for effective immunotherapy of autoimmune disease.

  9. Reconstitution of Th17, Tc17 and Treg cells after paediatric haematopoietic stem cell transplantation

    DEFF Research Database (Denmark)

    Kielsen, Katrine; Ryder, Lars P; Lennox-Hvenekilde, David

    2018-01-01

    behind these associations have not been investigated previously. We hypothesized that increased levels of IL-7 post-transplant alters the balance between immune-regulatory T cell subsets during the post-transplant lymphocyte recovery towards a more pro-inflammatory profile. We quantified Th17 cells, Tc17.......025). The plasma level of IL-7 at day +90 correlated inversely with Th17 cell counts (rs=-0.65, P=0.0002) and the proportion of Tc17 cells (rs=0.64, P=0.0005) at day +90, but not with Tregs. Furthermore, high IL-7 levels at day +7 were predictive of a less naïve T-cell phenotype at day +90. These findings add...

  10. mTOR Inhibition Attenuates Dextran Sulfate Sodium-Induced Colitis by Suppressing T Cell Proliferation and Balancing TH1/TH17/Treg Profile.

    Directory of Open Access Journals (Sweden)

    Shurong Hu

    Full Text Available It has been established that mammalian target of Rapamycin (mTOR inhibitors have anti-inflammatory effects in models of experimental colitis. However, the underlying mechanism is largely unknown. In this research, we investigate the anti-inflammatory effects of AZD8055, a potent mTOR inhibitor, on T cell response in dextran sulfate sodium (DSS-induced colitis in mice, a commonly used animal model of inflammatory bowel diseases (IBD. Severity of colitis is evaluated by changing of body weight, bloody stool, fecal consistency, histology evaluation and cytokine expression. We find that AZD8055 treatment attenuates DSS-induced body weight loss, colon length shortening and pathological damage of the colon. And AZD8055 treatment decreases colonic expression of genes encoding the pro-inflammatory cytokines interferon-γ, interleukin (IL-17A, IL-1β,IL-6 and tumor necrosis factor(TNF-a and increases colonic expression of anti-inflammatory cytokines IL-10. We show that AZD8055 treatment decreases the percentages of CD4+ T cells and CD8+ T cells in spleen, lymph nodes and peripheral blood of mice. We also find that AZD8055 treatment significantly reduces the number of T helper 1(TH1 cells and TH17 cells and increases regulatory T (Treg cells in the lamina propria and mesenteric lymph nodes. Furthermore, we demonstrates that AZD8055 suppresses the proliferation of CD4+ and CD8+ T cells and the differentiation of TH1/TH17 cells and expands Treg cells in vitro. The results suggest that, in experimental colitis, AZD8055 exerts anti-inflammatory effect by regulating T helper cell polarization and proliferation.

  11. Effect of statins as modulators of CD39+ tregs in patients with rheumatoid arthritis who were unsuccessfully treated with methotrexate

    Directory of Open Access Journals (Sweden)

    Mohammed H Abu-Zaid

    2018-01-01

    Conclusion Combination therapy with AV and ETA provides an added immunomodulatory benefit through enhancement of the immune suppression mediated by CD39+ Treg cells. Therefore, statins can be used safely with antitumor necrosis factor drugs to control disease activity and atherosclerotic changes in patients with RA, who are treated unsuccessfully with MTX.

  12. Regulating the Balance of Th17/Treg via Electroacupuncture and Moxibustion: An Ulcerative Colitis Mice Model Based Study

    Directory of Open Access Journals (Sweden)

    Jungang Sun

    2017-01-01

    Full Text Available Aim. To investigate the relationship between the effects of electroacupuncture/moxibustion and the balance of Th17/Treg in treating ulcerative colitis (UC and to preliminary compare the effects of the above two methods. Methods. DSS-induced UC mice were treated by electroacupuncture and moxibustion. Disease activity index (DAI was scored; intestinal pathological structure and ultrastructure were observed. The levels of IL-2, IL-6, IL-10, IL-17A, IL-17F, and TGF-β in plasma were measured by ELISA. The percentages of Treg and Th17 in spleen lymphocytes were analyzed by flow cytometry. Also, the expressions of TLR2, TLR4, RORγt, and FOXP3 in the distal colon were detected by immunohistochemistry or western blot. Results. Both electroacupuncture and moxibustion can relieve UC. These effects are further supported by ELISA results. In addition, the ratio of Treg and Th17 in spleen lymphocytes and the expression of TLR2 and TLR4 are significantly improved. Also, the expression of RORγt and FOXP3 in distal colon were improved. Besides, the effect of moxibustion is better than that of electroacupuncture on TLR2, TLR4, and FOXP3 expression (P<0.05. Conclusion. Both electroacupuncture and moxibustion may ameliorate UC by regulating the balance of Th17/Treg. Whether moxibustion has better efficacy than electroacupuncture needs further study.

  13. Alterations in the adenosine metabolism and CD39/CD73 adenosinergic machinery cause loss of Treg cell function and autoimmunity in ADA-deficient SCID

    Science.gov (United States)

    Sauer, Aisha V.; Brigida, Immacolata; Carriglio, Nicola; Jofra Hernandez, Raisa; Scaramuzza, Samantha; Clavenna, Daniela; Sanvito, Francesca; Poliani, Pietro L.; Gagliani, Nicola; Carlucci, Filippo; Tabucchi, Antonella; Roncarolo, Maria Grazia; Traggiai, Elisabetta; Villa, Anna

    2012-01-01

    Adenosine acts as anti-inflammatory mediator on the immune system and has been described in regulatory T cell (Treg)–mediated suppression. In the absence of adenosine deaminase (ADA), adenosine and other purine metabolites accumulate, leading to severe immunodeficiency with recurrent infections (ADA-SCID). Particularly ADA-deficient patients with late-onset forms and after enzyme replacement therapy (PEG-ADA) are known to manifest immune dysregulation. Herein we provide evidence that alterations in the purine metabolism interfere with Treg function, thereby contributing to autoimmune manifestations in ADA deficiency. Tregs isolated from PEG-ADA–treated patients are reduced in number and show decreased suppressive activity, whereas they are corrected after gene therapy. Untreated murine ADA−/− Tregs show alterations in the plasma membrane CD39/CD73 ectonucleotidase machinery and limited suppressive activity via extracellular adenosine. PEG-ADA–treated mice developed multiple autoantibodies and hypothyroidism in contrast to mice treated with bone marrow transplantation or gene therapy. Tregs isolated from PEG-ADA–treated mice lacked suppressive activity, suggesting that this treatment interferes with Treg functionality. The alterations in the CD39/CD73 adenosinergic machinery and loss of function in ADA-deficient Tregs provide new insights into a predisposition to autoimmunity and the underlying mechanisms causing defective peripheral tolerance in ADA-SCID. Trials were registered at www.clinicaltrials.gov as NCT00598481/NCT00599781. PMID:22184407

  14. Neuronal IFN-beta-induced PI3K/Akt-FoxA1 signalling is essential for generation of FoxA1(+)Treg cells

    DEFF Research Database (Denmark)

    Liu, Yawei; Marin, Andrea; Ejlerskov, Patrick

    2017-01-01

    Neurons reprogramme encephalitogenic T cells (Tenc) to regulatory T cells (Tregs), either FoxP3(+)Tregs or FoxA1(+)Tregs. We reported previously that neuronal ability to generate FoxA1(+)Tregs was central to preventing neuroinflammation in experimental autoimmune encephalomyelitis (EAE). Mice...... lacking interferon (IFN)-β were defective in generating FoxA1(+)Tregs in the brain. Here we show that lack of neuronal IFNβ signalling is associated with the absence of programme death ligand-1 (PDL1), which prevents their ability to reprogramme Tenc cells to FoxA1(+)Tregs. Passive transfer-EAE via IFNβ......-competent Tenc cells to mice lacking IFNβ and active induced-EAE in mice lacking its receptor, IFNAR, in the brain (Nes(Cre):Ifnar(fl/fl)) result in defective FoxA1(+)Tregs generation and aggravated neuroinflammation. IFNβ activates neuronal PI3K/Akt signalling and Akt binds to transcription factor FoxA1...

  15. IFNy+ and IFNy- Treg subsets with stable and unstable Foxp3 expression in kidney transplant recipients with good long-term graft function.

    Science.gov (United States)

    Trojan, Karina; Unterrainer, Christian; Aly, Mostafa; Zhu, Li; Weimer, Rolf; Bulut, Nuray; Morath, Christian; Opelz, Gerhard; Daniel, Volker

    2016-10-29

    Treg are a heterogenous cell population. In the present study we attempted to identify Treg subsets that might contribute to stable and good long-term graft function. Lymphocyte and Treg subsets were studied in 136 kidney transplant recipients with good long-term graft function and in 52 healthy control individuals using eight-color-fluorescence flow cytometry. Foxp3 TSDR methylation status was investigated in enriched IFNy+ and IFNy- Treg preparations using high resolution melt analysis. Compared with healthy controls, patients showed strong associations of IFNy secreting Helios+ and Helios- Treg with Treg that co-expressed perforin and/or CTLA4 (CD152; pterm graft function possess IFNy+ and IFNy- Treg with stable and unstable Foxp3 expression in the blood. They co-express CD28, HLADR, CTLA4, CXCR3, Lselectin, TGFβ, perforin and FasL and might contribute to the establishment and maintenance of good long-term graft function. Copyright © 2016. Published by Elsevier B.V.

  16. Alterations in the adenosine metabolism and CD39/CD73 adenosinergic machinery cause loss of Treg cell function and autoimmunity in ADA-deficient SCID.

    Science.gov (United States)

    Sauer, Aisha V; Brigida, Immacolata; Carriglio, Nicola; Hernandez, Raisa Jofra; Scaramuzza, Samantha; Clavenna, Daniela; Sanvito, Francesca; Poliani, Pietro L; Gagliani, Nicola; Carlucci, Filippo; Tabucchi, Antonella; Roncarolo, Maria Grazia; Traggiai, Elisabetta; Villa, Anna; Aiuti, Alessandro

    2012-02-09

    Adenosine acts as anti-inflammatory mediator on the immune system and has been described in regulatory T cell (Treg)-mediated suppression. In the absence of adenosine deaminase (ADA), adenosine and other purine metabolites accumulate, leading to severe immunodeficiency with recurrent infections (ADA-SCID). Particularly ADA-deficient patients with late-onset forms and after enzyme replacement therapy (PEG-ADA) are known to manifest immune dysregulation. Herein we provide evidence that alterations in the purine metabolism interfere with Treg function, thereby contributing to autoimmune manifestations in ADA deficiency. Tregs isolated from PEG-ADA-treated patients are reduced in number and show decreased suppressive activity, whereas they are corrected after gene therapy. Untreated murine ADA(-/-) Tregs show alterations in the plasma membrane CD39/CD73 ectonucleotidase machinery and limited suppressive activity via extracellular adenosine. PEG-ADA-treated mice developed multiple autoantibodies and hypothyroidism in contrast to mice treated with bone marrow transplantation or gene therapy. Tregs isolated from PEG-ADA-treated mice lacked suppressive activity, suggesting that this treatment interferes with Treg functionality. The alterations in the CD39/CD73 adenosinergic machinery and loss of function in ADA-deficient Tregs provide new insights into a predisposition to autoimmunity and the underlying mechanisms causing defective peripheral tolerance in ADA-SCID.

  17. CD8+CD122+CD49dlow regulatory T cells maintain T-cell homeostasis by killing activated T cells via Fas/FasL-mediated cytotoxicity.

    Science.gov (United States)

    Akane, Kazuyuki; Kojima, Seiji; Mak, Tak W; Shiku, Hiroshi; Suzuki, Haruhiko

    2016-03-01

    The Fas/FasL (CD95/CD178) system is required for immune regulation; however, it is unclear in which cells, when, and where Fas/FasL molecules act in the immune system. We found that CD8(+)CD122(+) cells, which are mostly composed of memory T cells in comparison with naïve cells in the CD8(+)CD122(-) population, were previously shown to include cells with regulatory activity and could be separated into CD49d(low) cells and CD49d(high) cells. We established in vitro and in vivo experimental systems to evaluate the regulatory activity of CD122(+) cells. Regulatory activity was observed in CD8(+)CD122(+)CD49d(low) but not in CD8(+)CD122(+)CD49d(high) cells, indicating that the regulatory cells in the CD8(+)CD122(+) population could be narrowed down to CD49d(low) cells. CD8(+)CD122(-) cells taken from lymphoproliferation (lpr) mice were resistant to regulation by normal CD122(+) Tregs. CD122(+) Tregs taken from generalized lymphoproliferative disease (gld) mice did not regulate wild-type CD8(+)CD122(-) cells, indicating that the regulation by CD122(+) Tregs is Fas/FasL-dependent. CD122(+) Tregs taken from IL-10-deficient mice could regulate CD8(+)CD122(-) cells as equally as wild-type CD122(+) Tregs both in vitro and in vivo. MHC class I-missing T cells were not regulated by CD122(+) Tregs in vitro. CD122(+) Tregs also regulated CD4(+) cells in a Fas/FasL-dependent manner in vitro. These results suggest an essential role of Fas/FasL as a terminal effector of the CD122(+) Tregs that kill activated T cells to maintain immune homeostasis.

  18. Analysis of miR-146a and miR-142-3p as Potential Markers of Freshly Isolated or In Vitro-Expanded Human Treg cells

    DEFF Research Database (Denmark)

    Holmstrøm, K; Pedersen, A E; Gad, M

    2017-01-01

    Regulatory CD4(+) T cells (Tregs) are pivotal for prevention of autoimmunity. The use of Tregs is therefore of increasing interest in in vitro drug screening assays as well as for a cytotherapy per se against autoimmune disorders. For both purposes, in vitro expansion of peripheral blood Tregs...... in the same markers in activated tTregs as opposed to naïve tTregs. In vitro-expanded Tregs could be identified based on FOXP3 expression, but with loss of a discriminate profile for miRNA candidates and a decline in FOXP3 when activated tTregs were expanded. Our data demonstrate miR-146a and 142-3p...... and cytotherapy as FOXP3 is pivotal for suppressive function....

  19. TH17, TH22 and Treg cells are enriched in the healthy human cecum.

    Directory of Open Access Journals (Sweden)

    Martin J Wolff

    Full Text Available There is increasing evidence that dysregulation of CD4(+ T cell populations leads to intestinal inflammation, but the regional distribution of these populations throughout the intestinal tract in healthy individuals remains unclear. Here, we show that T(H17, T(H22 and T(Reg cells are enriched in the healthy human cecum compared to the terminal ileum and sigmoid colon, whereas T(H1 and T(H2 cells do not significantly vary by location. Transcriptional profiling analysis of paired pinch biopsies from different regions of the intestine identified significant differences in the metabolic state of the terminal ileum, cecum, and sigmoid colon. An increased proportion of T(H17 cells was positively associated with expression of resistin (RETN and negatively associated with expression of trefoil factor 1 (TFF1. These results suggest that CD4(+ T helper cells that are important in maintaining mucosal barrier function may be enriched in the cecum as a result of metabolic differences of the surrounding microenvironment.

  20. Helicobacter pylori neutrophil-activating protein: A potential Treg modulator suppressing allergic asthma?

    Directory of Open Access Journals (Sweden)

    Anjna eSehrawat

    2015-06-01

    Full Text Available The ultimate aim of immunology is to kill the pathogen without being harmful to the host. But what if eliminating the pathogen in itself is discomforting for the host? One such emerging case is of Helicobacter pylori. Modern medicine, infantile vaccination and ultra-hygienic conditions have led to progressive disappearance of H. pylori in different parts of the world. However, the adversities caused by H. pylori’s absence are much larger than those caused by its presence. Asthma is rising as an epidemic in last few decades and several reports suggest an inverse-relationship between H. pylori’s persistence and early-life onset asthma. Regulatory T cells play an important role in both the cases. This is further supported by experiments on mouse-models. Hence, need of the hour is to discern the relationship between H. pylori and its host and eliminating its negative impacts without disturbing our indigenous microbiota. To resolve whether H. pylori is a pathogen or an amphibiont is another important side. This review explores the biological basis of H. pylori-induced priming of immune system offering resistance to childhood-onset asthma. HP-NAP-Tregs interaction has been predicted using molecular docking and dynamic simulation.

  1. Oral myeloid cells uptake allergoids coupled to mannan driving Th1/Treg responses upon sublingual delivery in mice.

    Science.gov (United States)

    Soria, I; López-Relaño, J; Viñuela, M; Tudela, J-I; Angelina, A; Benito-Villalvilla, C; Díez-Rivero, C M; Cases, B; Manzano, A I; Fernández-Caldas, E; Casanovas, M; Palomares, O; Subiza, J L

    2018-04-01

    Polymerized allergoids coupled to nonoxidized mannan (PM-allergoids) may represent novel vaccines targeting dendritic cells (DCs). PM-allergoids are better captured by DCs than native allergens and favor Th1/Treg cell responses upon subcutaneous injection. Herein we have studied in mice the in vivo immunogenicity of PM-allergoids administered sublingually in comparison with native allergens. Three immunization protocols (4-8 weeks long) were used in Balb/c mice. Serum antibody levels were tested by ELISA. Cell responses (proliferation, cytokines, and Tregs) were assayed by flow cytometry in spleen and lymph nodes (LNs). Allergen uptake was measured by flow cytometry in myeloid sublingual cells. A quick antibody response and higher IgG2a/IgE ratio were observed with PM-allergoids. Moreover, stronger specific proliferative responses were seen in both submandibular LNs and spleen cells assayed in vitro. This was accompanied by a higher IFNγ/IL-4 ratio with a quick IL-10 production by submandibular LN cells. An increase in CD4 + CD25 high FOXP3 + Treg cells was detected in LNs and spleen of mice treated with PM-allergoids. These allergoids were better captured than native allergens by antigen-presenting (CD45 + MHC-II + ) cells obtained from the sublingual mucosa, including DCs (CD11b + ) and macrophages (CD64 + ). Importantly, all the differential effects induced by PM-allergoids were abolished when using oxidized instead of nonoxidized PM-allergoids. Our results demonstrate for the first time that PM-allergoids administered through the sublingual route promote the generation of Th1 and FOXP3 + Treg cells in a greater extent than native allergens by mechanisms that might well involve their better uptake by oral antigen-presenting cells. © 2018 The Authors. Allergy Published by John Wiley & Sons Ltd.

  2. An endogenous aryl hydrocarbon receptor (AhR) ligand, ITE induces regulatory T cells (Tregs) and ameliorates experimental colitis.

    Science.gov (United States)

    Abron, Jessicca D; Singh, Narendra P; Mishra, Manoj K; Price, Robert L; Nagarkatti, Mitzi; Nagarkatti, Prakash S; Singh, Udai P

    2018-04-19

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that affects millions of people with high morbidity and health-care cost. The precise etiology of IBD is unknown, but clear evidence suggests that intestinal inflammation is caused by an excessive immune response to mucosal antigens. Recent studies have shown that activation of the aryl hydrocarbon receptor (AhR) induces regulatory T cells (Tregs) and suppresses autoimmune diseases. In the current study, we investigated if nontoxic ligand of AhR, 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), can attenuate dextran sodium sulphate (DSS)-induced colitis. Our studies demonstrated that in mice that received ITE treatment, in-vivo colitis pathogenesis, including a decrease in body weight, was significantly reversed along with the systemic and intestinal inflammatory cytokines. ITE increased the expression of Tregs in spleen, mesenteric lymph nodes (MLNs) and colon lamina propria lymphocytes (cLPL) of mice with colitis when compared to controls. This induction of Tregs was reversed by AhR antagonist treatment in-vitro. ITE treatment also increased dendritic cells (DCs; CD11c+) and decreased F4/80+ (macrophage) from the spleen, MLNs and cLPL in mice with colitis. ITE also reversed the systemic and intestinal frequency of CD4+T cells during colitis and suppressed inflammatory cytokines including IFN-γ, TNF-α, IL-17, IL-6 and IL-1 as well as induced IL-10 levels. These findings suggest that ITE attenuates colitis through induction of Tregs and reduction in inflammatory CD4+ T cells and cytokines. Thus, our work demonstrates that the nontoxic endogenous AhR ligand ITE, may serve as a therapeutic modality to treat IBD.

  3. 3-bromopyruvate ameliorate autoimmune arthritis by modulating Th17/Treg cell differentiation and suppressing dendritic cell activation

    OpenAIRE

    Okano, Takaichi; Saegusa, Jun; Nishimura, Keisuke; Takahashi, Soshi; Sendo, Sho; Ueda, Yo; Morinobu, Akio

    2017-01-01

    Recent studies have shown that cellular metabolism plays an important role in regulating immune cell functions. In immune cell differentiation, both interleukin-17-producing T (Th17) cells and dendritic cells (DCs) exhibit increased glycolysis through the upregulation of glycolytic enzymes, such as hexokinase-2 (HK2). Blocking glycolysis with 2-deoxyglucose was recently shown to inhibit Th17 cell differentiation while promoting regulatory T (Treg) cell generation. However, 2-DG inhibits all i...

  4. TGF-β induces the expression of Nedd4 family-interacting protein 1 (Ndfip1) to silence IL-4 production during iTreg cell differentiation

    Science.gov (United States)

    Beal, Allison M.; Ramos-Hernández, Natalia; Riling, Chris R.; Nowelsky, Erin A.; Oliver, Paula M.

    2011-01-01

    Mice deficient for the adaptor Ndfip1 develop inflammation at sites of environmental antigen exposure. We show here that these animals contain fewer inducible regulatory (iTreg) cells. In vitro, Ndfip1-deficient T cells express normal levels of the transcription factor Foxp3 during the first 48 hours of iTreg cell differentiation, however this cannot be sustained. Abortive Foxp3 expression is because Ndfip1–/– cells produce interleukin 4 (IL-4). We demonstrate that Ndfip1 is transiently unregulated during iTreg cell differentiation in a transforming growth factor-β (TGF-β) dependent manner. Once expressed Ndfip1 promotes Itch-mediated degradation of the transcription factor JunB, thus preventing IL-4 production. Based on these data, we propose that TGF-β signaling induces Ndfip1 expression to silence IL-4 production, thus permitting iTreg cell differentiation. PMID:22080920

  5. 3-bromopyruvate ameliorate autoimmune arthritis by modulating Th17/Treg cell differentiation and suppressing dendritic cell activation.

    Science.gov (United States)

    Okano, Takaichi; Saegusa, Jun; Nishimura, Keisuke; Takahashi, Soshi; Sendo, Sho; Ueda, Yo; Morinobu, Akio

    2017-02-10

    Recent studies have shown that cellular metabolism plays an important role in regulating immune cell functions. In immune cell differentiation, both interleukin-17-producing T (Th17) cells and dendritic cells (DCs) exhibit increased glycolysis through the upregulation of glycolytic enzymes, such as hexokinase-2 (HK2). Blocking glycolysis with 2-deoxyglucose was recently shown to inhibit Th17 cell differentiation while promoting regulatory T (Treg) cell generation. However, 2-DG inhibits all isoforms of HK. Thus, it is unclear which isoform has a critical role in Th17 cell differentiation and in rheumatoid arthritis (RA) pathogenesis. Here we demonstrated that 3-bromopyruvate (BrPA), a specific HK2 inhibitor, significantly decreased the arthritis scores and the histological scores in SKG mice, with a significant increase in Treg cells, decrease in Th17 cells, and decrease in activated DCs in the spleen. In vitro, BrPA facilitated the differentiation of Treg cells, suppressed Th17 cells, and inhibited the activation of DCs. These results suggested that BrPA may be a therapeutic target of murine arthritis. Although the role of IL-17 is not clarified in the treatment of RA, targeting cell metabolism to alter the immune cell functions might lead to a new therapeutic strategy for RA.

  6. TLR2/TLR4 activation induces Tregs and suppresses intestinal inflammation caused by Fusobacterium nucleatum in vivo.

    Directory of Open Access Journals (Sweden)

    Yin-Ping Jia

    Full Text Available Toll-like receptors (TLRs 2 and 4 play critical roles in intestinal inflammation caused by Fusobacterium nucleatum (F. nucleatum infection, but the role of TLR2/TLR4 in regulation of proinflammatory cytokines remains unknown. In this study, through microarray analysis and qRT-PCR, we showed that TLR2/TLR4 are involved in the F. nucleatum-induced inflammatory signaling pathway in Caco-2 cells, C57BL/6 mice and human clinical specimens. In TLR2-/- and TLR4-/- mice, F. nucleatum infection resulted in increased colonization of the bacteria and production of the proinflammatory cytokines IL-8, IL-1β and TNF-α. In addition, the ratio of Foxp3+ CD4+ T cells in the total CD4+ T cells in TLR2-/- and TLR4-/- mice was less than that in wild-type mice, and the ratio in hybrid mice was more than that in knockout mice, which suggested that TLR2/TLR4 mediated the number of Tregs. Furthermore, it was observed that inflammatory cytokine levels were reduced in TLR2-/- mice after Treg transfer. Thus, these data indicate that TLR2/TLR4 regulate F. nucleatum-induced inflammatory cytokines through Tregs in vivo.

  7. Tolerogenic Dendritic Cells Generated with Tofacitinib Ameliorate Experimental Autoimmune Encephalomyelitis through Modulation of Th17/Treg Balance

    Directory of Open Access Journals (Sweden)

    Yan Zhou

    2016-01-01

    Full Text Available It is well known that dendritic cells (DCs play a pivotal role in triggering self-specific responses. Conversely, tolerogenic DCs (tolDCs, a specialized subset, induce tolerance and negatively regulate autoreactive responses. Tofacitinib, a Janus kinase inhibitor developed by Pfizer for treatment of rheumatoid arthritis, is probable to be a promising candidate for inducing tolDCs. The aims of this study were to evaluate the effectiveness of tolDCs induced by tofacitinib in a myelin oligodendrocyte glycoprotein- (MOG- specific experimental autoimmune encephalomyelitis (EAE model and to investigate their effects on Th17/Treg balance in the animal model of multiple sclerosis (MS. Our results revealed that tofacitinib-treated DCs maintained a steady semimature phenotype with a low level of proinflammatory cytokines and costimulatory molecules. DCs treated by tofacitinib also induced antigen-specific T cells hyporesponsiveness in a concentration-dependent manner. Upon intravenous injection into EAE mice, MOG pulsed tolDCs significantly dampened disease activity, and adoptive cell therapy (ACT disturbed Th17/Treg balance with a remarkable decrease of Th1/Th17 cells and an increase in regulatory T cells (Tregs. Overall, DCs modified by tofacitinib exhibited a typical tolerogenic phenotype, and the antigen-specific tolDCs may represent a new avenue of research for the development of future clinical treatments for MS.

  8. The beneficial effect of total glucosides of paeony on psoriatic arthritis links to circulating Tregs and Th1 cell function.

    Science.gov (United States)

    Wang, Yi Na; Zhang, Yu; Wang, Yan; Zhu, Ding Xian; Xu, Li Qin; Fang, Hong; Wu, Wei

    2014-03-01

    Total glycosides of peony (TGP) is a natural immuno-modulatory drug extracted from traditional Chinese herb peony. It has been approved by State Food and Drug Administration for the treatment of rheumatoid arthritis. However, data of TGP effect on psoriatic arthritis (PsA) is still scarce. In this study, 19 patients with PsA received 12-week treatment of TGP, and clinical efficacy in joint manifestations was evaluated by DAS28 at weeks 0, 4, 8 and 12. Peripheral percentages of Tregs, Th1, Th2 and NK cells were analyzed, and serum Th1-type cytokines (IL-12, IFN-γ and TNF-α), Th2-type cytokines (IL-4, IL-5 and IL-10) as well as pro-inflammatory factors (IL-2, IL-6 and IL-8) were concomitantly examined. Six patients (32%) exhibited ≥25% decrease of DAS28 (responders). Interestingly, all responders displayed a continuous decrease in Treg and Th1 numbers during TGP treatment, concomitant with significant decreases in Th1-type cytokine levels. Serum IL-6 also showed a significant decline in responders. Non-responders lacked these sequential alterations. Thus, TGP merits further consideration as a promising therapeutic option for PsA. The result indicated that recovery of Tregs and Th1 may serve as prognostic markers to assess responsiveness to TGP treatment in PsA. Copyright © 2013 John Wiley & Sons, Ltd.

  9. Role of PD1/PDL1 pathway, and TH17 and treg cells in maternal tolerance to the fetus

    Directory of Open Access Journals (Sweden)

    Sudipta Tripathi

    2015-02-01

    Full Text Available Tolerance of the fetus by the maternal immune system is regulated through various mechanisms involving the different immune cells, both in the periphery and locally at the feto-maternal interface. The maternal T lymphocytes are aware of the paternal fetal antigens and a state of dynamic T cell homeostasis is maintained in the uterus during gestation, which involves increase in antigen-specific regulatory T cell (Treg proliferation, increase in apoptosis of antigen-specific effector T cells, and inhibition of excessive inflammation post successful implantation to ensure tolerance to the fetus. The Tregs play an important role in the maintenance of tolerance during gestation. Recently, the inflammatory T helper type 17 (Th17 cells are reported to have a role in loss of tolerance to the fetus. The interaction between costimulatory molecule programmed death 1 (PD1 and its ligand PDL1 is known to play a role in regulating both the Tregs and Th17 cells. Here we discuss how the PD1/PDL1 pathway affects these two T cell populations and its role in feto-maternal tolerance.

  10. Influence of budesonide and salbutamol atomization inhalation on Th17/ Treg balance in patients with bronchial asthma and its correlation with airway remodeling

    Directory of Open Access Journals (Sweden)

    Kun-Feng Zhang1

    2017-05-01

    Full Text Available Objective: To study the influence of budesonide and salbutamol atomization inhalation on Th17/Treg balance in patients with bronchial asthma and its correlation with airway remodeling. Methods: A total of 90 patients with bronchial asthma who received systemic treatment in our hospital between July 2013 and April 2016 were divided into control group (n=45 and observation group (n=45 according to random number table. Patients in the control group were treated with salbutamol atomization inhalation alone while those in observation group were treated with budesonide and salbutamol atomization inhalation. The Th17/Treg ratio in peripheral blood as well as serum contents of airway remodeling-related indicators was compared between two groups before and after treatment. The correlation between Th17/Treg balance and airway remodeling in patients with bronchial asthma was detected by Pearson test. Results: Before treatment, the differences in peripheral blood Th17/Treg ratio as well as serum contents of inflammatory mediators, growth factor indexes and collagen metabolism indexes were not statistically significant between two groups of patients. After treatment, peripheral blood Th17/Treg ratio in observation group was lower than that in control group, serum CRP, IL-8, IL-13 and TNF-αcontents in observation group were lower than those in control group, serum PDGF-BB, b-FGF and VEGF contents in observation group were lower than those in control group, and serum HA, PCⅢ and LN contents in observation group were lower than those in control group. The Th17/Treg ratio in patients with bronchial asthma after treatment was positively correlated with the levels of airway remodeling-related indexes. Conclusion: Budesonide combined with salbutamol atomization inhalation can optimize the Th17/Treg balance in patients with bronchial asthma, and Th17/Treg is directly correlated to the degree of airway remodeling.

  11. Human mesenchymal stromal cells enhance the immunomodulatory function of CD8+CD28− regulatory T cells

    Science.gov (United States)

    Liu, Qiuli; Zheng, Haiqing; Chen, Xiaoyong; Peng, Yanwen; Huang, Weijun; Li, Xiaobo; Li, Gang; Xia, Wenjie; Sun, Qiquan; Xiang, Andy Peng

    2015-01-01

    One important aspect of mesenchymal stromal cells (MSCs)-mediated immunomodulation is the recruitment and induction of regulatory T (Treg) cells. However, we do not yet know whether MSCs have similar effects on the other subsets of Treg cells. Herein, we studied the effects of MSCs on CD8+CD28− Treg cells and found that the MSCs could not only increase the proportion of CD8+CD28− T cells, but also enhance CD8+CD28−T cells' ability of hampering naive CD4+ T-cell proliferation and activation, decreasing the production of IFN-γ by activated CD4+ T cells and inducing the apoptosis of activated CD4+ T cells. Mechanistically, the MSCs affected the functions of the CD8+CD28− T cells partially through moderate upregulating the expression of IL-10 and FasL. The MSCs had no distinct effect on the shift from CD8+CD28+ T cells to CD8+CD28− T cells, but did increase the proportion of CD8+CD28− T cells by reducing their rate of apoptosis. In summary, this study shows that MSCs can enhance the regulatory function of CD8+CD28− Treg cells, shedding new light on MSCs-mediated immune regulation. PMID:25482073

  12. Appropriate Development of the Liver Treg Compartment Is Modulated by the Microbiota and Requires TGF-β and MyD88

    Directory of Open Access Journals (Sweden)

    Ann Maria

    2014-01-01

    Full Text Available Neither the early postnatal development of the liver Treg compartment nor the factors that regulate its development has been characterized. We compared the early developmental patterns of Treg cell accumulation in murine liver, thymus, and spleen. A FoxP3EGFP reporter mouse was employed to identify Treg cells. Mononuclear cells were isolated from organs postnatally, stained for CD4, and examined by flow cytometry to enumerate FoxP3+CD4hi cells. To assess roles for TGF-β1, MyD88, and TLR2, gene-specific knockout pups were generated from heterozygous breeders. To test the role of commensal bacteria, pregnant dams were administered antibiotics during gestation and after parturition. The pattern of appearance of Treg cells differed in liver, spleen, and thymus. Notably, at 1-2 weeks, the frequency of CD4hi FoxP3+ T cells in liver exceeded that in spleen by 1.5- to 2-fold. The relative increase in liver Treg frequency was transient and was dependent upon TGF-β1 and MyD88, but not TLR2, and was abrogated by antibiotic treatment. A relative increase in liver Treg frequency occurs approximately 1-2 weeks after parturition that appears to be driven by colonization of the intestine with commensal bacteria and is mediated by a pathway that requires TGF-β1 and MyD88, but not TLR2.

  13. CD4+CD25+ T regulatory cells from FIV+ cats induce a unique anergic profile in CD8+ lymphocyte targets

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    Tompkins Mary B

    2010-11-01

    Full Text Available Abstract Background Using the FIV model, we reported previously that CD4+CD25+ T regulatory (Treg cells from FIV+ cats are constitutively activated and suppress CD4+CD25- and CD8+ T cell immune responses. In an effort to further explore Treg-mediated suppression, we asked whether Treg cells induce anergy through the alteration of production of cyclins, cyclin-dependent kinases and their inhibitors. Results Lymphocytes were obtained from control or FIV+ cats and sorted by FACS into CD4+CD25+ and CD8+ populations. Following co-culture with CD4+CD25+ cells, CD8+ targets were examined by Western blot for changes in cyclins D3, E and A, retinoblastoma (Rb protein, as well as the cyclin dependent kinase inhibitor p21cip1. Following co-culture with CD4+CD25+cells, we observed up-regulation of p21cip1 and cyclin E, with down-regulation of cyclin D3, in CD8+ cells from FIV+ cats. As expected, CD8+ targets from control cats were quiescent with little up-regulation of p21cip1 and cyclin E. There was also a lack of Rb phosphorylation in CD8+ targets consistent with late G1 cell cycle arrest. Further, IL-2 mRNA was down regulated in CD8+ cells after co-culture with CD4+CD25+ Treg cells. Following CD4+CD25+ co-culture, CD8+ targets from FIV+ cats also had increased Foxp3 mRNA expression; however, these CD8+Foxp3+ cells did not exhibit suppressor function. Conclusions Collectively, these data suggest that CD4+CD25+ Treg cells from FIV+ cats induce CD8+ anergy by disruption of normal G1 to S cell cycle progression.

  14. Forced LIGHT expression in prostate tumors overcomes Treg mediated immunosuppression and synergizes with a prostate tumor therapeutic vaccine by recruiting effector T lymphocytes.

    Science.gov (United States)

    Yan, Lisa; Da Silva, Diane M; Verma, Bhavna; Gray, Andrew; Brand, Heike E; Skeate, Joseph G; Porras, Tania B; Kanodia, Shreya; Kast, W Martin

    2015-02-15

    LIGHT, a ligand for lymphotoxin-β receptor (LTβR) and herpes virus entry mediator, is predominantly expressed on activated immune cells and LTβR signaling leads to the recruitment of lymphocytes. The interaction between LIGHT and LTβR has been previously shown to activate immune cells and result in tumor regression in a virally-induced tumor model, but the role of LIGHT in tumor immunosuppression or in a prostate cancer setting, where self antigens exist, has not been explored. We hypothesized that forced expression of LIGHT in prostate tumors would shift the pattern of immune cell infiltration toward an anti-tumoral milieu, would inhibit T regulatory cells (Tregs) and would induce prostate cancer tumor associated antigen (TAA) specific T cells that would eradicate tumors. Real Time PCR was used to evaluate expression of forced LIGHT and other immunoregulatory genes in prostate tumors samples. For in vivo studies, adenovirus encoding murine LIGHT was injected intratumorally into TRAMP-C2 prostate cancer cell tumor bearing mice. Chemokine and cytokine concentrations were determined by multiplex ELISA. Flow cytometry was used to phenotype tumor infiltrating lymphocytes and expression of LIGHT on the tumor cell surface. Tumor-specific lymphocytes were quantified via ELISpot assay. Treg induction and Treg suppression assays determined Treg functionality after LIGHT treatment. LIGHT in combination with a therapeutic vaccine, PSCA TriVax, reduced tumor burden. LIGHT expression peaked within 48 hr of infection, recruited effector T cells that recognized mouse prostate stem cell antigen (PSCA) into the tumor microenvironment, and inhibited infiltration of Tregs. Tregs isolated from tumor draining lymph nodes had impaired suppressive capability after LIGHT treatment. Forced LIGHT treatment combined with PSCA TriVax therapeutic vaccination delays prostate cancer progression in mice by recruiting effector T lymphocytes to the tumor and inhibiting Treg mediated

  15. Differential Effects of Peptidoglycan Recognition Proteins on Experimental Atopic and Contact Dermatitis Mediated by Treg and Th17 Cells

    Science.gov (United States)

    Park, Shin Yong; Gupta, Dipika; Kim, Chang H.; Dziarski, Roman

    2011-01-01

    Skin protects the body from the environment and is an important component of the innate and adaptive immune systems. Atopic dermatitis and contact dermatitis are among the most frequent inflammatory skin diseases and are both determined by multigenic predisposition, environmental factors, and aberrant immune response. Peptidoglycan Recognition Proteins (Pglyrps) are expressed in the skin and we report here that they modulate sensitivity to experimentally-induced atopic dermatitis and contact dermatitis. Pglyrp3 −/− and Pglyrp4 −/− mice (but not Pglyrp2 −/− mice) develop more severe oxazolone-induced atopic dermatitis than wild type (WT) mice. The common mechanism underlying this increased sensitivity of Pglyrp3 −/− and Pglyrp4 −/− mice to atopic dermatitis is reduced recruitment of Treg cells to the skin and enhanced production and activation Th17 cells in Pglyrp3 −/− and Pglyrp4 −/− mice, which results in more severe inflammation and keratinocyte proliferation. This mechanism is supported by decreased inflammation in Pglyrp3 −/− mice following in vivo induction of Treg cells by vitamin D or after neutralization of IL-17. By contrast, Pglyrp1 −/− mice develop less severe oxazolone-induced atopic dermatitis and also oxazolone-induced contact dermatitis than WT mice. Thus, Pglyrp3 and Pglyrp4 limit over-activation of Th17 cells by promoting accumulation of Treg cells at the site of chronic inflammation, which protects the skin from exaggerated inflammatory response to cell activators and allergens, whereas Pglyrp1 has an opposite pro-inflammatory effect in the skin. PMID:21949809

  16. [Imiquimod combined with dendritic cell vaccine decreases Treg proportion and enhances anti-tumor responses in mice bearing melanoma].

    Science.gov (United States)

    Ren, Shurong; Wang, Qiubo; Zhang, Yanli; Lu, Cuixiu; Li, Ping; Li, Yumei

    2017-02-01

    Objective To investigate the therapeutic effect of Toll-like receptor 7 (TLR7) agonist imiquimod combined with dendritic cell (DC)-based tumor vaccine on melanoma in mice and the potential mechanism. Methods Melanoma-bearing mouse models were established by subcutanous injection of B16-OVA cells into C57BL/6 mice. DCs were isolated from mouse bone marrow and propagated in culture medium with recombinant mouse granulocyte-macrophage colony-stimulating factor (rmGM-CSF) and recombinant mouse interleukin-4 (rmIL-4). DC vaccine (OVA-DC) was prepared by overnight incubation of DCs added with chicken ovalbumin. C57BL/6 mice were separated into four groups which were treated with PBS, topical imiquimod application, OVA-DC intradermal injection and imiquimod plus OVA-DC, respectively. The tumor size was calculated by digital vernier caliper. Peripheral blood CD4 + FOXP3 + Tregs of the tumor-bearing mice was detected by flow cytometry. The cytotoxicity of splenic lymphocyte against B16-OVA was assessed in vitro by CCK-8 assay. Results Compared with the other three groups, B16-OVA-bearing mice treated with imiquimod plus DC vaccine had the smallest tumor volume. The percentage of CD4 + FOXP3 + Tregs decreased significantly in the combined treated mice. The combined treatment enhanced significantly cytotoxicity of splenic lymphocytes against B16-OVA cells. Conclusion Imiquimod combined with antigen-pulsed-DC vaccine could reduce CD4 + FOXP3 + Treg proportion and promote anti-tumor effect in mice with melanoma.

  17. Therapeutic targeting of regulatory T cells enhances tumor-specific CD8+ T cell responses in Epstein–Barr virus associated nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Fogg, Mark; Murphy, John R.; Lorch, Jochen; Posner, Marshall; Wang, Fred

    2013-01-01

    Epstein–Barr virus (EBV) is associated with multiple malignancies including nasopharyngeal carcinoma (NPC). In nasopharynx cancer, CD8+ T cells specific for EBV Nuclear Antigen-1 (EBNA-1) and Latent Membrane Protein 2 (LMP2) are important components of anti-tumor immunity since both are consistently expressed in NPC. We have previously shown that EBNA-1-specific CD8+ T cell responses were suppressed in NPC patients compared to healthy controls. We now find that CD8+ T cell responses specific for LMP2 are also abnormal in NPC patients, and both EBNA-1- and LMP2-specific responses are suppressed by regulatory T cells (Treg). EBNA-1 and LMP2-specific CD8+ T cell responses, as well as immune control of EBV-infected cells in vitro, could be restored by the depletion of Tregs and by use of a clinically approved drug targeting Tregs. Thus, in vivo modulation of Tregs may be an effective means of enhancing these anti-tumor immune responses in NPC patients. - Highlights: • Viral proteins are tumor antigens in Epstein–Barr virus associated Nasopharyngeal Carcinoma. • CD8+ T cell responses against EBV proteins EBNA-1 and LMP2 are suppressed in NPC patients. • T regulatory cells are responsible for suppressing EBV immunity in NPC patients. • Depletion of Tregs with Ontak can rescue EBV-specific CD8+ T cell responses in NPC patients. • This clinically approved drug may be effective for enhancing anti-tumor immunity in NPC patients

  18. Therapeutic targeting of regulatory T cells enhances tumor-specific CD8+ T cell responses in Epstein–Barr virus associated nasopharyngeal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Fogg, Mark [Department of Medicine, Brigham and Women' s Hospital (United States); Murphy, John R. [Departments of Medicine and Microbiology, Boston University School of Medicine, Boston, MA 02118 (United States); Lorch, Jochen; Posner, Marshall [Department of Adult Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115 (United States); Wang, Fred, E-mail: fwang@research.bwh.harvard.edu [Department of Medicine, Brigham and Women' s Hospital (United States); Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115 (United States)

    2013-07-05

    Epstein–Barr virus (EBV) is associated with multiple malignancies including nasopharyngeal carcinoma (NPC). In nasopharynx cancer, CD8+ T cells specific for EBV Nuclear Antigen-1 (EBNA-1) and Latent Membrane Protein 2 (LMP2) are important components of anti-tumor immunity since both are consistently expressed in NPC. We have previously shown that EBNA-1-specific CD8+ T cell responses were suppressed in NPC patients compared to healthy controls. We now find that CD8+ T cell responses specific for LMP2 are also abnormal in NPC patients, and both EBNA-1- and LMP2-specific responses are suppressed by regulatory T cells (Treg). EBNA-1 and LMP2-specific CD8+ T cell responses, as well as immune control of EBV-infected cells in vitro, could be restored by the depletion of Tregs and by use of a clinically approved drug targeting Tregs. Thus, in vivo modulation of Tregs may be an effective means of enhancing these anti-tumor immune responses in NPC patients. - Highlights: • Viral proteins are tumor antigens in Epstein–Barr virus associated Nasopharyngeal Carcinoma. • CD8+ T cell responses against EBV proteins EBNA-1 and LMP2 are suppressed in NPC patients. • T regulatory cells are responsible for suppressing EBV immunity in NPC patients. • Depletion of Tregs with Ontak can rescue EBV-specific CD8+ T cell responses in NPC patients. • This clinically approved drug may be effective for enhancing anti-tumor immunity in NPC patients.

  19. Hypomethylation of the Treg-Specific Demethylated Region in FOXP3 Is a Hallmark of the Regulatory T-cell Subtype in Adult T-cell Leukemia.

    Science.gov (United States)

    Shimazu, Yayoi; Shimazu, Yutaka; Hishizawa, Masakatsu; Hamaguchi, Masahide; Nagai, Yuya; Sugino, Noriko; Fujii, Sumie; Kawahara, Masahiro; Kadowaki, Norimitsu; Nishikawa, Hiroyoshi; Sakaguchi, Shimon; Takaori-Kondo, Akifumi

    2016-02-01

    Adult T-cell leukemia (ATL) is an aggressive T-cell malignancy caused by human T-cell leukemia virus type 1. Because of its immunosuppressive property and resistance to treatment, patients with ATL have poor prognoses. ATL cells possess the regulatory T cell (Treg) phenotype, such as CD4 and CD25, and usually express forkhead box P3 (FOXP3). However, the mechanisms of FOXP3 expression and its association with Treg-like characteristics in ATL remain unclear. Selective demethylation of the Treg-specific demethylated region (TSDR) in the FOXP3 gene leads to stable FOXP3 expression and defines natural Tregs. Here, we focus on the functional and clinical relationship between the epigenetic pattern of the TSDR and ATL. Analysis of DNA methylation in specimens from 26 patients with ATL showed that 15 patients (58%) hypomethylated the TSDR. The FOXP3(+) cells were mainly observed in the TSDR-hypomethylated cases. The TSDR-hypomethylated ATL cells exerted more suppressive function than the TSDR-methylated ATL cells. Thus, the epigenetic analysis of the FOXP3 gene identified a distinct subtype with Treg properties in heterogeneous ATL. Furthermore, we observed that the hypomethylation of TSDR was associated with poor outcomes in ATL. These results suggest that the DNA methylation status of the TSDR is an important hallmark to define this heterogeneous disease and to predict ATL patient prognosis. ©2015 American Association for Cancer Research.

  20. Roquin Suppresses the PI3K-mTOR Signaling Pathway to Inhibit T Helper Cell Differentiation and Conversion of Treg to Tfr Cells.

    Science.gov (United States)

    Essig, Katharina; Hu, Desheng; Guimaraes, Joao C; Alterauge, Dominik; Edelmann, Stephanie; Raj, Timsse; Kranich, Jan; Behrens, Gesine; Heiseke, Alexander; Floess, Stefan; Klein, Juliane; Maiser, Andreas; Marschall, Susan; Hrabĕ de Angelis, Martin; Leonhardt, Heinrich; Calkhoven, Cornelis F; Noessner, Elfriede; Brocker, Thomas; Huehn, Jochen; Krug, Anne B; Zavolan, Mihaela; Baumjohann, Dirk; Heissmeyer, Vigo

    2017-12-19

    Roquin proteins preclude spontaneous T cell activation and aberrant differentiation of T follicular helper (Tfh) or T helper 17 (Th17) cells. Here we showed that deletion of Roquin-encoding alleles specifically in regulatory T (Treg) cells also caused the activation of conventional T cells. Roquin-deficient Treg cells downregulated CD25, acquired a follicular Treg (Tfr) cell phenotype, and suppressed germinal center reactions but could not protect from colitis. Roquin inhibited the PI3K-mTOR signaling pathway by upregulation of Pten through interfering with miR-17∼92 binding to an overlapping cis-element in the Pten 3' UTR, and downregulated the Foxo1-specific E3 ubiquitin ligase Itch. Loss of Roquin enhanced Akt-mTOR signaling and protein synthesis, whereas inhibition of PI3K or mTOR in Roquin-deficient T cells corrected enhanced Tfh and Th17 or reduced iTreg cell differentiation. Thereby, Roquin-mediated control of PI3K-mTOR signaling prevents autoimmunity by restraining activation and differentiation of conventional T cells and specialization of Treg cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Cyclic AMP-Responsive Element-Binding Protein (CREB is Critical in Autoimmunity by Promoting Th17 but Inhibiting Treg Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Xiaohu Wang

    2017-11-01

    Full Text Available The molecular mechanisms that govern differential T cell development into pro-inflammatory Th17 vs. regulatory T (Treg cells remain unclear. Here, we show that selective deletion of CREB in T cells or Th17 cells impaired Th17 cell differentiation in vitro and in vivo, and led to resistance to autoimmune diseases. Mechanistically, CREB, activated by CD3-PKC-ϴ signaling, plays a key role in regulating Th17 cell differentiation, at least in part through directly binding to the Il17-Il17f gene locus. Unexpectedly, although dispensable for FOXP3 expression and for the homeostasis and suppressive function of thymus-derived Treg cells, CREB negatively regulates the survival of TGF-β-induced Treg cells, and deletion of CREB resulted in increased FOXP3+ Treg cells in the intestine and protection in a colitis model. Thus, CREB is critical in autoimmune diseases by promoting Th17 cell and inhibiting de novo Treg cell generation.

  2. [Effect of Electroacupuncture Stimulation of "Guanyuan" (CV 4) and "Zusanli" (ST 36) on Spleen Lymphocytes Treg/Th 17 Immune Balance in Ulcerative Colitis Mice].

    Science.gov (United States)

    Wang, Cheng-yu-lin; Zeng, Lin-lan; Geng, Yu; Wang, Xiang; Zhang, He-jiao; Yang, Hui; Wu, Qiao- feng; Yu, Shu-guang

    2016-02-01

    To observe the effect of electroacupuncture (EA) intervention on spleen T-helper 17 (Th 17) and regulatory T (Treg) cell levels in mice with ulcerative colitis (UC), so as to reveal its mechanisms underlying improvement of UC. METHODS Kunming mice were randomized into control, UC model and EA groups, with 8 mice in each group. The UC model was established by giving the mice with 3% Dextran Sulfate Sodium (DSS) for 5 days. EA (15 Hz/25 Hz, 0.1-0.2 mA) was applied at "Guanyuan" (CV 4) and bilateral "Zusanli" (ST 36, used alternatively) for 10 min, once a day for 5 days. The animals' disease activity index [DAl, = (body weight index score + stool score + bleeding score)/3; 0-4 points] were calculated. The pathological changes of colon tissues were observed by light microscopy after H. E. stain, and spleen Treg (CD⁴⁺ CD²⁵⁺ Foxp³⁺ Treg) and Th 17 (CD³⁺ CD⁸⁺ IL-17⁺ Th 17) lymphocyte levels were determined by flow cytometry. Compared to the control group, the DAl score and the ratio of Th 17/CD⁸⁺ T cells were significantly increased, while the ratio of Treg/CD⁴⁺ T cells obviously decreased in the model group (P Th 17/CD⁸⁺ T cells and the decreased Treg/CD⁴⁺ T cells were reversed (P Th 17 lymphocytes.

  3. Lactobacillus salivarius Isolated from Patients with Rheumatoid Arthritis Suppresses Collagen-Induced Arthritis and Increases Treg Frequency in Mice.

    Science.gov (United States)

    Liu, Xiaofei; Zhang, Juan; Zou, Qinghua; Zhong, Bing; Wang, Heng; Mou, Fangxiang; Wu, Like; Fang, Yongfei

    2016-12-01

    Previously, we demonstrated that Lactobacillus salivarius was more abundant in patients with rheumatoid arthritis (RA), an inflammatory autoimmune disease wherein the gut microbiota is altered, than in healthy individuals. However, the effect of L. salivarius in RA is unclear. Hence, we investigated the effect of L. salivarius isolated from patients with RA on collagen-induced arthritis (CIA) in mice. L. salivarius UCC118 or L. plantarum WCFS1 isolated from patients with RA was administered orally for 5 weeks, starting from 2 weeks before the induction of arthritis in DBA/1 mice. Clinical score progression, histological changes, serum cytokine concentrations, and the proportion of interleukin (IL)-17-producing T cells [T helper 17 (Th17)] and regulatory T cells (Tregs) in the spleen were evaluated. Bone erosion was evaluated by micro-computed tomography. CIA mice treated with either L. salivarius or L. plantarum showed lower arthritis scores, milder synovial infiltration, and less bone erosion when compared with phosphate-buffered, saline-treated CIA mice. Administration of L. salivarius and L. plantarum reduced the Th17 cell fraction and increased the Treg fraction. L. salivarius-treated CIA mice displayed a significant increase in serum anti-inflammatory IL-10 levels. Thus, pretreatment with L. salivarius could significantly improve CIA in mice and may help alleviate RA in a clinical setting.

  4. Curcumin attenuates sepsis-induced acute organ dysfunction by preventing inflammation and enhancing the suppressive function of Tregs.

    Science.gov (United States)

    Chen, Longwang; Lu, Yang; Zhao, Linjun; Hu, Lili; Qiu, Qiaomeng; Zhang, Zhuoling; Li, Mengfang; Hong, Guangliang; Wu, Bing; Zhao, Guangju; Lu, Zhongqiu

    2018-05-17

    Sepsis is characterized by the extensive release of cytokines and other mediators. It results in a dysregulated immune response and can lead to organ damage and death. Curcumin has anti-inflammatory properties and immunoregulation functions in various disorders such as sepsis, cancer, rheumatoid arthritis, cardiovascular diseases, lung fibrosis, gallstone formation, and diabetes. This paper investigates the effects of curcumin on immune status and inflammatory response in mice subjected to cecal ligation and puncture (CLP). Inflammatory tissue injury was evaluated by histological observation. Magnetic microbeads were used to isolate splenic CD4 + CD25 + regulatory T cells (Tregs), and phenotypes were then analyzed by flow cytometry. The levels of Foxp3 were detected by Western blot and real-time PCR and cytokine levels were determined by enzyme-linked immunosorbent assay. We found that the administration of curcumin significantly alleviated inflammatory injury of the lung and kidney in septic mice. The suppressive function of Treg cells was enhanced and the plasma levels of IL-10 increased after treatment with curcumin. Furthermore, the secretion of plasma TNF-α and IL-6 was notably inhibited in septic mice treated with curcumin and administration with curcumin could improve survival after CLP. These data suggest that curcumin could be used as a potential therapeutic agent for sepsis. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Interactions between Th1 cells and Tregs affect regulation of hepatic fibrosis in biliary atresia through the IFN-γ/STAT1 pathway.

    Science.gov (United States)

    Wen, Jie; Zhou, Ying; Wang, Jun; Chen, Jie; Yan, Wenbo; Wu, Jin; Yan, Junkai; Zhou, Kejun; Xiao, Yongtao; Wang, Yang; Xia, Qiang; Cai, Wei

    2017-06-01

    Regulatory T cells (Tregs) and CD4 + T helper (Th) cells have important roles in bile duct injury of biliary atresia (BA). However, their impacts on liver fibrosis are undefined. Between 2013 and 2016, 146 patients with various stages of BA were enrolled in this study. Peripheral blood, liver biopsy and lymph node samples were collected. Flow cytometry, magnetic cell sorting and immunostaining were used to characterize lymphocytes from BA patients. Deficiency of Tregs was observed along with increased Th1, Th2 and Th17 frequencies in the peripheral blood and livers of BA patients. The levels of peripheral and intrahepatic Th1 cells positively correlated with the stage of liver fibrosis. Furthermore, Th1 cells were located in close proximity to activated hepatic stellate cells (HSCs) and areas of fibrosis in BA livers. In culture, Th1 cells accelerated the proliferation and secretion of profibrogenic markers of HSCs through the IFN-γ/STAT1 pathway. Of note, Tregs blocked the Th1-stimulated effects on HSCs by inhibiting Th1-induced activation of STAT1. Consistent with the results of in vitro study, intrahepatic IFN-γ/STAT1 levels increased in relation to the severity of liver fibrosis in BA patients, and the altered balance between MMP2 and TIMP1 expressions in livers may contribute to increased deposition of extracellular matrix and fibrosis. Finally, to identify the effects of Th1 cells on Tregs, we demonstrated that Th1 cells upregulated the proportion of aTreg cells by secreting IFN-γ cytokine. Thus, aberrant Th1 immune responses in BA promote the proliferation and secretion of HSCs through the IFN-γ/STAT1 pathway. The regulation of HSCs by the interactions between Tregs and Th1 cells might be part of the mechanism underlying progressive liver fibrosis and may be a suitable target for therapy.

  6. Expression of tyrosine hydroxylase in CD4+ T cells contributes to alleviation of Th17/Treg imbalance in collagen-induced arthritis.

    Science.gov (United States)

    Wang, Xiao-Qin; Liu, Yan; Cai, Huan-Huan; Peng, Yu-Ping; Qiu, Yi-Hua

    2016-12-01

    Tyrosine hydroxylase (TH), a rate-limiting enzyme for the synthesis of catecholamines, is expressed in T lymphocytes. However, the role of T cell-expressed TH in rheumatoid arthritis (RA) is less clear. Herein, we aimed to show the contribution of TH expression by CD4 + T cells to alleviation of helper T (Th)17/regulatory T (Treg) imbalance in collagen-induced arthritis (CIA), a mouse model of RA. CIA was prepared by intradermal injection of collagen type II (CII) at tail base of DBA1/J mice. Expression of TH in the spleen and the ankle joints was measured by real-time polymerase chain reaction and Western blot analysis. Percentages of TH-expressing Th17 and Treg cells in splenic CD4 + T cells were determined by flow cytometry. Overexpression and knockdown of TH gene in CD4 + T cells were taken to evaluate effects of TH on Th17 and Treg cells in CIA. TH expression was upregulated in both the inflamed tissues (spleen and ankle joints) and the CD4 + T cells of CIA mice. In splenic CD4 + T cells, the cells expressing TH were increased during CIA. These cells that expressed more TH in CIA were mainly Th17 cells rather than Treg cells. TH gene overexpression in CD4 + T cells from CIA mice reduced Th17 cell percentage as well as Th17-related transcription factor and cytokine expression and secretion, whereas TH gene knockdown enhanced the Th17 cell activity. In contrast, TH gene overexpression increased Treg-related cytokine expression and secretion in CD4 + T cells of CIA mice, while TH gene knockdown decreased the Treg cell changes. Collectively, these findings show that CIA induces TH expression in CD4 + T cells, particularly in Th17 cells, and suggest that the increased TH expression during CIA represents an anti-inflammatory mechanism.

  7. Sex bias in experimental immune-mediated, drug-induced liver injury in BALB/c mice: suggested roles for Tregs, estrogen, and IL-6.

    Directory of Open Access Journals (Sweden)

    Joonhee Cho

    Full Text Available Immune-mediated, drug-induced liver injury (DILI triggered by drug haptens is more prevalent in women than in men. However, mechanisms responsible for this sex bias are not clear. Immune regulation by CD4+CD25+FoxP3+ regulatory T-cells (Tregs and 17β-estradiol is crucial in the pathogenesis of sex bias in cancer and autoimmunity. Therefore, we investigated their role in a mouse model of immune-mediated DILI.To model DILI, we immunized BALB/c, BALB/cBy, IL-6-deficient, and castrated BALB/c mice with trifluoroacetyl chloride-haptenated liver proteins. We then measured degree of hepatitis, cytokines, antibodies, and Treg and splenocyte function.BALB/c females developed more severe hepatitis (p<0.01 and produced more pro-inflammatory hepatic cytokines and antibodies (p<0.05 than did males. Castrated males developed more severe hepatitis than did intact males (p<0.001 and females (p<0.05. Splenocytes cultured from female mice exhibited fewer Tregs (p<0.01 and higher IL-1β (p<0.01 and IL-6 (p<0.05 than did those from males. However, Treg function did not differ by sex, as evidenced by absence of sex bias in programmed death receptor-1 and responses to IL-6, anti-IL-10, anti-CD3, and anti-CD28. Diminished hepatitis in IL-6-deficient, anti-IL-6 receptor α-treated, ovariectomized, or male mice; undetectable IL-6 levels in splenocyte supernatants from ovariectomized and male mice; elevated splenic IL-6 and serum estrogen levels in castrated male mice, and IL-6 induction by 17β-estradiol in splenocytes from naïve female mice (p<0.05 suggested that 17β-estradiol may enhance sex bias through IL-6 induction, which subsequently discourages Treg survival. Treg transfer from naïve female mice to those with DILI reduced hepatitis severity and hepatic IL-6.17β-estradiol and IL-6 may act synergistically to promote sex bias in experimental DILI by reducing Tregs. Modulating Treg numbers may provide a therapeutic approach to DILI.

  8. High Level of Tregs Is a Positive Prognostic Marker in Patients with HPV-Positive Oral and Oropharyngeal Squamous Cell Carcinomas

    Czech Academy of Sciences Publication Activity Database

    Lukešová, E.; Bouček, J.; Rotnáglová, E.; Salaková, M.; Koslabová, E.; Grega, M.; Eckschlager, T.; Říhová, Blanka; Procházka, B.; Klozar, J.; Tachezy, R.

    2014-01-01

    Roč. 2, č. 303929 (2014), 1-4 ISSN 2314-6141 R&D Projects: GA MZd(CZ) NT11542 Grant - others:GA UK(CZ) SVV 266513 Institutional support: RVO:61388971 Keywords : HPV positivity * Tregs * Infection Subject RIV: EE - Microbiology, Virology

  9. LAP TGF-Beta Subset of CD4+CD25+CD127− Treg Cells is Increased and Overexpresses LAP TGF-Beta in Lung Adenocarcinoma Patients

    Science.gov (United States)

    Islas-Vazquez, Lorenzo; Aguilar-Cazares, Dolores; Meneses-Flores, Manuel; Galicia-Velasco, Miriam; Romero-Garcia, Susana; Camacho-Mendoza, Catalina; Lopez-Gonzalez, Jose Sullivan

    2015-01-01

    Lung cancer is the leading cause of cancer death worldwide. Adenocarcinoma, the most commonly diagnosed histologic type of lung cancer, is associated with smoking. Cigarette smoke promotes inflammation on the airways, which might be mediated by Th17 cells. This inflammatory environment may contribute to tumor development. In contrast, some reports indicate that tumors may induce immunosuppressive Treg cells to dampen immune reactivity, supporting tumor growth and progression. Thus, we aimed to analyze whether chronic inflammation or immunosuppression predominates at the systemic level in lung adenocarcinoma patients, and several cytokines and Th17 and Treg cells were studied. Higher proportions of IL-17-producing CD4+ T-cells were found in smoking control subjects and in lung adenocarcinoma patients compared to nonsmoking control subjects. In addition, lung adenocarcinoma patients increased both plasma concentrations of IL-2, IL-4, IL-6, and IL-10, and proportions of Latency Associated Peptide (LAP) TGF-β subset of CD4+CD25+CD127− Treg cells, which overexpressed LAP TGF-β. This knowledge may lead to the development of immunotherapies that could inhibit the suppressor activity mediated by the LAP TGF-β subset of CD4+CD25+CD127− Treg cells to promote reactivity of immune cells against lung adenocarcinoma cells. PMID:26582240

  10. Expression of Foxp3 in colorectal cancer but not in Treg cells correlates with disease progression in patients with colorectal cancer.

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    Mia Kim

    Full Text Available BACKGROUND: Regulatory T cells (Treg expressing the transcription factor forkhead-box protein P3 (Foxp3 have been identified to counteract anti-tumor immune responses during tumor progression. Besides, Foxp3 presentation by cancer cells itself may also allow them to evade from effector T-cell responses, resulting in a survival benefit of the tumor. For colorectal cancer (CRC the clinical relevance of Foxp3 has not been evaluated in detail. Therefore the aim of this study was to study its impact in colorectal cancer (CRC. METHODS AND FINDINGS: Gene and protein analysis of tumor tissues from patients with CRC was performed to quantify the expression of Foxp3 in tumor infiltrating Treg and colon cancer cells. The results were correlated with clinicopathological parameters and patients overall survival. Serial morphological analysis demonstrated Foxp3 to be expressed in cancer cells. High Foxp3 expression of the cancer cells was associated with poor prognosis compared to patients with low Foxp3 expression. In contrast, low and high Foxp3 level in tumor infiltrating Treg cells demonstrated no significant differences in overall patient survival. CONCLUSIONS: Our findings strongly suggest that Foxp3 expression mediated by cancer cells rather than by Treg cells contribute to disease progression.

  11. Increased Tregs associated with elevated Indoleamine-2,3-dioxygenase activity and an imbalanced Kynurenine pathway in IFNpositive primary Sjögren's syndrome

    NARCIS (Netherlands)

    N.I. Maria (Naomi); C.G. van Helden-Meeuwsen; Z. Brkić (Zana); S.M.J. Paulissen (Sandra); E.C. Steenwijk (Eline); V.A.S.H. Dalm (Virgil); P.L.A. van Daele (Paul); M.P. van Hagen (Martin); F.G.M. Kroese (Frans G.); J.A.G. van Roon (J. A G); A. Harkin (Andrew); A.W. Dik (Willem); H.A. Drexhage (Hemmo); E.W. Lubberts (Erik); M.A. Versnel (Marjan)

    2016-01-01

    textabstractIntroduction Indoleamine-2,3-dioxygenase (IDO), the rate-limiting enzyme converting tryptophan (TRP) to kynurenine (KYN), is driven in part by type I/II IFNs. Naïve T cells are polarized into FoxP3+ regulatory T cells (Tregs) upon exposure to either IDO+ cells or KYN. Recent studies

  12. Dynamics of antigen presentation to transgene product-specific CD4+ T cells and of Treg induction upon hepatic AAV gene transfer

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    George Q Perrin

    2016-01-01

    Full Text Available The tolerogenic hepatic microenvironment impedes clearance of viral infections but is an advantage in viral vector gene transfer, which often results in immune tolerance induction to transgene products. Although the underlying tolerance mechanism has been extensively studied, our understanding of antigen presentation to transgene product-specific CD4+ T cells remains limited. To address this, we administered hepatotropic adeno-associated virus (AAV8 vector expressing cytoplasmic ovalbumin (OVA into wt mice followed by adoptive transfer of transgenic OVA-specific T cells. We find that that the liver-draining lymph nodes (celiac and portal are the major sites of MHC II presentation of the virally encoded antigen, as judged by in vivo proliferation of DO11.10 CD4+ T cells (requiring professional antigen-presenting cells, e.g., macrophages and CD4+CD25+FoxP3+ Treg induction. Antigen presentation in the liver itself contributes to activation of CD4+ T cells egressing from the liver. Hepatic-induced Treg rapidly disseminate through the systemic circulation. By contrast, a secreted OVA transgene product is presented in multiple organs, and OVA-specific Treg emerge in both the thymus and periphery. In summary, liver draining lymph nodes play an integral role in hepatic antigen presentation and peripheral Treg induction, which results in systemic regulation of the response to viral gene products.

  13. The Th1/Th2/Th17/Treg paradigm induced by stachydrine hydrochloride reduces uterine bleeding in RU486-induced abortion mice.

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    Li, Xia; Wang, Bin; Li, Yuzhu; Wang, Li; Zhao, Xiangzhong; Zhou, Xianbin; Guo, Yuqi; Jiang, Guosheng; Yao, Chengfang

    2013-01-09

    The Th1/Th2/Th17/Treg paradigm plays an important role in achieving maternal-fetal immunotolerance and participates in RU486-induced abortion. Excessive uterine bleeding is the most common side effect of RU486-induced abortion; however, its etiopathogenesis has not been fully understood. Therefore, elucidating the correlation between the Th1/Th2/Th17/Treg paradigm and the volume of uterine bleeding may offer novel therapeutic target for reducing uterine bleeding in RU486-induced abortion. Leonurus sibiricus has been used in clinics to reduce postpartum hemorrhage with low toxicity and high efficiency; however, the effective constituents and therapeutic mechanism have not been described. Stachydrine hydrochloride is the main constituent of L. sibiricus, therefore L. sibiricus is regarded as a candidate for reducing uterine bleeding in RU486-induced abortion mice by regulating the Th1/Th2/Th17/Treg paradigm. The purpose of this study was to determine the Th1/Th2/Th17/Treg paradigm in uterine bleeding of RU486-induced abortion mice and to elucidate the immunopharmacologic effects of stachydrine hydrochloride on inducing the Th1/Th2/Th17/Treg paradigm in reducing the uterine bleeding volume in RU486-induced abortion mice. To investigate the Th1/Th2/Th17/Treg paradigm in uterine bleeding during RU486-induced abortion mice, pregnant BALB/c mice were treated with high- and low-dose RU486 (1.5mg/kg and 0.9 mg/kg, respectively), and the serum progesterone (P(4)) protein level, uterine bleeding volume, and proportions of Th1/Th2/Th17/Treg cells in mice at the maternal-fetal interface were detected by ELISA assay, alkaline hematin photometric assay, and flow cytometry, respectively. To determine the regulatory effect of stachydrine hydrochloride on the Th1/Th2/Th17/Treg paradigm in vitro, splenocytes of non-pregnant mice were separated and treated with P(4,) RU486, and/or stachydrine hydrochloride (10(-5)M, 10(-4)M, and 10(-3)M, respectively). The proportions of Th1/Th2/Th17

  14. LAP TGF-Beta Subset of CD4+CD25+CD127− Treg Cells is Increased and Overexpresses LAP TGF-Beta in Lung Adenocarcinoma Patients

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    Lorenzo Islas-Vazquez

    2015-01-01

    Full Text Available Lung cancer is the leading cause of cancer death worldwide. Adenocarcinoma, the most commonly diagnosed histologic type of lung cancer, is associated with smoking. Cigarette smoke promotes inflammation on the airways, which might be mediated by Th17 cells. This inflammatory environment may contribute to tumor development. In contrast, some reports indicate that tumors may induce immunosuppressive Treg cells to dampen immune reactivity, supporting tumor growth and progression. Thus, we aimed to analyze whether chronic inflammation or immunosuppression predominates at the systemic level in lung adenocarcinoma patients, and several cytokines and Th17 and Treg cells were studied. Higher proportions of IL-17-producing CD4+ T-cells were found in smoking control subjects and in lung adenocarcinoma patients compared to nonsmoking control subjects. In addition, lung adenocarcinoma patients increased both plasma concentrations of IL-2, IL-4, IL-6, and IL-10, and proportions of Latency Associated Peptide (LAP TGF-β subset of CD4+CD25+CD127− Treg cells, which overexpressed LAP TGF-β. This knowledge may lead to the development of immunotherapies that could inhibit the suppressor activity mediated by the LAP TGF-β subset of CD4+CD25+CD127− Treg cells to promote reactivity of immune cells against lung adenocarcinoma cells.

  15. Gastric cancer tissue-derived mesenchymal stem cells impact peripheral blood mononuclear cells via disruption of Treg/Th17 balance to promote gastric cancer progression.

    Science.gov (United States)

    Wang, Mei; Chen, Bin; Sun, Xiao-Xian; Zhao, Xiang-Dong; Zhao, Yuan-Yuan; Sun, Li; Xu, Chang-Gen; Shen, Bo; Su, Zhao-Liang; Xu, Wen-Rong; Zhu, Wei

    2017-12-01

    Gastric cancer tissue-derived mesenchymal stem cells (GC-MSCs) are important resident stromal cells in the tumor microenvironment (TME) and have been shown to play a key role in gastric cancer progression. Whether GC-MSCs exert a tumor-promoting function by affecting anti-tumor immunity is still unclear. In this study, we used GC-MSC conditioned medium (GC-MSC-CM) to pretreat peripheral blood mononuclear cells (PBMCs) from healthy donors. We found that GC-MSC-CM pretreatment markedly reversed the inhibitory effect of PBMCs on gastric cancer growth in vivo, but did not affect functions of PBMCs on gastric cancer cell proliferation, cell cycle and apoptosis in vitro. PBMCs pretreated with GC-MSC-CM significantly promoted gastric cancer migration and epithelial-mesenchymal transition in vitro and liver metastases in vivo. Flow cytometry analysis showed that GC-MSC-CM pretreatment increased the proportion of Treg cells and reduced that of Th17 cells in PBMCs. CFSE labeling and naïve CD4 + T cells differentiation analysis revealed that GC-MSC-CM disrupted the Treg/Th17 balance in PBMCs by suppressing Th17 cell proliferation and inducing differentiation of Treg cells. Overall, our collective results indicate that GC-MSCs impair the anti-tumor immune response of PBMCs through disruption of Treg/Th17 balance, thus providing new evidence that gastric cancer tissue-derived MSCs contribute to the immunosuppressive TME. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Reishi Protein LZ-8 Induces FOXP3+ Treg Expansion via a CD45-Dependent Signaling Pathway and Alleviates Acute Intestinal Inflammation in Mice

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    Hsien-Yeh Hsu

    2013-01-01

    Full Text Available LZ-8, an immunomodulatory protein isolated from Ganoderma lucidum (also known as Ling-Zhi or Reishi, has been shown to promote cell proliferation and IL-2 production in T cells. In this study, we show that LZ-8 induces the expansion of both murine and human CD4+ T cells into FOXP3+ regulatory T (Treg cells. LZ-8 treatment was found to stimulate a 4-fold and a 10-fold expansion in the Treg populations of murine and human primary CD4+ T cells, respectively. In addition, the expression of CTLA-4 and IL-10 was induced in LZ-8-treated CD4+ T cells. Using neutralizing antibodies and gene-deficient T-cell lines, we also found that LZ-8 promotes Treg expansion through a CD45-mediated signaling pathway and that the CD18-dependent induction of IL-2 was involved in Treg formation and IL-10 production. The suppressive activity of LZ-8 was confirmed using a murine model of DSS-induced colitis; the disease was alleviated by the adoptive transfer of LZ-8-treated CD4+ T cells. In conclusion, a new regulatory function for LZ-8 was identified, and the molecular mechanisms underlying this function were elucidated.

  17. Local induction of immunosuppressive CD8+ T cells in the gut-associated lymphoid tissues.

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    Diana Fleissner

    Full Text Available BACKGROUND: In contrast to intestinal CD4(+ regulatory T cells (T(regs, the generation and function of immunomodulatory intestinal CD8(+ T cells is less well defined. To dissect the immunologic mechanisms of CD8(+ T cell function in the mucosa, reactivity against hemagglutinin (HA expressed in intestinal epithelial cells of mice bearing a MHC class-I-restricted T-cell-receptor specific for HA was studied. METHODOLOGY AND PRINCIPAL FINDINGS: HA-specific CD8(+ T cells were isolated from gut-associated tissues and phenotypically and functionally characterized for the expression of Foxp3(+ and their suppressive capacity. We demonstrate that intestinal HA expression led to peripheral induction of HA-specific CD8(+Foxp3(+ T cells. Antigen-experienced CD8(+ T cells in this transgenic mouse model suppressed the proliferation of CD8(+ and CD4(+ T cells in vitro. Gene expression analysis of suppressive HA-specific CD8(+ T cells revealed a specific up-regulation of CD103, Nrp1, Tnfrsf9 and Pdcd1, molecules also expressed on CD4(+ T(reg subsets. Finally, gut-associated dendritic cells were able to induce HA-specific CD8(+Foxp3(+ T cells. CONCLUSION AND SIGNIFICANCE: We demonstrate that gut specific antigen presentation is sufficient to induce CD8(+ T(regsin vivo which may maintain intestinal homeostasis by down-modulating effector functions of T cells.

  18. Local induction of immunosuppressive CD8+ T cells in the gut-associated lymphoid tissues.

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    Fleissner, Diana; Hansen, Wiebke; Geffers, Robert; Buer, Jan; Westendorf, Astrid M

    2010-10-20

    In contrast to intestinal CD4(+) regulatory T cells (T(regs)), the generation and function of immunomodulatory intestinal CD8(+) T cells is less well defined. To dissect the immunologic mechanisms of CD8(+) T cell function in the mucosa, reactivity against hemagglutinin (HA) expressed in intestinal epithelial cells of mice bearing a MHC class-I-restricted T-cell-receptor specific for HA was studied. HA-specific CD8(+) T cells were isolated from gut-associated tissues and phenotypically and functionally characterized for the expression of Foxp3(+) and their suppressive capacity. We demonstrate that intestinal HA expression led to peripheral induction of HA-specific CD8(+)Foxp3(+) T cells. Antigen-experienced CD8(+) T cells in this transgenic mouse model suppressed the proliferation of CD8(+) and CD4(+) T cells in vitro. Gene expression analysis of suppressive HA-specific CD8(+) T cells revealed a specific up-regulation of CD103, Nrp1, Tnfrsf9 and Pdcd1, molecules also expressed on CD4(+) T(reg) subsets. Finally, gut-associated dendritic cells were able to induce HA-specific CD8(+)Foxp3(+) T cells. We demonstrate that gut specific antigen presentation is sufficient to induce CD8(+) T(regs)in vivo which may maintain intestinal homeostasis by down-modulating effector functions of T cells.

  19. [Zaocys type II collagen regulates mesenteric lymph node Treg/Th17 cell balance in mice with collagen-induced arthritis].

    Science.gov (United States)

    Wang, Hao; Feng, Zhitao; Zhu, Junqing; Li, Juan

    2014-05-01

    To investigate the effect of oral administration of Zaocys type II collagen (ZCII) on the percentages of Treg/Th17 cells in mesenteric lymph node lymphocytes (MLNLs) in mice with collagen-induced arthritis (CIA). CIA was induced in male C57BL/6 mice by immunization with chicken type II collagen. Three weeks later, ZCII, purified by pepsin digestion, was orally administered in the mice for 7 consecutive days (daily dose of 10, 20, or 40 µg/kg). The severity of arthritis in each limb was evaluated using a macroscopic scoring system, and histopathological changes of the joint were observed microscopically with HE staining. The percentages of Treg and Th17 cells in MLNLs was detected by flow cytometry, and the levels of transforming growth factor-β (TGF-β) and interleukin-17 (IL-17) in the supernatant of MLNLs were measured by enzyme-linked immunosorbent assay. Compared with normal control mice, the mice with CIA had significantly higher scores for arthritis and histopathological changes, with also significantly increased percentages of Treg and Th17 cells in MLNLs and elevated levels of TGF-β and IL-17 in MLNL supernatant (P<0.05). In ZCII peptide-treated mice, the scores for arthritis and histopathological changes were significantly lower than those in CIA model group (P<0.05), and Treg cell percentage in MLNLs was up-regulated while Th17 cell percentage lowered; the level of TGF-β was increased but IL-17 was decreased significantly (P<0.05). Oral administration of ZCII improves CIA in mice by regulating the percentages of Treg/Th17 cells and the cytokine levels in MLNLs, suggesting the value of ZCII as a promising candidate agent for treatment of rheumatoid arthritis.

  20. Fasciola hepatica reinfection potentiates a mixed Th1/Th2/Th17/Treg response and correlates with the clinical phenotypes of anemia

    Science.gov (United States)

    Perez-Crespo, Ignacio; Chillón-Marinas, Carlos; Khoubbane, Messaoud; Quesada, Carla; Reguera-Gomez, Marta; Mas-Coma, Santiago; Fresno, Manuel; Gironès, Núria

    2017-01-01

    Background Fascioliasis is a severe zoonotic disease of worldwide extension caused by liver flukes. In human fascioliasis hyperendemic areas, reinfection and chronicity are the norm and anemia is the main sign. Herein, the profile of the Th1/Th2/Th17/Treg expression levels is analyzed after reinfection, correlating them with their corresponding hematological biomarkers of morbidity. Methodology/Principal findings The experimental design reproduces the usual reinfection/chronicity conditions in human fascioliasis endemic areas and included Fasciola hepatica primo-infected Wistar rats (PI) and rats reinfected at 8 weeks (R8), and at 12 weeks (R12), and negative control rats. In a cross-sectional study, the expression of the genes associated with Th1 (Ifng, Il12a, Il12b, Nos2), Th2 (Il4, Arg1), Treg (Foxp3, Il10, Tgfb, Ebi3), and Th17 (Il17) in the spleen and thymus was analyzed. After 20 weeks of primary infection, PI did not present significant changes in the expression of those genes when compared to non-infected rats (NI), but an increase of Il4, Arg1 and Ifng mRNA in the spleen was observed in R12, suggesting the existence of an active mixed Th1/Th2 systemic immune response in reinfection. Foxp3, Il10, Tgfb and Ebi3 levels increased in the spleen in R12 when compared to NI and PI, indicating that the Treg gene expression levels are potentiated in chronic phase reinfection. Il17 gene expression levels in R12 in the spleen increased when compared to NI, PI and R8. Gene expression levels of Il10 in the thymus increased when compared to NI and PI in R12. Ifng expression levels in the thymus increased in all reinfected rats, but not in PI. The clinical phenotype was determined by the fluke burden, the rat body weight and the hemogram. Multivariate mathematical models were built to describe the Th1/Th2/Th17/Treg expression levels and the clinical phenotype. In reinfection, two phenotypic patterns were detected: i) one which includes only increased splenic Ifng

  1. Evaluation of PLGA containing anti-CTLA4 inhibited endometriosis progression by regulating CD4+CD25+Treg cells in peritoneal fluid of mouse endometriosis model.

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    Liu, Qi; Ma, Pingchuan; Liu, Lanxia; Ma, Guilei; Ma, Jingjing; Liu, Xiaoxuan; Liu, Yijin; Lin, Wanjun; Zhu, Yingjun

    2017-01-01

    Our study investigated poly(lactic-co-glycolic acid) (PLGA) as protein delivery vehicles encapsulate CTLA-4-antibody (anti-CTLA-4) which is essential for CD4+CD25+Treg cells suppressive function exposing superior potential for inhibiting endometriosis progress in mouse model than single anti-CTLA-4. Anti-CTLA-4 loaded PLGA combined to ligands CTLA-4 in surface of CD4+CD25+Treg cells which distributed in peritoneal fluid of mouse endometriosis model. The particle size, zeta potential of the anti-CTLA-4 loaded nanoparticles was detected by dynamic light scattering. Morphology of nanoparticles was evaluated by transmission electron microscopy (TEM). Confocal laser scanning microscopy (CLSM) indicated distribution of anti-CTLA-4 with PLGA or without in peritoneal fluid. Cumulative anti-CTLA-4 release from nanoparticles was evaluated by Micro BCA assay. The percentage of CD4+CD25+Treg cells in peritoneal fluid was demonstrated by flow cytometer. In vitro experiment we co-culture ectopic endometrial cells (EEC) with isolated CD4+CD25+Treg cells in peritoneal fluid (PF), proliferation and invasion of ectopic endometrial cells (EEC) was measured by BrdU ELISA assay and Matrigel invasion assay. In comparison with anti-CTLA-4 without nanoparticles, the bioconjugates PLGA/anti-CTLA-4 were tolerated in peritoneal fluid with a controlled release of anti-CTLA-4 in 3, 7, 14days. Moreover, PLGA/anti-CTLA-4 had superior protective regulation ability to reduce level of CD4+CD25+Treg cells in peritoneal fluid. Most strikingly, in vitro experiment, PLGA/anti-CTLA-4 exhibited better ability in inhibiting proliferation and invasion of ectopic endometrial cells in co-culture system compared with anti-CTLA-4. Progressively, PLGA/anti-CTLA-4 had better suppressive activity to inhibited IL-10 and TGF-beta secreted by CD4+CD25+Treg cells which indicating that PLGA/anti-CTLA-4 suppressed cells proliferation and invasion through reduced IL-10 and TGF-beta production. Thus, PLGA/anti-CTLA-4 may

  2. All-trans retinoic acid promotes TGF-β-induced Tregs via histone modification but not DNA demethylation on Foxp3 gene locus.

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    Ling Lu

    Full Text Available It has been documented all-trans retinoic acid (atRA promotes the development of TGF-β-induced CD4(+Foxp3(+ regulatory T cells (iTreg that play a vital role in the prevention of autoimmune responses, however, molecular mechanisms involved remain elusive. Our objective, therefore, was to determine how atRA promotes the differentiation of iTregs.Addition of atRA to naïve CD4(+CD25(- cells stimulated with anti-CD3/CD28 antibodies in the presence of TGF-β not only increased Foxp3(+ iTreg differentiation, but maintained Foxp3 expression through apoptosis inhibition. atRA/TGF-β-treated CD4(+ cells developed complete anergy and displayed increased suppressive activity. Infusion of atRA/TGF-β-treated CD4(+ cells resulted in the greater effects on suppressing symptoms and protecting the survival of chronic GVHD mice with typical lupus-like syndromes than did CD4(+ cells treated with TGF-β alone. atRA did not significantly affect the phosphorylation levels of Smad2/3 and still promoted iTreg differentiation in CD4(+ cells isolated from Smad3 KO and Smad2 conditional KO mice. Conversely, atRA markedly increased ERK1/2 activation, and blockade of ERK1/2 signaling completely abolished the enhanced effects of atRA on Foxp3 expression. Moreover, atRA significantly increased histone methylation and acetylation within the promoter and conserved non-coding DNA sequence (CNS elements at the Foxp3 gene locus and the recruitment of phosphor-RNA polymerase II, while DNA methylation in the CNS3 was not significantly altered.We have identified the cellular and molecular mechanism(s by which atRA promotes the development and maintenance of iTregs. These results will help to enhance the quantity and quality of development of iTregs and may provide novel insights into clinical cell therapy for patients with autoimmune diseases and those needing organ transplantation.

  3. Intensive chemotherapy for acute myeloid leukemia differentially affects circulating TC1, TH1, TH17 and TREG cells

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    Gjertsen Bjørn

    2010-07-01

    Full Text Available Abstract Background Several observations suggest that immunological events early after chemotherapy, possibly during the period of severe treatment-induced cytopenia, are important for antileukemic immune reactivity in acute myeloid leukemia (AML. We therefore investigated the frequencies of various T cell subsets (TC1, TH1, TH17 and CD25+ FoxP3+ TREG cells in AML patients with untreated disease and following intensive chemotherapy. Results Relative levels of circulating TC1 and TH1 cells were decreased in patients with severe chemotherapy-induced cytopenia, whereas TH17 levels did not differ from healthy controls. Increased levels of regulatory CD25+ FoxP3+ T cells were detected in AML patients with untreated disease, during chemotherapy-induced cytopenia and during regeneration after treatment. TH17 and TH1 levels were significantly higher in healthy males than females, but this gender difference was not detected during chemotherapy-induced cytopenia. Finally, exogenous IL17-A usually had no or only minor effects on proliferation of primary human AML cells. Conclusions We conclude that the effect of intensive AML chemotherapy differ between circulating T cell subsets, relative frequencies of TH17 cells are not affected by chemotherapy and this subset may affect AML cells indirectly through their immunoregulatory effects but probably not through direct effects of IL17-A.

  4. Interleukin-6 promotes systemic lupus erythematosus progression with Treg suppression approach in a murine systemic lupus erythematosus model.

    Science.gov (United States)

    Mao, Xiaoli; Wu, Yunyun; Diao, Huitian; Hao, Jianlei; Tian, Gaofei; Jia, Zhenghu; Li, Zheng; Xiong, Sidong; Wu, Zhenzhou; Wang, Puyue; Zhao, Liqing; Yin, Zhinan

    2014-11-01

    Our aim is to reveal the role of interleukin 6 (IL-6) in the pathogenesis of systemic lupus erythematosus (SLE) in a murine model of SLE. Normal female C57BL/6 mice were immunized with syngeneic-activated lymphocyte-derived DNA (ALD-DNA) to induce SLE. Non-immunized mice were used as control. SLE-associated markers, including anti-double-stranded DNA (anti-dsDNA) Abs, urine protein, and kidney histopathology, were assayed to ensure the induction of the disease. Compared with control mice, ALD-DNA immunized mice exhibited high levels of anti-dsDNA Abs, IL-6 expression in vivo and in vitro. We also found that IL-6 knockout (IL-6KO) mice were resistant to ALD-DNA-induced SLE. The activation of CD4(+) T cells in immunized IL-6KO mice was lower than in immunized wild-type (Wt) mice. Intracellular cytokine staining showed that Foxp3 expression in immunized IL-6KO mice was higher than in immunized Wt mice, which might be associated with the disease severity. We further discovered that ALD-DNA-stimulated dendritic cells supernatants could result in higher IL-6 and TNF-α expression and could suppress Foxp3 expression. In addition, blocking IL-6 could up-regulate Foxp3 expression. Therefore, our findings show that IL-6 promotes the progression of SLE via suppressing Treg differentiation.

  5. Dynamics of adrenal steroids are related to variations in Th1 and Treg populations during Mycobacterium tuberculosis infection in HIV positive persons.

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    Maria Florencia Quiroga

    Full Text Available Tuberculosis (TB remains the most frequent cause of illness and death from an infectious agent, and its interaction with HIV has devastating effects. We determined plasma levels of dehydroepiandrosterone (DHEA, its circulating form DHEA-suphate (DHEA-s and cortisol in different stages of M. tuberculosis infection, and explored their role on the Th1 and Treg populations during different scenarios of HIV-TB coinfection, including the immune reconstitution inflammatory syndrome (IRIS, a condition related to antiretroviral treatment. DHEA levels were diminished in HIV-TB and HIV-TB IRIS patients compared to healthy donors (HD, HIV+ individuals and HIV+ individuals with latent TB (HIV-LTB, whereas dehydroepiandrosterone sulfate (DHEA-s levels were markedly diminished in HIV-TB IRIS individuals. HIV-TB and IRIS patients presented a cortisol/DHEA ratio significantly higher than HIV+, HIV-LTB and HD individuals. A positive correlation was observed between DHEA-s and CD4 count among HIV-TB individuals. Conversely, cortisol plasma level inversely correlated with CD4 count within HIV-TB individuals. M. tuberculosis-specific Th1 lymphocyte count was increased after culturing PBMC from HIV-TB individuals in presence of DHEA. We observed an inverse correlation between DHEA-s plasma level and Treg frequency in co-infected individuals, and CD4+FoxP3+ Treg frequency was increased in HIV-TB and IRIS patients compared to other groups. Strikingly, we observed a prominent CD4+CD25-FoxP3+ population across HIV-TB and HIV-TB IRIS patients, which frequency correlated with DHEA plasma level. Finally, DHEA treatment negatively regulated FoxP3 expression without altering Treg frequency in co-infected patients. These data suggest an enhancing role for DHEA in the immune response against M. tuberculosis during HIV-TB coinfection and IRIS.

  6. Increased hepatic Th2 and Treg subsets are associated with biliary fibrosis in different strains of mice caused by Clonorchis sinensis.

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    Bei-Bei Zhang

    Full Text Available Previous studies showed that CD4+T cells responses might be involved in the process of biliary fibrosis. However, the underlying mechanism resulting in biliary fibrosis caused by Clonorchis sinensis remains not yet fully elucidated. The objectives of the present study were to investigate the different profiles of hepatic CD4+T cell subsets (Th1, Th2, Th17 and Treg cells and their possible roles in the biliary fibrosis of different strains of mice (C57BL/6, BALB/c and FVB mice induced by C. sinensis infection. C57BL/6, BALB/c and FVB mice were orally gavaged with 45 metacercariae. All mice were sacrificed on 28 days post infection in deep anesthesia conditions. The leukocytes in the liver were separated to examine CD4+T cell subsets by flow cytometry and the left lobe of liver was used to observe pathological changes, collagen depositions and the concentrations of hydroxyproline. The most serious cystic and fibrotic changes appeared in FVB infected mice indicated by gross observation, Masson's trichrome staining and hydroxyproline content detection. In contrast to C57BL/6 infected mice, diffuse nodules and more intensive fibrosis were observed in the BALB/c infected mice. No differences of the hepatic Th1 subset and Th17 subset were found among the three strains, but the hepatic Th2 and Treg cells and their relative cytokines were dramatically increased in the BALB/c and FVB infected groups compared with the C57BL/6 infected group (P<0.01. Importantly, increased Th2 subset and Treg subset all positively correlated with hydroxyproline contents (P<0.01. This result for the first time implied that the increased hepatic Th2 and Treg cell subsets were likely to play potential roles in the formation of biliary fibrosis in C. sinensis-infected mice.

  7. T Helper 17 Cells Interplay with CD4+CD25highFoxp3+ Tregs in Regulation of Inflammations and Autoimmune Diseases

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    Mai, Jietang; Wang, Hong; Yang#, Xiao-Feng

    2010-01-01

    Interleukin-17 (IL-17)-secreting T helper 17 cells (Th17) are a recently identified CD4+ T helper subset that has been implicated in various inflammatory and autoimmune diseases. Th17, along with CD4+CD25high Foxp3+ regulatory T cells (Tregs) and other newly emergent T helper subsets, Th9 and Tfh, have expanded the Th1-Th2 paradigm. Although this newly proposed six-subset paradigm significantly improved our understanding on the differentiation of CD4+ T helper cell subsets and the regulation of T helper cells in inflammation and autoimmunity, many questions remain to be answered. In this overview, we will briefly review the following issues: a) Old Th1-Th2 paradigm versus new multi-subset paradigm; b) Structural features of IL-17 family cytokines; c) Th17 cells; d) Effects of IL-17 on various cell types and tissues; e) IL-17 receptor and signaling pathways; f) Th17-mediated inflammations; and g) Protective mechanisms of IL-17 in infections. Lastly, we will look into the interaction of Th17 and Treg in autoimmune diseases and inflammation: Th17 cells interplay with Tregs. Regulation of autoimmunity and inflammation lies in the interplays of the different T helper subsets, therefore, better understanding of these subsets’ interactions with one another would greatly improve our approaches in developing therapy to combat inflammatory and autoimmune diseases. PMID:20515737

  8. Effects of excimer laser irradiation on the expression of Th17, Treg, TGF-beta1, and IL-6 in patients with psoriasis vulgaris

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    Xiong, Guo-Xin; Li, Xin-Zhong

    2017-11-01

    The effects of laser irradiation on the expression of T helper 17 (Th17) and regulatory T (Treg) cells and their related cytokines, transforming growth factor beta 1 (TGF-β1) and interleukin-6 (IL-6), respectively, in the peripheral blood of patients with psoriasis vulgaris were investigated. 38 patients with psoriasis vulgaris in the stable state were selected as the treatment group that was treated twice a week for eight weeks. Another 38 healthy persons were chosen as the control group. Before and after treatment, the percentages of Th17 cells and Treg cells in the patients’ peripheral blood were detected using flow cytometry, the content of TGF-β1 and IL-6 in the patients’ sera were detected using enzyme-linked immunosorbent assay, and the extent and severity of lesions were determined by weighing the psoriasis area and severity index (PASI). After laser treatment, the percentage of Th17 cells, the Th17/Treg cell ratio and the level of IL-6 in the peripheral blood of patients with psoriasis in the treatment group were significantly lower than those of the same patients before the treatment (P  psoriasis vulgaris was 84.21%, and the PASI score was significantly lower (P  psoriasis vulgaris.

  9. STAT3 Regulates Proliferation and Survival of CD8+ T Cells: Enhances Effector Responses to HSV-1 Infection, and Inhibits IL-10+ Regulatory CD8+ T Cells in Autoimmune Uveitis

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    Cheng-Rong Yu

    2013-01-01

    Full Text Available STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD. The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A, , , Bcl-2, OX-40, and upregulation of FasL, Bax, and Bad. We examined whether STAT3-deficient CD8+ T cells can mount effective response during herpes simplex virus (HSV-1 infection and experimental autoimmune uveitis (EAU. Compared to WT mice, HSV-1-infected STAT3-deficient mice (STAT3KO produced less IFN- and virus-specific KLRG-1+ CD8+ T cells. STAT3KO mice are also resistant to EAU and produced less IL-17-producing Tc17 cells. Resistance of STAT3KO to EAU correlated with marked expansion of IL-10-producing regulatory CD8+ T cells (CD8-Treg implicated in recovery from autoimmune encephalomyelitis. Thus, increases of IL-6-induced STAT3 activation observed during inflammation may inhibit expansion of CD8-Tregs, thereby impeding recovery from uveitis. These results suggest that STAT3 is a potential therapeutic target for upregulating CD8+ T cell-mediated responses to viruses and suggest the successful therapeutic targeting of STAT3 as treatment for uveitis, derived, in part, from promoting CD8-Treg expansion.

  10. Commensal oral bacteria antigens prime human dendritic cells to induce Th1, Th2 or Treg differentiation.

    Science.gov (United States)

    Kopitar, A N; Ihan Hren, N; Ihan, A

    2006-02-01

    In various immunopathologic conditions, bacterial flora induce an immune response which results in inflammatory manifestations, e.g. periapical granuloma. Dendritic cells provide the main orchestration of specific immune responses. The aim of our study was to test the capacity of distinct oral bacterial antigens (prepared from Streptococcus mitis, Propionibacterium acnes, and Bacteroides spp.) to prime human dendritic cells for stimulation of the T-lymphocyte response. To assess the T-lymphocyte response, the expression of CD25, CD69, intracellular interferon gamma (cIFN-gamma), and intracellular interleukin 4 (cIL-4) was determined. Dendritic cells were prepared from leukocyte buffy coat from healthy blood donors. Monocytes were stimulated with IL-4 and GM-CSF and dendritic cells activated with bacterial lysates. Cell suspensions contained up to 90% dendritic cells, which represented 2-12% of the initial number of mononuclear cells. Lymphocyte subsets that developed in lymphocyte cultures after 1 week of stimulation were analyzed by flow cytometry. Dendritic cells, primed with antigens of Bacteroides fragilis have shown significantly higher activation and expression of intercellular IFN-gamma by T lymphocytes compared to negative controls. The dendritic cells primed with antigens of P. acnes had no effect on T-lymphocyte activation or cytokine production; instead they induced differentiation of T lymphocytes into CD25bright cells (regulatory T cells) with a potentially inhibitory effect on immune response. Dendritic cells primed with antigens of S. mitis induced increased expression of cIL-4. We conclude that commensal oral bacteria antigens prepared from B. fragilis, S. mitis, and P. acnes prime human dendritic cells to induce Th1, Th2, and T(reg) differentiation, respectively. This may advance our understanding of immunopathologic manifestations in the oral cavity and offer new possibilities for redirecting immune responses in mucosal vaccination.

  11. A New Immunosuppressive Molecule Emodin Induces both CD4+FoxP3+ and CD8+CD122+ Regulatory T Cells and Suppresses Murine Allograft Rejection

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    Feifei Qiu

    2017-11-01

    Full Text Available Due to vigorous alloimmunity, an allograft is usually rejected without any conventional immunosuppressive treatment. However, continuous global immunosuppression may cause severe side effects, including tumors and infections. Mounting evidence has shown that cyclosporine (CsA, a common immunosuppressant used in clinic, impedes allograft tolerance by dampening regulatory T cells (Tregs, although it inhibits allograft rejection at the same time. Therefore, it is necessary to seek an alternative immunosuppressive drug that spares Tregs with high efficiency in suppression but low toxicity. In this study, we investigated the capacity of emodin, an anthraquinone molecule originally extracted from certain natural plants, to prolong transplant survival in a mouse model and explored the cellular and molecular mechanisms underlying its action. We found that emodin significantly extended skin allograft survival and hindered CD3+ T cell infiltration in the allograft, accompanied by an increase in CD4+Foxp3+ and CD8+CD122+ Treg frequencies and numbers but a reduction in effector CD8+CD44highCD62Llow T cells in recipient mice. Emodin also inhibited effector CD8+ T cells proliferation in vivo. However, CD4+CD25+, but not CD8+CD122+, Tregs derived from emodin-treated recipients were more potent in suppression of allograft rejection than those isolated from control recipients, suggesting that emodin also enhances the suppressive function of CD4+CD25+ Tregs. Interestingly, depleting CD25+ Tregs largely reversed skin allograft survival prolonged by emodin while depleting CD122+ Tregs only partially abrogated the same allograft survival. Furthermore, we found that emodin hindered dendritic cell (DC maturation and reduced alloantibody production posttransplantation. Finally, we demonstrated that emodin inhibited in vitro proliferation of T cells and blocked their mTOR signaling as well. Therefore, emodin may be a novel mTOR inhibitor that suppresses alloimmunity by

  12. Total glucosides of paeony ameliorates TNBS‑induced colitis by modulating differentiation of Th17/Treg cells and the secretion of cytokines.

    Science.gov (United States)

    Lin, Haihua; Zhang, Wenyou; Jiang, Xuepei; Chen, Renpin; Huang, Xielin; Huang, Zhiming

    2017-12-01

    The imbalance between effector CD4+ T helper 17 (Th17) and regulatory CD4+ T cells (Treg) cells and their associated cytokines, have been associated with the pathogenesis of inflammatory bowel disease (IBD). Total glycosides of paeony (TGP) is an alternative immunomodulatory agent that is widely used for the treatment of autoimmune diseases. The present study aimed to evaluate the modulatory effect of TGP in a rat model of colitis induced by 2,4,6‑trinitrobenzene sulfonic acid (TNBS). TGP was administered intragastrically 24 h after the TNBS intrarectal instillation for 7 days. TGP treatment ameliorated the clinical status and reversed the histopathologic severity of acute TNBS colitis. Furthermore, TGP inhibited the levels of Th17‑associated cytokines interleukin (IL)‑17, IL‑6, tumor necrosis factor‑α, whereas the expression levels of Treg‑associated cytokines IL‑10, transforming growth factor‑β in the plasma, colon, spleen and mesenteric lymph nodes (MLN). Additionally, TGP reduced the percentage of Th17 cells; however, the proportion of Treg cells in the spleen and MLN was increased. The present study also observed a suppression of Th17‑associated transcription factor, termed retinoid‑related orphan receptor‑γt (ROR‑γt). However, expression of the Treg‑associated transcription factor forkhead boxp3 was increased in the TGP treatment group. Therefore, the present findings suggest that TGP has a regulatory role in modulating the balance of Th17 and Treg cells to ameliorate the TNBS‑induced colitis and support the strategy of using TGP to treat IBD.

  13. Interplay of T Helper 17 Cells with CD4+CD25high FOXP3+ Tregs in Regulation of Allergic Asthma in Pediatric Patients

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    Amit Agarwal

    2014-01-01

    Full Text Available Background. There is evidence that Tregs are important to prevent allergic diseases like asthma but limited literature exists on role of TH17 cells in allergic diseases. Methods. Fifty children with asthma and respiratory allergy (study group and twenty healthy children (control group were recruited in this study. Total IgE levels and pulmonary function tests were assessed. The expression of Tregs and cytokines was determined by flow cytometry. Results. The average level of total IgE in study group (316.8 ± 189.8 IU/mL was significantly higher than controls (50 ± 17.5 IU/mL, P<0.0001. The frequency of TH17 cells and culture supernatant level of IL-17 in study group (12.09 ± 8.67 pg/mL was significantly higher than control group (2.01 ± 1.27 pg/mL, P<0.001. Alternatively, the frequency of FOXP3 level was significantly lower in study group [(49.00 ± 13.47%] than in control group [(95.91 ± 2.63%] and CD4+CD25+FOXP3+ to CD4+CD25+ ratio was also significantly decreased in study group [(6.33 ± 2.18%] compared to control group [(38.61 ± 11.04%]. The total serum IgE level is negatively correlated with FOXP3 level (r=-0.5273, P<0.0001. The FOXP3 expression is negatively correlated with the IL-17 levels (r=-0.5631, P<0.0001 and IL-4 levels (r=-0.2836, P=0.0460. Conclusions. Imbalance in TH17/Tregs, elevated IL-17, and IL-4 response and downregulation of FOXP3 were associated with allergic asthma.

  14. Anti-IL-2 treatment impairs the expansion of T(reg cell population during acute malaria and enhances the Th1 cell response at the chronic disease.

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    Cláudia A Zago

    Full Text Available Plasmodium chabaudi infection induces a rapid and intense splenic CD4(+ T cell response that contributes to both disease pathogenesis and the control of acute parasitemia. The subsequent development of clinical immunity to disease occurs concomitantly with the persistence of low levels of chronic parasitemia. The suppressive activity of regulatory T (T(reg cells has been implicated in both development of clinical immunity and parasite persistence. To evaluate whether IL-2 is required to induce and to sustain the suppressive activity of T(reg cells in malaria, we examined in detail the effects of anti-IL-2 treatment with JES6-1 monoclonal antibody (mAb on the splenic CD4(+ T cell response during acute and chronic P. chabaudi AS infection in C57BL/6 mice. JES6-1 treatment on days 0, 2 and 4 of infection partially inhibits the expansion of the CD4(+CD25(+Foxp3(+ cell population during acute malaria. Despite the concomitant secretion of IL-2 and expression of high affinity IL-2 receptor by large CD4(+ T cells, JES6-1 treatment does not impair effector CD4(+ T cell activation and IFN-γ production. However, at the chronic phase of the disease, an enhancement of cellular and humoral responses occurs in JES6-1-treated mice, with increased production of TNF-α and parasite-specific IgG2a antibodies. Furthermore, JES6-1 mAb completely blocked the in vitro proliferation of CD4(+ T cells from non-treated chronic mice, while it further increased the response of CD4(+ T cells from JES6-1-treated chronic mice. We conclude that JES6-1 treatment impairs the expansion of T(reg cell population during early P. chabaudi malaria and enhances the Th1 cell response in the late phase of the disease.

  15. Expression of selected genes of dendritic and Treg cells in blood and skin of morphea patients treated with UVA1 phototherapy

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    Osmola-Mańkowska, Agnieszka J.; Kowalczyk, Michał J.; Żaba, Ryszard W.; Adamski, Zygmunt; Dańczak-Pazdrowska, Aleksandra

    2018-01-01

    Introduction Morphea is a chronic autoimmune disease characterized by fibrosis of the skin. Dendritic cells (DC) and regulatory T cells (Tregs) play a significant role in development of autoimmune and tolerance mechanisms. The aim of the study was to establish the expression of selected genes of plasmacytoid and myeloid DC, Treg cells, and the microenvironment of cytokines (interleukin-17A (IL-17A), transforming growth factor β (TGF-β)) in blood and skin of morphea patients. In addition, the effect of UVA1 phototherapy on expression of the aforementioned genes was evaluated. Material and methods The study was performed on 15 blood and 10 skin samples from patients with morphea. The evaluation included expression of CLEC4C (C-type lectin domain family 4, member C receptor), Lymphocyte antigen 75 (LY75), Forkhead box p3 (foxp3) transcription factor, IL-17A and TGF-β genes in peripheral blood mononuclear cells (PBMC) and in skin samples both before and after UVA1 phototherapy using real-time polymerase chain reaction. Results The study revealed lower expression of CLEC4C before (p = 0.010) and after (p = 0.009) phototherapy and lower expression of IL-17A before (p = 0.038) phototherapy in PBMC of patients with morphea vs. the control group. Expression of CLEC4C in PBMC correlated negatively (rho = –0.90; p = 0.001) with activity of disease after phototherapy. No significant differences were found between expression of analysed genes before and after UVA1 therapy in PBMC and skin of morphea patients. Conclusions The results do not confirm the involvement of analysed subsets of DC and Tregs in UVA1 phototherapy in morphea, but point to CLEC4C as a possible biomarker associated with the disease activity. PMID:29593811

  16. Bone marrow CD11b(+)F4/80(+) dendritic cells ameliorate collagen-induced arthritis through modulating the balance between Treg and Th17.

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    Zhang, Lingling; Fu, Jingjing; Sheng, Kangliang; Li, Ying; Song, Shanshan; Li, Peipei; Song, Shasha; Wang, Qingtong; Chen, Jingyu; Yu, Jianhua; Wei, Wei

    2015-03-01

    Tolerogenic dendritic cells (DCs) are well-known to show an immunosuppressive function. In this study we determine the therapeutic effects and potential mechanisms of transferred bone marrow (BM) CD11b(+)F4/80(+) DCs on collagen-induced arthritis (CIA) in mice. Murine BM CD11b(+)F4/80(+) DCs were generated under the stimulation of GM-CSF and IL-4, and the function of BM CD11b(+) F4/80(+) DCs was identified by measuring the levels of IL-10, TGF-beta and indoleamine 2,3-dioxygenase (IDO). BM CD11b(+)F4/80(+) DCs were transferred to CIA mice by intravenous injections. The histopathology of joint and spleen were evaluated. T lymphocyte proliferation, Treg and Th17 subsets were analyzed. The expressions of Foxp3, Helios and RORγt in T lymphocytes co-cultured with BM CD11b(+)F4/80(+) DCs were measured in vitro. We found that BM CD11b(+)F4/80(+) DCs induced by GM-CSF and IL-4 could express high levels of IL-10, TGF-beta and IDO. BM CD11b(+)F4/80(+) DCs significantly reduced the pathologic scores in joints and spleens, which correlated significantly with the reduced T lymphocyte proliferation and Th17 cell number, and with the increased Tregs number. In vitro, OVA-pulsed BM CD11b(+)F4/80(+) DCs promoted Treg cell expansion, enhanced IL-10 and CTLA-4 protein expression, augmented Foxp3 and Helios mRNA expression, and inhibited RORγt and IL-17 mRNA expression. Taken together, BM CD11b(+)F4/80(+) DCs are able to ameliorate the development and severity of CIA, at least partly by inducing Foxp3(+) Treg cell expansion and suppressing Th17 function. The BM CD11b(+)F4/80(+) DCs might have a promising immunotherapeutic potential for autoimmune arthritis. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Role of Fas and Treg Cells in Fracture Healing as Characterized in the Fas-Deficient (lpr) Mouse Model of Lupus†

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    Al-Sebaei, Maisa O; Daukss, Dana M; Belkina, Anna C; Kakar, Sanjeev; Wigner, Nathan A; Cusher, Daniel; Graves, Dana; Einhorn, Thomas; Morgan, Elise; Gerstenfeld, Louis C

    2014-01-01

    Previous studies showed that loss of tumor necrosis factor α (TNFα) signaling delayed fracture healing by delaying chondrocyte apoptosis and cartilage resorption. Mechanistic studies showed that TNFα induced Fas expression within chondrocytes; however, the degree to which chondrocyte apoptosis is mediated by TNFα alone or dependent on the induction of Fas is unclear. This question was addressed by assessing fracture healing in Fas-deficient B6.MRL/Faslpr/J mice. Loss of Fas delayed cartilage resorption but also lowered bone fraction in the calluses. The reduced bone fraction was related to elevated rates of coupled bone turnover in the B6.MRL/Faslpr/J calluses, as evidenced by higher osteoclast numbers and increased osteogenesis. Analysis of the apoptotic marker caspase 3 showed fewer positive chondrocytes and osteoclasts in calluses of B6.MRL/Faslpr/J mice. To determine if an active autoimmune state contributed to increased bone turnover, the levels of activated T cells and Treg cells were assessed. B6.MRL/Faslpr/J mice had elevated Treg cells in both spleens and bones of B6.MRL/Faslpr/J but decreased percentage of activated T cells in bone tissues. Fracture led to ∼30% to 60% systemic increase in Treg cells in both wild-type and B6.MRL/Faslpr/J bone tissues during the period of cartilage formation and resorption but either decreased (wild type) or left unchanged (B6.MRL/Faslpr/J) the numbers of activated T cells in bone. These results show that an active autoimmune state is inhibited during the period of cartilage resorption and suggest that iTreg cells play a functional role in this process. These data show that loss of Fas activity specifically in chondrocytes prolonged the life span of chondrocytes and that Fas synergized with TNFα signaling to mediate chondrocyte apoptosis. Conversely, loss of Fas systemically led to increased osteoclast numbers during later periods of fracture healing and increased osteogenesis. These findings suggest that retention

  18. Role of Fas and Treg cells in fracture healing as characterized in the fas-deficient (lpr) mouse model of lupus.

    Science.gov (United States)

    Al-Sebaei, Maisa O; Daukss, Dana M; Belkina, Anna C; Kakar, Sanjeev; Wigner, Nathan A; Cusher, Daniel; Graves, Dana; Einhorn, Thomas; Morgan, Elise; Gerstenfeld, Louis C

    2014-06-01

    Previous studies showed that loss of tumor necrosis factor α (TNFα) signaling delayed fracture healing by delaying chondrocyte apoptosis and cartilage resorption. Mechanistic studies showed that TNFα induced Fas expression within chondrocytes; however, the degree to which chondrocyte apoptosis is mediated by TNFα alone or dependent on the induction of Fas is unclear. This question was addressed by assessing fracture healing in Fas-deficient B6.MRL/Fas(lpr) /J mice. Loss of Fas delayed cartilage resorption but also lowered bone fraction in the calluses. The reduced bone fraction was related to elevated rates of coupled bone turnover in the B6.MRL/Fas(lpr) /J calluses, as evidenced by higher osteoclast numbers and increased osteogenesis. Analysis of the apoptotic marker caspase 3 showed fewer positive chondrocytes and osteoclasts in calluses of B6.MRL/Fas(lpr) /J mice. To determine if an active autoimmune state contributed to increased bone turnover, the levels of activated T cells and Treg cells were assessed. B6.MRL/Fas(lpr) /J mice had elevated Treg cells in both spleens and bones of B6.MRL/Fas(lpr) /J but decreased percentage of activated T cells in bone tissues. Fracture led to ∼30% to 60% systemic increase in Treg cells in both wild-type and B6.MRL/Fas(lpr) /J bone tissues during the period of cartilage formation and resorption but either decreased (wild type) or left unchanged (B6.MRL/Fas(lpr) /J) the numbers of activated T cells in bone. These results show that an active autoimmune state is inhibited during the period of cartilage resorption and suggest that iTreg cells play a functional role in this process. These data show that loss of Fas activity specifically in chondrocytes prolonged the life span of chondrocytes and that Fas synergized with TNFα signaling to mediate chondrocyte apoptosis. Conversely, loss of Fas systemically led to increased osteoclast numbers during later periods of fracture healing and increased osteogenesis. These findings

  19. An alphavirus vector overcomes the presence of neutralizing antibodies and elevated numbers of Tregs to induce immune responses in humans with advanced cancer.

    Science.gov (United States)

    Morse, Michael A; Hobeika, Amy C; Osada, Takuya; Berglund, Peter; Hubby, Bolyn; Negri, Sarah; Niedzwiecki, Donna; Devi, Gayathri R; Burnett, Bruce K; Clay, Timothy M; Smith, Jonathan; Lyerly, H Kim

    2010-09-01

    Therapeutic anticancer vaccines are designed to boost patients' immune responses to tumors. One approach is to use a viral vector to deliver antigen to in situ DCs, which then activate tumor-specific T cell and antibody responses. However, vector-specific neutralizing antibodies and suppressive cell populations such as Tregs remain great challenges to the efficacy of this approach. We report here that an alphavirus vector, packaged in virus-like replicon particles (VRP) and capable of efficiently infecting DCs, could be repeatedly administered to patients with metastatic cancer expressing the tumor antigen carcinoembryonic antigen (CEA) and that it overcame high titers of neutralizing antibodies and elevated Treg levels to induce clinically relevant CEA-specific T cell and antibody responses. The CEA-specific antibodies mediated antibody-dependent cellular cytotoxicity against tumor cells from human colorectal cancer metastases. In addition, patients with CEA-specific T cell responses exhibited longer overall survival. These data suggest that VRP-based vectors can overcome the presence of neutralizing antibodies to break tolerance to self antigen and may be clinically useful for immunotherapy in the setting of tumor-induced immunosuppression.

  20. [Effects and mechanism of Angelicae Sinensis Radix on Th1/Th2 and Th17/Treg in mice with asthma and Yin deficiency syndrome].

    Science.gov (United States)

    Ma, Ting-Ting; Feng, Xing-Zhong; Wang, Xue-Yan

    2017-02-01

    Angelicae Sinensis Radix, with nourishing Yin, promoting blood circulation, and moisturizing dryness functions, is commonly used in clinical medicine. In order to investigate the effects and mechanism of Angelica sinensis(AS) on Th1/Th2 and Th17/Treg in mice with asthma and Yin deficiency syndrome, asthmatic and Yin deficiency syndrome Balb/c mice models were established by injecting and inhaling ovalbumin(OVA) and thyroxin. The models were treated with dexamethasone(DXM), AS extract and AS extract+DXM, respectively. Pathological examination of lung tissues was conducted by HE staining, and ELISA was used to detect the levels of IL-4, IL-17, IFN-γ, TGF-β as well as retinoic acid receptor-related orphan receptor (RORγt). Results showed that AS could significantly improve the situation of inflammation infiltration, increase ratios of IFN-γ/IL-4 and TGF-β/IL-17, decrease the levels of RORγt in lung tissues. The AS+DXM group showed a best treatment effect. The results indicated that AS played a therapeutic role for asthma with Yin deficiency syndrome and improved airway inflammation by inhibiting the expression of RORγt in lung tissues and regulating the balance of Th1/Th2 and Th17/Treg. Copyright© by the Chinese Pharmaceutical Association.

  1. Simultaneous analysis of multiple T helper subsets in leprosy reveals distinct patterns of Th1, Th2, Th17 and Tregs markers expression in clinical forms and reactional events.

    Science.gov (United States)

    Azevedo, Michelle de Campos Soriani; Marques, Heloisa; Binelli, Larissa Sarri; Malange, Mariana Silva Vieira; Devides, Amanda Carreira; Silva, Eliane Aparecida; Fachin, Luciana Raquel Vincenzi; Ghidella, Cassio Cesar; Soares, Cleverson Teixeira; Garlet, Gustavo Pompermaier; Rosa, Patrícia Sammarco; Belone, Andrea de Farias Fernandes; Trombone, Ana Paula Favaro

    2017-12-01

    Leprosy is a chronic infectious disease caused by Mycobacterium leprae. Previous studies have demonstrated that the difference among clinical forms of leprosy can be associated with the immune response of patients, mainly by T helper (Th) and regulatory T cells (Tregs). Then, aiming at clarifying the immune response, the expression of cytokines related to Th1, Th2, Th17 and Tregs profiles were evaluated by qPCR in 87 skin biopsies from leprosy patients. Additionally, cytokines and anti-PGL-1 antibodies were determined in serum by ELISA. The results showed that the expression of various targets (mRNA) related to Th1, Th2, Th17 and Tregs were significantly modulated in leprosy when compared with healthy individuals, suggesting the presence of a mixed profile. In addition, the targets related to Th1 predominated in the tuberculoid pole and side and Th2 and Tregs predominated in the lepromatous pole and side; however, Th17 targets showed a mixed profile. Concerning reactional events, Tregs markers were decreased and IL-15 was increased in reversal reaction and IL-17F, CCL20 and IL-8 in erythema nodosum leprosum, when compared with the respective non-reactional leprosy patients. Additionally, ELISA analysis demonstrated that IL-22, IL-6, IL-10 and anti-PGL-1 antibody levels were significantly higher in the serum of patients when compared with healthy individuals, and IL-10 and anti-PGL-1 antibodies were also increased in the lepromatous pole and side. Together, these results indicate that Th1, Th2 and Th17 are involved in the determination of clinical forms of leprosy and suggest that decreased Tregs activity may be involved in the pathogenesis of reactional events.

  2. Increased hepatic Th2 and Treg subsets are associated with biliary fibrosis in different strains of mice caused by Clonorchis sinensis

    Science.gov (United States)

    Fang, Fan; Du, Ying; Ma, Rui; Li, Xiang-Yang; Yu, Qian; Meng, Di; Tang, Ren-Xian; Zheng, Kui-Yang

    2017-01-01

    Previous studies showed that CD4+T cells responses might be involved in the process of biliary fibrosis. However, the underlying mechanism resulting in biliary fibrosis caused by Clonorchis sinensis remains not yet fully elucidated. The objectives of the present study were to investigate the different profiles of hepatic CD4+T cell subsets (Th1, Th2, Th17 and Treg cells) and their possible roles in the biliary fibrosis of different strains of mice (C57BL/6, BALB/c and FVB mice) induced by C. sinensis infection. C57BL/6, BALB/c and FVB mice were orally gavaged with 45 metacercariae. All mice were sacrificed on 28 days post infection in deep anesthesia conditions. The leukocytes in the liver were separated to examine CD4+T cell subsets by flow cytometry and the left lobe of liver was used to observe pathological changes, collagen depositions and the concentrations of hydroxyproline. The most serious cystic and fibrotic changes appeared in FVB infected mice indicated by gross observation, Masson’s trichrome staining and hydroxyproline content detection. In contrast to C57BL/6 infected mice, diffuse nodules and more intensive fibrosis were observed in the BALB/c infected mice. No differences of the hepatic Th1 subset and Th17 subset were found among the three strains, but the hepatic Th2 and Treg cells and their relative cytokines were dramatically increased in the BALB/c and FVB infected groups compared with the C57BL/6 infected group (Psinensis-infected mice. PMID:28151995

  3. Tumor necrosis factor alpha blockade exacerbates murine psoriasis-like disease by enhancing Th17 function and decreasing expansion of Treg cells.

    Science.gov (United States)

    Ma, Hak-Ling; Napierata, Lee; Stedman, Nancy; Benoit, Stephen; Collins, Mary; Nickerson-Nutter, Cheryl; Young, Deborah A

    2010-02-01

    Patients with psoriasis and psoriatic arthritis respond well to tumor necrosis factor alpha (TNFalpha) blockers in general; however, there is now mounting evidence that a small cohort of patients with rheumatoid arthritis who receive TNFalpha blockers develop psoriasis. This study was undertaken to explore the mechanisms underlying TNFalpha blockade-induced exacerbation of skin inflammation in murine psoriasis-like skin disease. Skin inflammation was induced in BALB/c scid/scid mice after they received CD4+CD45RB(high)CD25- (naive CD4) T cells from donor mice. These mice were treated with either anti-interleukin-12 (anti-IL-12)/23p40 antibody or murine TNFRII-Fc fusion protein and were examined for signs of disease, including histologic features, various cytokine levels in the serum, and cytokine or FoxP3 transcripts in the affected skin and draining lymph node (LN) cells. In a separate study, naive CD4+ T cells were differentiated into Th1 or Th17 lineages with anti-CD3/28 magnetic beads and appropriate cytokines in the presence or absence of TNFalpha. Cytokine gene expression from these differentiated cells was also determined. Neutralization of TNFalpha exacerbated skin inflammation and markedly enhanced the expression of the proinflammatory cytokines IL-1beta, IL-6, IL-17, IL-21, and IL-22 but suppressed FoxP3 expression in the skin and reduced the number of FoxP3-positive Treg cells in the draining LNs. TNFalpha also demonstrated a divergent role during priming and reactivation of naive T cells. These results reveal a novel immunoregulatory role of TNFalpha on Th17 and Treg cells in some individuals, which may account for the exacerbation of skin inflammation in some patients who receive anti-TNF treatments.

  4. Recombinant ESAT-6-CFP10 Fusion Protein Induction of Th1/Th2 Cytokines and FoxP3 Expressing Treg Cells in Pulmonary TB.

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    Dolly Jackson-Sillah

    Full Text Available Early secretory antigenic target 6 (ESAT-6 and culture filtrate protein 10 (CFP-10 are Mycobacterium tuberculosis (Mtb-specific antigens that are secreted by actively metabolising bacteria and contribute to the virulence of the bacteria. Their ability to induce Treg and Th2 responses, particularly during the first two weeks of treatment, has not been comprehensively examined to date. The purpose of this work was to characterise Th1, Th2 and Treg responses to rESAT-6-CFP10 fusion protein in TB patients before and during the intensive phase of treatment and in healthy M.bovis BCG vaccinated donors.Forty-six newly diagnosed, HIV-negative, smear-positive pulmonary TB patients and 20 healthy donors were recruited in the UK and Ghana. Their peripheral blood mononuclear cells (PBMC were used in ex vivo ELISPOT and in vitro cultures to identify immunological parameters of interest.The study confirmed that protective immune responses to rESAT-6-CFP10 are impaired in active TB but improved during treatment: circulating antigen-specific IL-4-producing T-cells were increased in untreated TB but declined by two weeks of treatment while the circulating antigen-specific IFN-γ producing T cells which showed a transient rise at one week of treatment, persisted at baseline levels at two months of treatment. In vitro T cell proliferation and IFN-γ production were reduced, while IL-4 and CD4(+FoxP3(+CD25(hi cell expression were increased in response to rESAT-6-CFP10 fusion protein in untreated TB. These responses were reversed during early treatment of TB.These observations support further investigations into the possible utility of these parameters as markers of active disease and favourable treatment outcomes.

  5. Recombinant ESAT-6-CFP10 Fusion Protein Induction of Th1/Th2 Cytokines and FoxP3 Expressing Treg Cells in Pulmonary TB.

    Science.gov (United States)

    Jackson-Sillah, Dolly; Cliff, Jacqueline M; Mensah, Gloria Ivy; Dickson, Emmanuel; Sowah, Sandra; Tetteh, John K A; Addo, Kwasi K; Ottenhoff, Tom H M; Bothamley, Graham; Dockrell, Hazel M

    2013-01-01

    Early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) are Mycobacterium tuberculosis (Mtb)-specific antigens that are secreted by actively metabolising bacteria and contribute to the virulence of the bacteria. Their ability to induce Treg and Th2 responses, particularly during the first two weeks of treatment, has not been comprehensively examined to date. The purpose of this work was to characterise Th1, Th2 and Treg responses to rESAT-6-CFP10 fusion protein in TB patients before and during the intensive phase of treatment and in healthy M.bovis BCG vaccinated donors. Forty-six newly diagnosed, HIV-negative, smear-positive pulmonary TB patients and 20 healthy donors were recruited in the UK and Ghana. Their peripheral blood mononuclear cells (PBMC) were used in ex vivo ELISPOT and in vitro cultures to identify immunological parameters of interest. The study confirmed that protective immune responses to rESAT-6-CFP10 are impaired in active TB but improved during treatment: circulating antigen-specific IL-4-producing T-cells were increased in untreated TB but declined by two weeks of treatment while the circulating antigen-specific IFN-γ producing T cells which showed a transient rise at one week of treatment, persisted at baseline levels at two months of treatment. In vitro T cell proliferation and IFN-γ production were reduced, while IL-4 and CD4(+)FoxP3(+)CD25(hi) cell expression were increased in response to rESAT-6-CFP10 fusion protein in untreated TB. These responses were reversed during early treatment of TB. These observations support further investigations into the possible utility of these parameters as markers of active disease and favourable treatment outcomes.

  6. Characterization of CD4 and CD8 T Cell Responses in MuSK Myasthenia Gravis

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    Yi, JS; Guidon, A; Sparks, S; Osborne, R; Juel, VC; Massey, JM; Sanders, DB; Weinhold, KJ; Guptill, JT

    2014-01-01

    Muscle specific tyrosine kinase myasthenia gravis (MuSK MG) is a form of autoimmune MG that predominantly affects women and has unique clinical features, including prominent bulbar weakness, muscle atrophy, and excellent response to therapeutic plasma exchange. Patients with MuSK MG have predominantly IgG4 autoantibodies directed against MuSK on the postsynaptic muscle membrane. Lymphocyte functionality has not been reported in this condition. The goal of this study was to characterize T-cell responses in patients with MuSK MG. Intracellular production of IFN-gamma, TNF-alpha, IL-2, IL-17, and IL-21 by CD4+ and CD8+ T-cells was measured by polychromatic flow cytometry in peripheral blood samples from 11 Musk MG patients and 10 healthy controls. Only one MuSK MG patient was not receiving immunosuppressive therapy. Regulatory T-cells (Treg) were also included in our analysis to determine if changes in T cell function were due to altered Treg frequencies. CD8+ T-cells from MuSK MG patients had higher frequencies of polyfunctional responses than controls, and CD4+ T-cells had higher IL-2, TNF-alpha, and IL-17. MuSK MG patients had a higher percentage of CD4+ T-cells producing combinations of IFN-gamma/IL-2/TNF-gamma, TNF-alpha/IL-2, and IFN-gamma/TNF-alpha. Interestingly, Treg numbers and CD39 expression were not different from control values. MuSK MG patients had increased frequencies of Th1 and Th17 cytokines and were primed for polyfunctional proinflammatory responses that cannot be explained by a defect in Treg function or number. PMID:24378287

  7. La depleción de las células T regulatorias aumenta el número de las células CD8 durante la infección con el virus del tumor mamario murino Regulatory T cell depletion increases the number of CD8 cells during mouse mammary tumor virus infection

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    Gabriel Cabrera

    2011-06-01

    Full Text Available El virus del tumor mamario murino (MMTV es un retrovirus que se transmite durante la lactancia y que ha desarrollado estrategias para explotar y subvertir el sistema inmune. En un modelo de infección natural con MMTV hemos mostrado previamente que la infección causa incrementos tempranos y progresivos de células T regulatorias (Treg CD4+CD25+Foxp3+ específicas para el superantígeno (Sag viral en las placas de Peyer (PP. En este trabajo se evaluó si la depleción de las células Treg influencia la población de células CD8+ durante la infección con MMTV a través del amamantamiento. La depleción de las células Treg al día 6 de infección causó incrementos en el porcentaje y número absoluto de las células CD8+ en los ganglios y provocó un incremento en la intensidad de fluorescencia media del marcador de activación CD44 en esas células. Los incrementos en el número absoluto de las células CD8 se observaron en células con cadenas variables Vβ del receptor de las células T (TCR tanto reactivas como no reactivas al Sag. Previamente habíamos demostrado que la depleción de las células Treg al día 6 de infección disminuye la carga viral. Los resultados presentados en este trabajo sugieren que, al menos a partir del día 6 de infección con MMTV, las células Treg podrían tener un rol inhibiendo la generación de una respuesta CD8 antiviral.Mouse mammary tumor virus (MMTV is a milk-borne betaretrovirus that has developed strategies to exploit and subvert the host immune system. We have shown in a natural model of MMTV infection that the virus causes early and progressive increases in superantigen (Sag-specific CD4+ CD25+ Foxp3+ regulatory T cells (Treg in Peyer's patches. Herein, we evaluated whether the depletion of Treg cells affects the CD8+ population during milk-borne MMTV infection. At day 6 of infection, the depletion of Treg cells increased the percentage and absolute number of CD8+ cells in lymph nodes as well as the

  8. Deep Surveying of the Transcriptional and Alternative Splicing Signatures for Decidual CD8+ T Cells at the First Trimester of Human Healthy Pregnancy

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    Weihong Zeng

    2018-05-01

    Full Text Available Decidual CD8+ (dCD8 T cells have been proposed to play important roles in immune protection against the invading pathogens and in tolerance toward the growing semi-allogeneic fetus during early pregnancy. However, their phenotypic and functional characteristics remain poorly defined. Here, we performed the first analysis of the transcriptional and alternative splicing (AS signatures for human first-trimester dCD8 T cells using high-throughput mRNA sequencing. Our data revealed that dCD8 T cells have distinct transcriptional and AS landscapes when compared with their autologous peripheral blood CD8+ (pCD8 T counterparts. Furthermore, human dCD8 T cells were observed to contain CD8-Treg and effector-memory T-cell subsets, and display enhanced functionality in terms of degranulation and cytokine production on a per-cell basis. Additionally, we have identified the novel splice junctions that use a high ratio of the non-canonical splicing motif GC-AG and found that AS is not a major contributor to the gene expression-level changes between paired pCD8 and dCD8 T cells. Together, our findings not only provide a comprehensive framework of the transcriptional and AS landscapes but also reveal the functional feature of human dCD8 T cells, which are of great importance in understanding the biology of these cells and the physiology of human healthy pregnancy.

  9. CD8+ T cells provide immune protection against murine disseminated endotheliotropic Orientia tsutsugamushi infection.

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    Guang Xu

    2017-07-01

    Full Text Available Scrub typhus, caused by a Gram-negative obligately intracellular coccobacillus, Orientia tsutsugamushi, is a long neglected but important tropical disease. Orientia tsutsugamushi causes illness in one million people each year, and 1 billion people are at risk. Without appropriate diagnosis and treatment, the disease can cause severe multiorgan failure with a case fatality rate of 7-15%. The current gaps in knowledge of immunity include the unknown mechanisms of host immunity to O. tsutsugamushi. Using an intravenous (i.v. disseminated infection mouse model, we observed that more CD8+ T cells than CD4+ T cells were present in the spleen of infected mice at 12 dpi. We also determined that Treg cells and the proportion of T cells producing IL-10 were significantly increased from 6 dpi, which correlated with the onset of illness, body weight loss, and increased bacterial loads. We further studied CD8-/-, MHC I-/- and wild type control (WT C57BL/6J mice to determine the importance of CD8+ T cells and MHC I molecules. After infection with an ordinarily sub-lethal dose of O. tsutsugamushi, all CD8-/- and MHC I-/- mice were moribund between 12 and 15 dpi, whereas all WT mice survived. Bacterial loads in the lung, kidney, liver and spleen of CD8-/- and MHC I-/- mice were significantly greater than those in WT mice. Interferon-γ (IFN-γ and granzyme B mRNA levels in the liver of CD8-/- and MHC I-/- mice were significantly greater than in WT mice. In addition, more severe histopathologic lesions were observed in CD8-/- mice. Finally, adoptive transfer confirmed a major role of immune CD8+ T cells as well as a less effective contribution by immune CD8 T cell-depleted splenocytes in protection against O. tsutsugamushi infection. These studies demonstrated the critical importance of CD8+ T cells in the host immune response during O. tsutsugamushi infection.

  10. Treatment to sustain a Th17-type phenotype to prevent skewing toward Treg and to limit premalignant lesion progression to cancer.

    Science.gov (United States)

    Young, M Rita I; Levingston, Corinne A; Johnson, Sara D

    2016-05-15

    While immune suppression is a hallmark of head and neck squamous cell carcinoma (HSNCC), the immunological impact of premalignant oral lesions, which often precedes development of HNSCC, is unknown. The present study assessed the changes in splenic and draining lymph node CD4(+) cell populations and their production of select cytokines that occur in mice with carcinogen-induced premalignant oral lesions and the changes that occur as lesions progress to oral cancer. These studies found skewing toward Th1 and Th17-type phenotypes in the spleen and lymph nodes of mice with premalignant oral lesions and a shift to Treg as lesions progress to cancer. Since the role of Th17 cells in the progression from premalignant lesions to cancer is not clear, studies determined the immunological and clinical effect of treating mice bearing premalignant oral lesions with a TGF-β type 1 receptor inhibitor plus IL-23 as an approach to sustain the Th17 phenotype. These studies showed that the treatment approach not only sustained the Th17 phenotype, but also increased distal spleen cell and regional lymph node cell production of other stimulatory/inflammatory mediators and slowed premalignant lesion progression to cancer. © 2016 UICC.

  11. Orally-Induced Intestinal CD4+ CD25+ FoxP3+ Treg Controlled Undesired Responses towards Oral Antigens and Effectively Dampened Food Allergic Reactions.

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    Paola Lorena Smaldini

    Full Text Available The induction of peripheral tolerance may constitute a disease-modifying treatment for allergic patients. We studied how oral immunotherapy (OIT with milk proteins controlled allergy in sensitized mice (cholera toxin plus milk proteins upon exposure to the allergen. Symptoms were alleviated, skin test was negativized, serum specific IgE and IgG1 were abrogated, a substantial reduction in the secretion of IL-5 and IL-13 by antigen-stimulated spleen cells was observed, while IL-13 gene expression in jejunum was down-regulated, and IL-10 and TGF-β were increased. In addition, we observed an induction of CD4+CD25+FoxP3+ cells and IL-10- and TGF-β-producing regulatory T cells in the lamina propria. Finally, transfer experiments confirmed the central role of these cells in tolerance induction. We demonstrated that the oral administration of milk proteins pre- or post-sensitization controlled the Th2-immune response through the elicitation of mucosal IL-10- and TGF-β-producing Tregs that inhibited hypersensitivity symptoms and the allergic response.

  12. Desequilíbrio imunológico periférico mediado por células Th17/Treg em pacientes com rinite alérgica

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    Xuekun Huang

    2014-04-01

    Full Text Available Introdução: A rinite alérgica (RA é uma doença não infecciosa da mucosa nasal mediada por IgE após o contato com alérgenos. Objetivo: Investigar as células Th17 periféricas e CD4 + CD25 + Foxp3 + células T reguladoras (Treg e a expressão sérica de citocinas em pacientes com RA. Métodos: De março a maio de 2012, foi coletado o sangue periférico de 14 pacientes com RA (grupo RA e seis indivíduos saudáveis (grupo controle. A detecção das células Th17 e células Treg foi realizada através da citometria de fluxo e os níveis séricos de IL -17 e TGF- β1. Foram medidos por ELISA. Resultados: A percentagem de células Th17 no grupo RA foi bem maior do que no grupo controle (p < 0,01. A proporção de células Treg no grupo RA também foi drasticamente menor quando comparada ao grupo controle (p < 0,01. No grupo RA, o nível sérico de IL-17 foi significativamente maior do que no grupo controle (p < 0,01. Conclusão: O desequilíbrio de células Th17/Treg periféricas desempenha um papel importante na patogênese da RA.

  13. High Levels of IL-10 and CD4+CD25hi+ Treg Cells in Endemic Burkitt’s Lymphoma Patients

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    Godfred Futagbi

    2015-08-01

    Full Text Available Background: The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt’s Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt’s Lymphoma (eBL. This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. Methods: T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. Results: CD4+ and CD8+ cells in age- and sex-matched healthy controls (n = 3 expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL patients (n = 4. In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower (p = 0.004 while IL-10 was significantly higher (p = 0.038, in eBL patients (n = 21 compared to controls (n = 16. Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria (n = 26 and eBL (n = 14 patients compared to healthy controls (n = 19; p = 0.000 and p = 0.027, respectively. Conclusion: The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells.

  14. High Levels of IL-10 and CD4+CD25hi+ Treg Cells in Endemic Burkitt’s Lymphoma Patients

    Science.gov (United States)

    Futagbi, Godfred; Gyan, Ben; Nunoo, Harriet; Tetteh, John K.A.; Welbeck, Jennifer E.; Renner, Lorna Awo; Ofori, Michael; Dodoo, Daniel; Edoh, Dominic A.; Akanmori, Bartholomew D.

    2015-01-01

    Background: The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt’s Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt’s Lymphoma (eBL). This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. Methods: T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. Results: CD4+ and CD8+ cells in age- and sex-matched healthy controls (n = 3) expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL) patients (n = 4). In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower (p = 0.004) while IL-10 was significantly higher (p = 0.038), in eBL patients (n = 21) compared to controls (n = 16). Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria (n = 26) and eBL (n = 14) patients compared to healthy controls (n = 19; p = 0.000 and p = 0.027, respectively). Conclusion: The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells. PMID:28536409

  15. High Levels of IL-10 and CD4+CD25hi+ Treg Cells in Endemic Burkitt's Lymphoma Patients.

    Science.gov (United States)

    Futagbi, Godfred; Gyan, Ben; Nunoo, Harriet; Tetteh, John K A; Welbeck, Jennifer E; Renner, Lorna Awo; Ofori, Michael; Dodoo, Daniel; Edoh, Dominic A; Akanmori, Bartholomew D

    2015-08-04

    The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt's Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt's Lymphoma (eBL). This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. CD4+ and CD8+ cells in age- and sex-matched healthy controls ( n = 3) expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL) patients ( n = 4). In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower ( p = 0.004) while IL-10 was significantly higher ( p = 0.038), in eBL patients ( n = 21) compared to controls ( n = 16). Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria ( n = 26) and eBL ( n = 14) patients compared to healthy controls ( n = 19; p = 0.000 and p = 0.027, respectively). The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells.

  16. Effect of Lactobacillus salivarius on Th1/Th2 cytokines and the number of spleen CD4⁺ CD25⁺ Foxp3⁺ Treg in asthma Balb/c mouse.

    Science.gov (United States)

    Yun, Xiang; Shang, Yunxiao; Li, Miao

    2015-01-01

    Bronchial asthma is a chronic airway inflammatory disease that involves T lymphocytes. In order to explore the effect of Lactobacillus salivarius on Th1/Th2 cytokines and the number of spleen CD4(+) CD25(+) Foxp3(+) Treg in asthma Balb/c mouse, we constructed acute asthma model with ovalbumin to observe the mouse behavior change in Balb/c mice. The expression of GATA-3 mRNA and T-bet mRNA was measured by real-time PCR. The proportion of CD4(+) CD25(+) Foxp3(+) Treg/CD4(+) was determined by flow cytometry. The results demonstrated that oral gavage with Lactobacillus salivarius before sensitization could alleviate the clinical symptoms, airway hyper-reactivity and airway inflammation in asthma mouse to some extent; Lactobacillus salivarius may improve the imbalance of Th1/Th2 in asthma mouse through increasing the expression of T-bet mRNA at the transcriptional level and inhibiting the expression of GATA-3 mRNA simultaneously. CD4(+) CD25(+) Foxp3(+) Treg cells may be involved in the pathogenesis of bronchial asthma, and may be the upstream regulatory mechanism of the improvement of Th1/Th2 imbalance by Lactobacillus salivarius.

  17. Squamous cell carcinomas escape immune surveillance via inducing chronic activation and exhaustion of CD8+ T Cells co-expressing PD-1 and LAG-3 inhibitory receptors.

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    Mishra, Ameet K; Kadoishi, Tanya; Wang, Xiaoguang; Driver, Emily; Chen, Zhangguo; Wang, Xiao-Jing; Wang, Jing H

    2016-12-06

    Squamous cell carcinoma (SCC) is the second commonest type of skin cancer. Moreover, about 90% of head and neck cancers are SCCs. SCCs develop at a significantly higher rate under chronic immunosuppressive conditions, implicating a role of immune surveillance in controlling SCCs. It remains largely unknown how SCCs evade immune recognition. Here, we established a mouse model by injecting tumor cells derived from primary SCCs harboring KrasG12D mutation and Smad4 deletion into wild-type (wt) or CD8-/- recipients. We found comparable tumor growth between wt and CD8-/- recipients, indicating a complete escape of CD8+ T cell-mediated anti-tumor responses by these SCCs. Mechanistically, CD8+ T cells apparently were not defective in infiltrating tumors given their relatively increased percentage among tumor infiltrating lymphocytes (TILs). CD8+ TILs exhibited phenotypes of chronic activation and exhaustion, including overexpression of activation markers, co-expression of programmed cell death 1 (PD-1) and lymphocyte activation gene-3 (LAG-3), as well as TCRβ downregulation. Among CD4+ TILs, T regulatory cells (Tregs) were preferentially expanded. Contradictory to prior findings in melanoma, Treg expansion was independent of CD8+ T cells in our SCC model. Unexpectedly, CD8+ T cells were required for promoting NK cell infiltration within SCCs. Furthermore, we uncovered AKT-dependent lymphocyte-induced PD-L1 upregulation on SCCs, which was contributed greatly by combinatorial effects of CD8+ T and NK cells. Lastly, dual blockade of PD-1 and LAG-3 inhibited the tumor growth of SCCs. Thus, our findings identify novel immune evasion mechanisms of SCCs and suggest that immunosuppressive mechanisms operate in a cancer-type specific and context-dependent manner.

  18. In vitro induction of functional allergen-specific CD4+ CD25high Treg cells in horses affected with insect bite hypersensitivity.

    Science.gov (United States)

    Hamza, E; Akdis, C A; Wagner, B; Steinbach, F; Marti, E

    2013-08-01

    proliferation of CD4(+) CD25(-) cells in an antigen-specific manner. The in vitro induction of functional allergen-specific Treg cells in IBH-affected horses suggests a potential therapeutic use of these cells in allergy. © 2013 John Wiley & Sons Ltd.

  19. (99) Tc-methylene diphosphonate improves rheumatoid arthritis disease activity by increasing the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs.

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    Su, Dinglei; Shen, Minning; Gu, Bingjie; Wang, Xiaoqin; Wang, Dandan; Li, Xia; Sun, Lingyun

    2016-06-01

    γδ T cells exhibit important functions in the pathogenesis of rheumatoid arthritis (RA). In recent years, numerous studies harnessed the γδ T cell-activating capacity of aminobiphosphonates for the treatment of malignant tumors. As (99) Tc-methylene diphosphonate ((99) Tc-MDP) has long been widely used for the treatment of RA in China with good efficacy, we are interested in whether this drug exerts its therapeutic effect on RA by modulating peripheral γδ T cells of RA patients. To investigate the effect of (99) Tc-MDP on the frequency of γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs in the peripheral blood of patients with active RA. Nineteen patients with active RA were treated with (99) Tc-MDP intravenously at a dose of 20 μg/day consecutively for 10-14 days. Before and after treatment, the main clinical and laboratory parameters for each patient were evaluated. The frequency of CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs was detected by flow cytometry. Serum levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 and transforming growth factor (TGF)-β were measured with enzyme-linked immunosorbent assay. After intravenous (99) Tc-MDP therapy, the frequency of peripheral CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs were significantly elevated, paralleled with decreased serum levels of TNF-α and IL-6 and increased level of serum TGF-β. The elevation of peripheral CD3(+) γδ(+) T cells was positively correlated with increased serum TGF-β and decreased disease activity. (99) Tc-MDP may improve the activity of RA through upregulating the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs as well as affecting the serum cytokine environment by increasing TGF-β and decreasing TNF-α and IL-6. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  20. CD4CD8αα lymphocytes, a novel human regulatory T cell subset induced by colonic bacteria and deficient in patients with inflammatory bowel disease.

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    Guillaume Sarrabayrouse

    2014-04-01

    Full Text Available How the microbiota affects health and disease is a crucial question. In mice, gut Clostridium bacteria are potent inducers of colonic interleukin (IL-10-producing Foxp3 regulatory T cells (Treg, which play key roles in the prevention of colitis and in systemic immunity. In humans, although gut microbiota dysbiosis is associated with immune disorders, the underlying mechanism remains unknown. In contrast with mice, the contribution of Foxp3 Treg in colitis prevention has been questioned, suggesting that other compensatory regulatory cells or mechanisms may exist. Here we addressed the regulatory role of the CD4CD8 T cells whose presence had been reported in the intestinal mucosa and blood. Using colonic lamina propria lymphocytes (LPL and peripheral blood lymphocytes (PBL from healthy individuals, and those with colon cancer and irritable bowel disease (IBD, we demonstrated that CD4CD8αα (DP8α T lymphocytes expressed most of the regulatory markers and functions of Foxp3 Treg and secreted IL-10. Strikingly, DP8α LPL and PBL exhibited a highly skewed repertoire toward the recognition of Faecalibacterium prausnitzii, a major Clostridium species of the human gut microbiota, which is decreased in patients with IBD. Furthermore, the frequencies of DP8α PBL and colonic LPL were lower in patients with IBD than in healthy donors and in the healthy mucosa of patients with colon cancer, respectively. Moreover, PBL and LPL from most patients with active IBD failed to respond to F. prausnitzii in contrast to PBL and LPL from patients in remission and/or healthy donors. These data (i uncover a Clostridium-specific IL-10-secreting Treg subset present in the human colonic LP and blood, (ii identify F. prausnitzii as a major inducer of these Treg, (iii argue that these cells contribute to the control or prevention of colitis, opening new diagnostic and therapeutic strategies for IBD, and (iv provide new tools to address the systemic impact of both these Treg

  1. Distribution of CD4(pos) -, CD8(pos) - and regulatory T cells in the upper and lower gastrointestinal tract in healthy young subjects.

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    Tauschmann, Martin; Prietl, Barbara; Treiber, Gerlies; Gorkiewicz, Gregor; Kump, Patrizia; Högenauer, Christoph; Pieber, Thomas R

    2013-01-01

    The gastrointestinal immune system is involved in the development of several autoimmune-mediated diseases, including inflammatory bowel disease, multiple sclerosis, and type 1 diabetes mellitus. Alterations in T-cell populations, especially regulatory T cells (Tregs), are often evident in patients suffering from these diseases. To be able to detect changes in T-cell populations in diseased tissue, it is crucial to investigate T-cell populations in healthy individuals, and to characterize their variation among different regions of the gastrointestinal (GI) tract. While limited data exist, quantitative data on biopsies systematically drawn from various regions of the GI tract are lacking, particularly in healthy young humans. In this report, we present the first systematic assessment of how T cells--including Tregs--are distributed in the gastrointestinal mucosa throughout the GI tract of healthy young humans by means of multi-parameter FACS analysis. Gastroduodenoscopy and colonoscopy were performed on 16 healthy volunteers aged between 18 and 32. Biopsies were drawn from seven GI regions, and were used to determine the frequencies of CD8(+)-, CD4(+)- and Tregs in the gastrointestinal mucosa by means of multi-parameter FACS analysis. Our data show that there is significant variation in the baseline T-cell landscape along the healthy human gastrointestinal tract, and that mucosal T-cell analyses from a single region should not be taken as representative of the entire gastrointestinal tract. We show that certain T-cell subsets in the gastrointestinal mucosa vary significantly among regions; most notably, that Tregs are enriched in the appendiceal orifice region and the ascending colon, and that CD8(pos) T cells are enriched in the gastric mucosa.

  2. Suppression of HIV replication by CD8+regulatory T-cells in elite controllers

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    Wei eLu

    2016-04-01

    Full Text Available We previously demonstrated in the Chinese macaque model that an oral vaccine made of inactivated SIV and lactobacillus plantarum induced CD8+regulatory T-cells which suppressed the activation of SIV+CD4+T-cells, prevented SIV replication and protected macaques from SIV challenges.Here ,we sought whether a similar population of CD8+T-regs would induce the suppression of HIV replication in elite controllers (ECs, a small population (3‰ of HIV-infected patients with undetectable HIV replication. For that purpose, we investigated the in vitro antiviral activity of fresh CD8+T-cells on HIV-infected CD4+T-cells taken from 10 ECs. The 10 ECs had a classical genomic profile: all of them carried the KIR3DL1 gene and nine carried at least one allele of HLA-B:Bw4-80Ile ( i.e. with an isoleucine residue at position 80. In the nine HLA-B:Bw4-80Ile positive patients, we demonstrated a strong viral suppression byKIR3DL1-expressing CD8+T-cells that required cell-to-cell contact to switch off the activation signals in infected CD4+T-cells. KIR3DL1-expressing CD8+T-cells withdrawal and KIR3DL1 neutralization by a specific anti-KIR antibody inhibited the suppression of viral replication. Our findings provide the first evidence for an instrumental role of KIR-expressing CD8+ regulatory T- cells in the natural control of HIV-1 infection.

  3. Regulatory T cells participation in the infection immunopathogenesis by the Human Immunodeficiency Virus (HIV-1 Participação de células T regulatórias (Tregs na imunopatogênese da infecção pelo vírus da imunodeficiência humana 1 (HIV-1

    Directory of Open Access Journals (Sweden)

    Isabele Kazahaya Borges

    2010-12-01

    Full Text Available The survival of patients infected with human immunodeficiency virus (HIV-1 is related to the prevention and effective treatment of opportunistic infections. It is known that the main parameters to evaluate the progression of disease caused by HIV-1 is the counting of CD4 + T cells and viral load of HIV-1. Regulatory T cells has been considered the focus of intense research within the immune system as well as in the pathogenesis of several diseases. Natural regulatory T cells (Tregs CD4+CD25+ act in the modulation of immune activation, functioning as critical mediators of immune homeostasis and self-tolerance. Furthermore, recent studies has shown that the function of Tregs cells is not limited to the prevention of autoimmunity, but is also important to control all forms of immune responses in the context of inflammation, infection, allergy, transplantation and tumor immunity. Many authors have identified Tregs as beneficial effector cells in the context of AIDS, but other researchers disagree. Tregs can exert an important role in the immunopathology of HIV infection due to the suppressor activity on cellular activation and effector function. Thus, this review discusses the molecular and immunological aspects of Tregs in the HIV system. A sobrevivência de pacientes infectados pelo vírus da imunodeficiência humana (HIV-1 é relacionada à prevenção e ao tratamento eficaz de infecções oportunistas. É conhecido que os principais parâmetros para avaliar a progressão da doença causada pelo HIV-1 são contagem de células T CD4+ e carga viral do HIV-1. Células T regulatórias têm sido foco de intensas investigações dentro do sistema imunológico como também na patogênese de diversas doenças. Sabe-se que as células T reguladoras (Tregs CD4+CD25+FoxP3+ atuam na modulação da ativação imune, funcionando como mediadores críticos da homeostasia imune e da auto-tolerância. Além disso, recentes estudos têm demonstrado que as c

  4. La depleción de las células T regulatorias aumenta el número de las células CD8 durante la infección con el virus del tumor mamario murino

    Directory of Open Access Journals (Sweden)

    Gabriel Cabrera

    2011-06-01

    Full Text Available El virus del tumor mamario murino (MMTV es un retrovirus que se transmite durante la lactancia y que ha desarrollado estrategias para explotar y subvertir el sistema inmune. En un modelo de infección natural con MMTV hemos mostrado previamente que la infección causa incrementos tempranos y progresivos de células T regulatorias (Treg CD4+CD25+Foxp3+ específicas para el superantígeno (Sag viral en las placas de Peyer (PP. En este trabajo se evaluó si la depleción de las células Treg influencia la población de células CD8+ durante la infección con MMTV a través del amamantamiento. La depleción de las células Treg al día 6 de infección causó incrementos en el porcentaje y número absoluto de las células CD8+ en los ganglios y provocó un incremento en la intensidad de fluorescencia media del marcador de activación CD44 en esas células. Los incrementos en el número absoluto de las células CD8 se observaron en células con cadenas variables Vβ del receptor de las células T (TCR tanto reactivas como no reactivas al Sag. Previamente habíamos demostrado que la depleción de las células Treg al día 6 de infección disminuye la carga viral. Los resultados presentados en este trabajo sugieren que, al menos a partir del día 6 de infección con MMTV, las células Treg podrían tener un rol inhibiendo la generación de una respuesta CD8 antiviral.

  5. CD8+ T Cells Contribute to the Development of Coronary Arteritis in the Lactobacillus casei Cell Wall Extract-Induced Murine Model of Kawasaki Disease.

    Science.gov (United States)

    Noval Rivas, Magali; Lee, Youngho; Wakita, Daiko; Chiba, Norika; Dagvadorj, Jargalsaikhan; Shimada, Kenichi; Chen, Shuang; Fishbein, Michael C; Lehman, Thomas J A; Crother, Timothy R; Arditi, Moshe

    2017-02-01

    Kawasaki disease (KD) is the leading cause of acquired heart disease among children in developed countries. Coronary lesions in KD in humans are characterized by an increased presence of infiltrating CD3+ T cells; however, the specific contributions of the different T cell subpopulations in coronary arteritis development remain unknown. Therefore, we sought to investigate the function of CD4+ and CD8+ T cells, Treg cells, and natural killer (NK) T cells in the pathogenesis of KD. We addressed the function of T cell subsets in KD development by using a well-established murine model of Lactobacillus casei cell wall extract (LCWE)-induced KD vasculitis. We determined which T cell subsets were required for development of KD vasculitis by using several knockout murine strains and depleting monoclonal antibodies. LCWE-injected mice developed coronary lesions characterized by the presence of inflammatory cell infiltrates. Frequently, this chronic inflammation resulted in complete occlusion of the coronary arteries due to luminal myofibroblast proliferation (LMP) as well as the development of coronary arteritis and aortitis. We found that CD8+ T cells, but not CD4+ T cells, NK T cells, or Treg cells, were required for development of KD vasculitis. The LCWE-induced murine model of KD vasculitis mimics many histologic features of the disease in humans, such as the presence of CD8+ T cells and LMP in coronary artery lesions as well as epicardial coronary arteritis. Moreover, CD8+ T cells functionally contribute to the development of KD vasculitis in this murine model. Therapeutic strategies targeting infiltrating CD8+ T cells might be useful in the management of KD in humans. © 2016, American College of Rheumatology.

  6. Human papilloma virus load and PD-1/PD-L1, CD8+ and FOXP3 in anal cancer patients treated with chemoradiotherapy: Rationale for immunotherapy

    Science.gov (United States)

    Balermpas, Panagiotis; Martin, Daniel; Wieland, Ulrike; Rave-Fränk, Margret; Strebhardt, Klaus; Rödel, Claus; Fokas, Emmanouil; Rödel, Franz

    2017-01-01

    ABSTRACT We examined the prognostic role of immune markers programmed cell death protein-1 (PD-1) and its ligand (PD-L1), CD8+ tumor-infiltrating lymphocytes (TILs), FOXP3+ Tregs and phosphorylated Caspase-8 (T273) in patients with anal squamous cell cancer (ASCC) treated with standard chemoradiotherapy (CRT). The baseline immunohistochemical expression of immune markers was correlated with clinicopathologic characteristics, and cumulative incidence of local failure, disease-free survival (DFS) and overall survival (OS) in 150 patients, also in the context of human papilloma virus 16 (HPV16) DNA load and p16INK4a expression. After a median follow-up of 40 mo (1–205 mo), the 5-y cumulative incidence of local failure and DFS was 19.4% and 67.2%, respectively. Strong immune marker expression was significantly more common in tumors with high HPV16 viral load. In multivariant analysis, high CD8+ and PD-1+ TILs expression predicted for improved local control (p = 0.023 and p = 0.007, respectively) and DFS (p = 0.020 and p = 0.014, respectively). Also, high p16INK4a (p = 0.011) and PD-L1 (p = 0.033) expression predicted for better local control, whereas high FOXP3+ Tregs (p = 0.050) and phosphorylated Caspase-8 (p = 0.031) expression correlated with superior DFS. Female sex and high HPV16 viral load correlated with favorable outcome for all three clinical endpoints. The present data provide, for the first time, robust explanation for the favorable clinical outcome of HPV16-positive ASCC patients harboring strong immune cell infiltration. Our findings are relevant for treatment stratification with immune PD-1/PD-L1 checkpoint inhibitors to complement CRT and should be explored in a clinical trial. PMID:28405521

  7. Altering the balance between immune activation versus regulation in the skin to promote CD8+ T-cell activity within epithelial cancers

    DEFF Research Database (Denmark)

    Bridge, Jennifer A.; Overgaard, Nana Haahr; Steptoe, Raymond

    . The expression, in a mouse model (“E7”), of the HPV16 E7 gene in keratinocytes under the control of the K14 promoter, leads to a local immune suppressive environment, as evidenced by the lack of graft rejection when E7 skin grafts are placed on WT recipient mice. Furthermore, well healed (>30 days) E7 skin...... did not reject. As in the WT mice however, rejection could be induced through the coadministration of an anti-CD4 antibody. The data suggest that the removal of a CD4+, non T-reg cell, leads to CD8+ T-cell activity in the skin as evidenced by E7 skin graft destruction....... grafts are not rejected when mice are immunised with E7 peptide in combination with Quil A- or CASAC-based adjuvants. This is despite a substantial increase in E7 peptide/H-2Db pentamer staining in the blood, and marked killing of E7-peptide expressing TC-1 cells when injected i.v., confirming that CD8 T...

  8. Myeloablative temozolomide enhances CD8⁺ T-cell responses to vaccine and is required for efficacy against brain tumors in mice.

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    Luis A Sanchez-Perez

    Full Text Available Temozolomide (TMZ is an alkylating agent shown to prolong survival in patients with high grade glioma and is routinely used to treat melanoma brain metastases. A prominent side effect of TMZ is induction of profound lymphopenia, which some suggest may be incompatible with immunotherapy. Conversely, it has been proposed that recovery from chemotherapy-induced lymphopenia may actually be exploited to potentiate T-cell responses. Here, we report the first demonstration of TMZ as an immune host-conditioning regimen in an experimental model of brain tumor and examine its impact on antitumor efficacy of a well-characterized peptide vaccine. Our results show that high-dose, myeloablative (MA TMZ resulted in markedly reduced CD4(+, CD8(+ T-cell and CD4(+Foxp3(+ TReg counts. Adoptive transfer of naïve CD8(+ T cells and vaccination in this setting led to an approximately 70-fold expansion of antigen-specific CD8(+ T cells over controls. Ex vivo analysis of effector functions revealed significantly enhanced levels of pro-inflammatory cytokine secretion from mice receiving MA TMZ when compared to those treated with a lower lymphodepletive, non-myeloablative (NMA dose. Importantly, MA TMZ, but not NMA TMZ was uniquely associated with an elevation of endogenous IL-2 serum levels, which we also show was required for optimal T-cell expansion. Accordingly, in a murine model of established intracerebral tumor, vaccination-induced immunity in the setting of MA TMZ-but not lymphodepletive, NMA TMZ-led to significantly prolonged survival. Overall, these results may be used to leverage the side-effects of a clinically-approved chemotherapy and should be considered in future study design of immune-based treatments for brain tumors.

  9. Asymptomatic memory CD8+ T cells

    Science.gov (United States)

    Khan, Arif Azam; Srivastava, Ruchi; Lopes, Patricia Prado; Wang, Christine; Pham, Thanh T; Cochrane, Justin; Thai, Nhi Thi Uyen; Gutierrez, Lucas; BenMohamed, Lbachir

    2014-01-01

    Generation and maintenance of high quantity and quality memory CD8+ T cells determine the level of protection from viral, bacterial, and parasitic re-infections, and hence constitutes a primary goal for T cell epitope-based human vaccines and immunotherapeutics. Phenotypically and functionally characterizing memory CD8+ T cells that provide protection against herpes simplex virus type 1 and type 2 (HSV-1 and HSV-2) infections, which cause blinding ocular herpes, genital herpes, and oro-facial herpes, is critical for better vaccine design. We have recently categorized 2 new major sub-populations of memory symptomatic and asymptomatic CD8+ T cells based on their phenotype, protective vs. pathogenic function, and anatomical locations. In this report we are discussing a new direction in developing T cell-based human herpes vaccines and immunotherapeutics based on the emerging new concept of “symptomatic and asymptomatic memory CD8+ T cells.” PMID:24499824

  10. A viral long terminal repeat expressed in CD4+CD8+ precursors is downregulated in mature peripheral CD4-CD8+ or CD4+CD8- T cells.

    OpenAIRE

    Paquette, Y; Doyon, L; Laperrière, A; Hanna, Z; Ball, J; Sekaly, R P; Jolicoeur, P

    1992-01-01

    The long terminal repeat from a thymotropic mouse mammary tumor virus variant, DMBA-LV, was used to drive the expression of two reporter genes, murine c-myc and human CD4, in transgenic mice. Expression was observed specifically in thymic immature cells. Expression of c-myc in these cells induced oligoclonal CD4+ CD8+ T-cell thymomas. Expression of human CD4 was restricted to thymic progenitor CD4- CD8- and CD4+ CD8+ T cells and was shut off in mature CD4+ CD8- and CD4- CD8+ T cells, known to...

  11. Korelasi Kadar Feritin dengan Jumlah CD4, CD8, dan Rasio CD4/CD8 pada Penyandang Talasemia Mayor Anak

    Directory of Open Access Journals (Sweden)

    Bonnie Arseno

    2017-11-01

    Hasil. Didapatkan jumlah CD4 absolut, CD4%, CD8 absolut dan rasio CD4/CD8 menurun. Selain itu, terdapat jumlah CD4 absolut, CD8 absolut dan CD8% meningkat. Pada kelompok usia ≤5 tahun, korelasi kadar feritin dengan CD8 absolut, CD8%, dan rasio CD4/CD8 berturut-turut menghasilkan koefisien korelasi 0,691, 0,557, -0,680, dan p<0,05. Sementara pada kelompok lama terapi ≤5 tahun korelasi kadar feritin dengan CD8 absolut, CD8%, dan rasio CD4/CD8 menghasilkan koefisien korelasi 0,709, 0,571, -0,726 dengan p<0,05. Kesimpulan. Tidak terdapat korelasi antara kadar feritin dengan jumlah CD4, CD8, rasio CD4/CD8. Peningkatan kadar feritin akan diikuti dengan peningkatan jumlah CD8 absolut dan CD8%, serta penurunan rasio CD4/CD8 pada penyandang talasemia mayor anak berdasar atas usia dan lama terapi ≤5 tahun.

  12. NF-κB RelA renders tumor-associated macrophages resistant to and capable of directly suppressing CD8+ T cells for tumor promotion.

    Science.gov (United States)

    Li, Liwen; Han, Lei; Sun, Fan; Zhou, Jingjiao; Ohaegbulam, Kim C; Tang, Xudong; Zang, Xingxing; Steinbrecher, Kris A; Qu, Zhaoxia; Xiao, Gutian

    2018-01-01

    Activation of the inflammatory transcription factor NF-κB in tumor-associated macrophages (TAMs) is assumed to contribute to tumor promotion. However, whether and how NF-κB drives the antitumor macrophages to become pro-tumorigenic have not been determined in any cancer type yet. Similarly, how TAMs repress CD8 + cytotoxic T lymphocytes (CTLs) remains largely unknown, although their importance in regulatory T (Treg) cell regulation and tumor promotion has been well appreciated. Here, using an endogenous lung cancer model we uncover a direct crosstalk between TAMs and CTLs. TAMs suppress CTLs through the T-cell inhibitory molecule B7x (B7-H4/B7S1) in a cell-cell contact manner, whereas CTLs kill TAMs in a tumor antigen-specific manner. Remarkably, TAMs secrete the known T-cell suppressive cytokine interleukin-10 (IL-10) to activate, but not to repress, CTLs. Notably, one major role of cell-intrinsic NF-κB RelA is to drive TAMs to suppress CTLs for tumor promotion. It induces B7x expression in TAMs directly, and restricts IL-10 expression indirectly by repressing expression of the NF-κB cofactor Bcl3 and subsequent Bcl3/NF-κB1-mediated transcription of IL-10. It also renders TAMs resistant to CTLs by up-regulating anti-apoptotic genes. These studies help understand how immunity is shaped in lung tumorigenesis, and suggest a RelA-targeted immunotherapy for this deadliest cancer.

  13. Comparative immune phenotypic analysis of cutaneous Squamous Cell Carcinoma and Intraepidermal Carcinoma in immune-competent individuals: proportional representation of CD8+ T-cells but not FoxP3+ Regulatory T-cells is associated with disease stage.

    Directory of Open Access Journals (Sweden)

    Andrew Freeman

    Full Text Available Squamous Cell Carcinoma (SCC is a type of non-melanoma skin cancer prevalent in immune-suppressed transplant recipients and older individuals with a history of chronic sun-exposure. SCC itself is believed to be a late-stage manifestation that can develop from premalignant lesions including Intraepidermal Carcinoma (IEC. Notably, while SCC regression is rare, IEC typically regresses in response to immune modifying topical treatments, however the underlying immunological reasons for these differential responses remain unclear. This study aimed to define whether IEC and SCC are associated with distinct immune profiles. We investigated the immune cell infiltrate of photo-damaged skin, IEC, and SCC tissue using 10-colour flow cytometry following fresh lesion digest. We found that IEC lesions contain higher percentages of CD3+ T-cells than photo-damaged skin, however, the abundance of CD3-CD56+ Natural Killer (NK cells, CD11c+HLA-DR+ conventional Dendritic Cells (cDC, BDCA-2+HLA-DR+ plasmacytoid DC (pDC, FoxP3+ Regulatory T-cells (T-reg, Vα24+Vβ11+ invariant NKT-cells, and γδ Tcells did not alter with disease stage. Within the total T-cell population, high percentages of CD4+ T-cells were associated with SCC, yet CD8+ T-cells were less abundant in SCC compared with IEC. Our study demonstrates that while IEC lesions contain a higher proportion of T-cells than SCC lesions in general, SCC lesions specifically display a lower abundance of CD8+ T-cells than IEC. We propose that differences in CD8+ T-cell abundance contribute critically to the different capacity of SCC and IEC to regress in response to immune modifying topical treatments. Our study also suggests that a high ratio of CD4+ T-cells to CD8+ T-cells may be a immunological diagnostic indicator of late-stage SCC development in immune-competent patients.

  14. CD8+ T cells in inflammatory demyelinating disease

    DEFF Research Database (Denmark)

    Weiss, Hanne A; Millward, Jason M; Owens, Trevor

    2007-01-01

    We review the contribution made by CD8+ T cells to inflammation in the central nervous system (CNS) in Multiple Sclerosis (MS), and discuss their role in the animal model Experimental Autoimmune Encephalomyelitis (EAE). We show that the inflammatory cytokines interferon-gamma and interleukin-17...... are differentially regulated in CNS-infiltrating CD4+ and CD8+ T cells in EAE, and that CD8+ T cells regulate disease. In MS, CD8+ T cells appear to play a role in promotion of disease, so cytokine regulation is likely different in CD8+ T cells in MS and EAE...

  15. CD4+/CD8+ double-positive T cells

    DEFF Research Database (Denmark)

    Overgaard, Nana H; Jung, Ji-Won; Steptoe, Raymond J

    2015-01-01

    CD4(+)/CD8(+) DP thymocytes are a well-described T cell developmental stage within the thymus. However, once differentiated, the CD4(+) lineage or the CD8(+) lineage is generally considered to be fixed. Nevertheless, mature CD4(+)/CD8(+) DP T cells have been described in the blood and peripheral...... cells, CD4(+)/CD8(+) T cell populations, outside of the thymus, have recently been described to express concurrently ThPOK and Runx3. Considerable heterogeneity exists within the CD4(+)/CD8(+) DP T cell pool, and the function of CD4(+)/CD8(+) T cell populations remains controversial, with conflicting...... reports describing cytotoxic or suppressive roles for these cells. In this review, we describe how transcriptional regulation, lineage of origin, heterogeneity of CD4 and CD8 expression, age, species, and specific disease settings influence the functionality of this rarely studied T cell population....

  16. CD8αα expression marks terminally differentiated human CD8+ T cells expanded in chronic viral infection

    Directory of Open Access Journals (Sweden)

    Lucy Jane Walker

    2013-08-01

    Full Text Available The T cell co-receptor CD8αβ enhances T cell sensitivity to antigen, however studies indicate CD8αα has the converse effect and acts as a co-repressor. Using a combination of Thymic Leukaemia antigen (TL tetramer, which directly binds CD8αα, anti-CD161 and anti-Vα7.2 antibodies we have been able for the first time to clearly define CD8αα expression on human CD8 T cells subsets. In healthy controls CD8αα is most highly expressed by CD161 bright (CD161++ mucosal associated invariant T (MAIT cells, with CD8αα expression highly restricted to the TCR Vα7.2+ cells of this subset. We also identified CD8αα-expressing populations within the CD161 mid (CD161+ and negative (CD161- non-MAIT CD8 T cell subsets and show TL-tetramer binding to correlate with expression of CD8β at low levels in the context of maintained CD8α expression (CD8α+CD8βlow. In addition, we found CD161-CD8α+CD8βlow populations to be significantly expanded in the peripheral blood of HIV-1 and hepatitis B (mean of 47% and 40% of CD161- T cells respectively infected individuals. Such CD8αα expressing T cells are an effector-memory population (CD45RA-, CCR7-, CD62L- that express markers of activation and maturation (HLA-DR+, CD28-, CD27-, CD57+ and are functionally distinct, expressing greater levels of TNF-α and IFN-γ on stimulation and perforin at rest than their CD8α+CD8βhigh counterparts. Antigen-specific T cells in HLA-B*4201+HIV-1 infected patients are found within both the CD161-CD8α+CD8βhigh and CD161-CD8α+CD8βlow populations. Overall we have clearly defined CD8αα expressing human T cell subsets using the TL-tetramer, and have demonstrated CD161-CD8α+CD8βlow populations, highly expanded in disease settings, to co-express CD8αβ and CD8αα. Co-expression of CD8αα on CD8αβ T cells may impact on their overall function in-vivo and contribute to the distinctive phenotype of highly differentiated populations in HBV and HIV-1 infection.

  17. Characterization of primary cutaneous CD8+/CD30+ lymphoproliferative disorders.

    Science.gov (United States)

    Martires, Kathryn J; Ra, Seong; Abdulla, Farah; Cassarino, David S

    2015-11-01

    CD30 primary cutaneous lymphoproliferative diseases include both lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large cell lymphoma (PCALCL). The neoplastic cell of most primary CD30 lymphoproliferative disorders is CD4 positive. The terminology LyP "type D" has been used to describe a growing number of cases of LyP with a predominantly CD8 infiltrate. PCALCL with a CD8 phenotype has also been described, which presents a particularly difficult diagnostic and management challenge, given the difficulty in distinguishing it histologically from other cytotoxic lymphomas such as primary cutaneous aggressive epidermotropic CD8 cytotoxic T-cell lymphoma and CD8 gamma/delta and natural killer/T-cell lymphoma. We report 7 additional cases of these rare cutaneous CD8/CD30 lymphoproliferative disorders. We also present a unique case of CD8/CD30 LyP with histologic similarities to LyP type B. In all 7 of our cases of CD8 LyP and CD8 anaplastic large cell lymphoma, we found focal to diffuse MUM-1 positivity. We propose that MUM-1 may represent an adjunctive marker for CD8 lymphoproliferative disease. Finally, we review the current literature on cases of CD8 LyP and PCALCL. For the 106 cases examined, we found similar clinical and histologic features to those reported for traditional CD4CD30 LyP and PCALCL.

  18. CD8 chemokine receptors in chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Smyth, L J C; Starkey, C; Gordon, F S

    2008-01-01

    Increased lung CD8 cells and their expression of chemokine receptors CXCR3 and CCR5 have been previously reported in chronic obstructive pulmonary disease (COPD). Alterations of CD8-CCR3 and -CCR4 expression and their ligands in COPD patients have not been fully investigated. The objective...... there was low level CCL11 production. CD8CCR3 and CCR5 expression appear to be regulated by cigarette smoke exposure. We show that COPD lung tissue released more CCL5, suggesting a role for CCL5-CCR3 signalling in pulmonary CD8 recruitment in COPD....... of this study was to assess in COPD patients: (i) broncho-alveolar lavage (BAL) CD8 CCR3 and CCR4 expression in COPD patients; and (ii) airway levels of the CCR3 ligands, CCL11 and CCL5. Multi-parameter flow cytometric analysis was used to assess BAL CD3 and CD8-chemokine receptor expression in COPD patients...

  19. Empty conformers of HLA-B preferentially bind CD8 and regulate CD8+ T cell function.

    Science.gov (United States)

    Geng, Jie; Altman, John D; Krishnakumar, Sujatha; Raghavan, Malini

    2018-05-09

    When complexed with antigenic peptides, human leukocyte antigen (HLA) class I (HLA-I) molecules initiate CD8 + T cell responses via interaction with the T cell receptor (TCR) and co-receptor CD8. Peptides are generally critical for the stable cell surface expression of HLA-I molecules. However, for HLA-I alleles such as HLA-B*35:01, peptide-deficient (empty) heterodimers are thermostable and detectable on the cell surface. Additionally, peptide-deficient HLA-B*35:01 tetramers preferentially bind CD8 and to a majority of blood-derived CD8 + T cells via a CD8-dependent binding mode. Further functional studies reveal that peptide-deficient conformers of HLA-B*35:01 do not directly activate CD8 + T cells, but accumulate at the immunological synapse in antigen-induced responses, and enhance cognate peptide-induced cell adhesion and CD8 + T cell activation. Together, these findings indicate that HLA-I peptide occupancy influences CD8 binding affinity, and reveal a new set of regulators of CD8 + T cell activation, mediated by the binding of empty HLA-I to CD8. © 2018, Geng et al.

  20. Early events governing memory CD8+ T-cell differentiation.

    Science.gov (United States)

    Obar, Joshua J; Lefrançois, Leo

    2010-08-01

    Understanding the regulation of the CD8(+) T-cell response and how protective memory cells are generated has been intensely studied. It is now appreciated that a naive CD8(+) T cell requires at least three signals to mount an effective immune response: (i) TCR triggering, (ii) co-stimulation and (iii) inflammatory cytokines. Only recently have we begun to understand the molecular integration of those signals and how early events regulate the fate decisions of the responding CD8(+) T cells. This review will discuss the recent findings about both the extracellular and intracellular factors that regulate the destiny of responding CD8(+) T cells.

  1. La depleción de las células T regulatorias aumenta el número de las células CD8 durante la infección con el virus del tumor mamario murino

    OpenAIRE

    Gabriel Cabrera; Juliana Mundiñano; Gabriela Camicia; Héctor Costa; Irene Nepomnaschy; Isabel Piazzon

    2011-01-01

    El virus del tumor mamario murino (MMTV) es un retrovirus que se transmite durante la lactancia y que ha desarrollado estrategias para explotar y subvertir el sistema inmune. En un modelo de infección natural con MMTV hemos mostrado previamente que la infección causa incrementos tempranos y progresivos de células T regulatorias (Treg) CD4+CD25+Foxp3+ específicas para el superantígeno (Sag) viral en las placas de Peyer (PP). En este trabajo se evaluó si la depleción de las células Treg influen...

  2. Epigenetic control of CD8+ T cell differentiation.

    Science.gov (United States)

    Henning, Amanda N; Roychoudhuri, Rahul; Restifo, Nicholas P

    2018-05-01

    Upon stimulation, small numbers of naive CD8 + T cells proliferate and differentiate into a variety of memory and effector cell types. CD8 + T cells can persist for years and kill tumour cells and virally infected cells. The functional and phenotypic changes that occur during CD8 + T cell differentiation are well characterized, but the epigenetic states that underlie these changes are incompletely understood. Here, we review the epigenetic processes that direct CD8 + T cell differentiation and function. We focus on epigenetic modification of DNA and associated histones at genes and their regulatory elements. We also describe structural changes in chromatin organization that affect gene expression. Finally, we examine the translational potential of epigenetic interventions to improve CD8 + T cell function in individuals with chronic infections and cancer.

  3. The role of CD8+ T cells during allograft rejection

    Directory of Open Access Journals (Sweden)

    V. Bueno

    2002-11-01

    Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

  4. EBV promotes human CD8 NKT cell development.

    Directory of Open Access Journals (Sweden)

    Yuling He

    2010-05-01

    Full Text Available The reports on the origin of human CD8(+ Valpha24(+ T-cell receptor (TCR natural killer T (NKT cells are controversial. The underlying mechanism that controls human CD4 versus CD8 NKT cell development is not well-characterized. In the present study, we have studied total 177 eligible patients and subjects including 128 healthy latent Epstein-Barr-virus(EBV-infected subjects, 17 newly-onset acute infectious mononucleosis patients, 16 newly-diagnosed EBV-associated Hodgkin lymphoma patients, and 16 EBV-negative normal control subjects. We have established human-thymus/liver-SCID chimera, reaggregated thymic organ culture, and fetal thymic organ culture. We here show that the average frequency of total and CD8(+ NKT cells in PBMCs from 128 healthy latent EBV-infected subjects is significantly higher than in 17 acute EBV infectious mononucleosis patients, 16 EBV-associated Hodgkin lymphoma patients, and 16 EBV-negative normal control subjects. However, the frequency of total and CD8(+ NKT cells is remarkably increased in the acute EBV infectious mononucleosis patients at year 1 post-onset. EBV-challenge promotes CD8(+ NKT cell development in the thymus of human-thymus/liver-SCID chimeras. The frequency of total (3% of thymic cells and CD8(+ NKT cells ( approximately 25% of NKT cells is significantly increased in EBV-challenged chimeras, compared to those in the unchallenged chimeras (<0.01% of thymic cells, CD8(+ NKT cells undetectable, respectively. The EBV-induced increase in thymic NKT cells is also reflected in the periphery, where there is an increase in total and CD8(+ NKT cells in liver and peripheral blood in EBV-challenged chimeras. EBV-induced thymic CD8(+ NKT cells display an activated memory phenotype (CD69(+CD45RO(hiCD161(+CD62L(lo. After EBV-challenge, a proportion of NKT precursors diverges from DP thymocytes, develops and differentiates into mature CD8(+ NKT cells in thymus in EBV-challenged human-thymus/liver-SCID chimeras or

  5. Mast-Cell-Derived TNF Amplifies CD8+ Dendritic Cell Functionality and CD8+ T Cell Priming

    Directory of Open Access Journals (Sweden)

    Jan Dudeck

    2015-10-01

    Full Text Available Mast cells are critical promoters of adaptive immunity in the contact hypersensitivity model, but the mechanism of allergen sensitization is poorly understood. Using Mcpt5-CreTNFFL/FL mice, we show here that the absence of TNF exclusively in mast cells impaired the expansion of CD8+ T cells upon sensitization and the T-cell-driven adaptive immune response to elicitation. T cells primed in the absence of mast cell TNF exhibited a diminished efficiency to transfer sensitization to naive recipients. Specifically, mast cell TNF promotes CD8+ dendritic cell (DC maturation and migration to draining lymph nodes. The peripherally released mast cell TNF further critically boosts the CD8+ T-cell-priming efficiency of CD8+ DCs, thereby linking mast cell effects on T cells to DC modulation. Collectively, our findings identify the distinct potential of mast cell TNF to amplify CD8+ DC functionality and CD8+ T-cell-dominated adaptive immunity, which may be of great importance for immunotherapy and vaccination approaches.

  6. Functional heterogeneity of human effector CD8+ T cells.

    Science.gov (United States)

    Takata, Hiroshi; Naruto, Takuya; Takiguchi, Masafumi

    2012-02-09

    Effector CD8(+) T cells are believed to be terminally differentiated cells having cytotoxic activity and the ability to produce effector cytokines such as INF-γ and TNF-α. We investigated the difference between CXCR1(+) and CXCR1(-) subsets of human effector CD27(-)CD28(-)CD8(+) T cells. The subsets expressed cytolytic molecules similarly and exerted substantial cytolytic activity, whereas only the CXCR1(-) subset had IL-2 productivity and self-proliferative activity and was more resistant to cell death than the CXCR1(+) subset. These differences were explained by the specific up-regulation of CAMK4, SPRY2, and IL-7R in the CXCR1(-) subset and that of pro-apoptotic death-associated protein kinase 1 (DAPK1) in the CXCR1(+) subset. The IL-2 producers were more frequently found in the IL-7R(+) subset of the CXCR1(-) effector CD8(+) T cells than in the IL-7R(-) subset. IL-7/IL-7R signaling promoted cell survival only in the CXCR1(-) subset. The present study has highlighted a novel subset of effector CD8(+) T cells producing IL-2 and suggests the importance of this subset in the homeostasis of effector CD8(+) T cells.

  7. Human influenza viruses and CD8(+) T cell responses.

    Science.gov (United States)

    Grant, Emma J; Quiñones-Parra, Sergio M; Clemens, E Bridie; Kedzierska, Katherine

    2016-02-01

    Influenza A viruses (IAVs) cause significant morbidity and mortality worldwide, despite new strain-specific vaccines being available annually. As IAV-specific CD8(+) T cells promote viral control in the absence of neutralizing antibodies, and can mediate cross-reactive immunity toward distinct IAVs to drive rapid recovery from both mild and severe influenza disease, there is great interest in developing a universal T cell vaccine. However, despite detailed studies in mouse models of influenza virus infection, there is still a paucity of data on human epitope-specific CD8(+) T cell responses to IAVs. This review focuses on our current understanding of human CD8(+) T cell immunity against distinct IAVs and discusses the possibility of achieving a CD8(+) T cell mediated-vaccine that protects against multiple, distinct IAV strains across diverse human populations. We also review the importance of CD8(+) T cell immunity in individuals highly susceptible to severe influenza infection, including those hospitalised with influenza, the elderly and Indigenous populations. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The CD8 T Cell Response to Respiratory Virus Infections.

    Science.gov (United States)

    Schmidt, Megan E; Varga, Steven M

    2018-01-01

    Humans are highly susceptible to infection with respiratory viruses including respiratory syncytial virus (RSV), influenza virus, human metapneumovirus, rhinovirus, coronavirus, and parainfluenza virus. While some viruses simply cause symptoms of the common cold, many respiratory viruses induce severe bronchiolitis, pneumonia, and even death following infection. Despite the immense clinical burden, the majority of the most common pulmonary viruses lack long-lasting efficacious vaccines. Nearly all current vaccination strategies are designed to elicit broadly neutralizing antibodies, which prevent severe disease following a subsequent infection. However, the mucosal antibody response to many respiratory viruses is not long-lasting and declines with age. CD8 T cells are critical for mediating clearance following many acute viral infections in the lung. In addition, memory CD8 T cells are capable of providing protection against secondary infections. Therefore, the combined induction of virus-specific CD8 T cells and antibodies may provide optimal protective immunity. Herein, we review the current literature on CD8 T cell responses induced by respiratory virus infections. Additionally, we explore how this knowledge could be utilized in the development of future vaccines against respiratory viruses, with a special emphasis on RSV vaccination.

  9. Multi-scale modeling of the CD8 immune response

    Energy Technology Data Exchange (ETDEWEB)

    Barbarroux, Loic, E-mail: loic.barbarroux@doctorant.ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Michel, Philippe, E-mail: philippe.michel@ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Adimy, Mostafa, E-mail: mostafa.adimy@inria.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France); Crauste, Fabien, E-mail: crauste@math.univ-lyon1.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France)

    2016-06-08

    During the primary CD8 T-Cell immune response to an intracellular pathogen, CD8 T-Cells undergo exponential proliferation and continuous differentiation, acquiring cytotoxic capabilities to address the infection and memorize the corresponding antigen. After cleaning the organism, the only CD8 T-Cells left are antigen-specific memory cells whose role is to respond stronger and faster in case they are presented this very same antigen again. That is how vaccines work: a small quantity of a weakened pathogen is introduced in the organism to trigger the primary response, generating corresponding memory cells in the process, giving the organism a way to defend himself in case it encounters the same pathogen again. To investigate this process, we propose a non linear, multi-scale mathematical model of the CD8 T-Cells immune response due to vaccination using a maturity structured partial differential equation. At the intracellular scale, the level of expression of key proteins is modeled by a delay differential equation system, which gives the speeds of maturation for each cell. The population of cells is modeled by a maturity structured equation whose speeds are given by the intracellular model. We focus here on building the model, as well as its asymptotic study. Finally, we display numerical simulations showing the model can reproduce the biological dynamics of the cell population for both the primary response and the secondary responses.

  10. Cytokines and the Inception of CD8 T Cell Responses

    Science.gov (United States)

    Cox, Maureen A.; Harrington, Laurie E.; Zajac, Allan J.

    2011-01-01

    The activation and differentiation of CD8 T cells is a necessary first step that endows these cells with the phenotypic and functional properties required for the control of intracellular pathogens. The induction of the CD8 T cell responses typically results in the development of a massive overall population of effector cells, comprised of both highly functional but short-lived terminally differentiated cells, as well as a smaller subset of precursors that are predisposed to survive and transition into the memory T cell pool. In this article we discuss how inflammatory cytokines and IL-2 bias the initial response towards short-lived effector generation and also highlight the potential counterbalancing role of IL-21. PMID:21371940

  11. CD4dullCD8bright double-positive T-lymphocytes have a phenotype of granzyme Bpos CD8pos memory T-lymphocytes

    NARCIS (Netherlands)

    Rentenaar, R. J.; Wever, P. C.; van Diepen, F. N.; Schellekens, P. T.; Wertheim, P. M.; ten Berge, I. J.

    1999-01-01

    BACKGROUND: T-lymphocytes that co-express CD4 and CD8 antigens may be found in small percentages in the peripheral blood of healthy individuals, and have a CD4brightCD8dull phenotype. CD4dullCD8bright T-lymphocytes have been found only in temporal association with some viral infections. METHODS:

  12. Peptide pool immunization and CD8+ T cell reactivity

    DEFF Research Database (Denmark)

    Rasmussen, Susanne B; Harndahl, Mikkel N; Buus, Anette Stryhn

    2013-01-01

    Mice were immunized twice with a pool of five peptides selected among twenty 8-9-mer peptides for their ability to form stable complexes at 37°C with recombinant H-2K(b) (half-lives 10-15h). Vaccine-induced immunity of splenic CD8(+) T cells was studied in a 24h IFNγ Elispot assay. Surprisingly...... peptides induced normal peptide immunity i.e. the specific T cell reactivity in the Elispot culture was strictly dependent on exposure to the immunizing peptide ex vivo. However, immunization with two of the peptides, a VSV- and a Mycobacterium-derived peptide, resulted in IFNγ spot formation without...... peptide in the Elispot culture. Immunization with a mixture of the VSV-peptide and a "normal" peptide also resulted in IFNγ spot formation without addition of peptide to the assay culture. Peptide-tetramer staining of CD8(+) T cells from mice immunized with a mixture of VSV-peptide and "normal" peptide...

  13. Targeting CD8+ T-cell tolerance for cancer immunotherapy.

    Science.gov (United States)

    Jackson, Stephanie R; Yuan, Jinyun; Teague, Ryan M

    2014-01-01

    In the final issue of Science in 2013, the American Association of Science recognized progress in the field of cancer immunotherapy as the 'Breakthrough of the Year.' The achievements were actually twofold, owing to the early success of genetically engineered chimeric antigen receptors (CAR) and to the mounting clinical triumphs achieved with checkpoint blockade antibodies. While fundamentally very different, the common thread of these independent strategies is the ability to prevent or overcome mechanisms of CD8(+) T-cell tolerance for improved tumor immunity. Here we discuss how circumventing T-cell tolerance has provided experimental insights that have guided the field of clinical cancer immunotherapy to a place where real breakthroughs can finally be claimed.

  14. Evaluation of CD4+/CD8+ status and urinary tract infections ...

    African Journals Online (AJOL)

    Evaluation of CD4+/CD8+ status and urinary tract infections associated with urinary schistosomiasis ... African Health Sciences ... by <50 ova /10ml of urine had a mean CD4+:CD8+ ratio of 1.57 while those with heavy infections as ... Key words: CD4+, CD8+, urinary tract infections, urinary schistosomiasis, rural Nigerians

  15. CD8+ T cells in human autoimmune arthritis : The unusual suspects

    NARCIS (Netherlands)

    Petrelli, Alessandra; Van Wijk, Femke

    2016-01-01

    CD8+ T cells are key players in the body's defence against viral infections and cancer. To date, data on the role of CD8+ T cells in autoimmune diseases have been scarce, especially when compared with the wealth of research on CD4+ T cells. However, growing evidence suggests that CD8+ T-cell

  16. Requirement for CD4 T Cell Help in Generating Functional CD8 T Cell Memory

    Science.gov (United States)

    Shedlock, Devon J.; Shen, Hao

    2003-04-01

    Although primary CD8 responses to acute infections are independent of CD4 help, it is unknown whether a similar situation applies to secondary responses. We show that depletion of CD4 cells during the recall response has minimal effect, whereas depletion during the priming phase leads to reduced responses by memory CD8 cells to reinfection. Memory CD8 cells generated in CD4+/+ mice responded normally when transferred into CD4-/- hosts, whereas memory CD8 cells generated in CD4-/- mice mounted defective recall responses in CD4+/+ adoptive hosts. These results demonstrate a previously undescribed role for CD4 help in the development of functional CD8 memory.

  17. Increased numbers of preexisting memory CD8 T cells and decreased T-bet expression can restrain terminal differentiation of secondary effector and memory CD8 T cells.

    Science.gov (United States)

    Joshi, Nikhil S; Cui, Weiguo; Dominguez, Claudia X; Chen, Jonathan H; Hand, Timothy W; Kaech, Susan M

    2011-10-15

    Memory CD8 T cells acquire effector memory cell properties after reinfection and may reach terminally differentiated, senescent states ("Hayflick limit") after multiple infections. The signals controlling this process are not well understood, but we found that the degree of secondary effector and memory CD8 T cell differentiation was intimately linked to the amount of T-bet expressed upon reactivation and preexisting memory CD8 T cell number (i.e., primary memory CD8 T cell precursor frequency) present during secondary infection. Compared with naive cells, memory CD8 T cells were predisposed toward terminal effector (TE) cell differentiation because they could immediately respond to IL-12 and induce T-bet, even in the absence of Ag. TE cell formation after secondary (2°) or tertiary infections was dependent on increased T-bet expression because T-bet(+/-) cells were resistant to these phenotypic changes. Larger numbers of preexisting memory CD8 T cells limited the duration of 2° infection and the amount of IL-12 produced, and consequently, this reduced T-bet expression and the proportion of 2° TE CD8 T cells that formed. Together, these data show that over repeated infections, memory CD8 T cell quality and proliferative fitness is not strictly determined by the number of serial encounters with Ag or cell divisions, but is a function of the CD8 T cell differentiation state, which is genetically controlled in a T-bet-dependent manner. This differentiation state can be modulated by preexisting memory CD8 T cell number and the intensity of inflammation during reinfection. These results have important implications for vaccinations involving prime-boost strategies.

  18. CD4/CD8/Dendritic cell complexes in the spleen: CD8+ T cells can directly bind CD4+ T cells and modulate their response

    Science.gov (United States)

    Barinov, Aleksandr; Galgano, Alessia; Krenn, Gerald; Tanchot, Corinne; Vasseur, Florence

    2017-01-01

    CD4+ T cell help to CD8+ T cell responses requires that CD4+ and CD8+ T cells interact with the same antigen presenting dendritic cell (Ag+DC), but it remains controversial whether helper signals are delivered indirectly through a licensed DC and/or involve direct CD4+/CD8+ T cell contacts and/or the formation of ternary complexes. We here describe the first in vivo imaging of the intact spleen, aiming to evaluate the first interactions between antigen-specific CD4+, CD8+ T cells and Ag+DCs. We show that in contrast to CD4+ T cells which form transient contacts with Ag+DC, CD8+ T cells form immediate stable contacts and activate the Ag+DC, acquire fragments of the DC membranes by trogocytosis, leading to their acquisition of some of the DC properties. They express MHC class II, and become able to present the specific Marilyn peptide to naïve Marilyn CD4+ T cells, inducing their extensive division. In vivo, these CD8+ T cells form direct stable contacts with motile naïve CD4+ T cells, recruiting them to Ag+DC binding and to the formation of ternary complexes, where CD4+ and CD8+ T cells interact with the DC and with one another. The presence of CD8+ T cells during in vivo immune responses leads to the early activation and up-regulation of multiple functions by CD4+ T lymphocytes. Thus, while CD4+ T cell help is important to CD8+ T cell responses, CD8+ T cells can interact directly with naïve CD4+ T cells impacting their recruitment and differentiation. PMID:28686740

  19. Hypoxia Enhances Immunosuppression by Inhibiting CD4+ Effector T Cell Function and Promoting Treg Activity

    Directory of Open Access Journals (Sweden)

    Astrid M. Westendorf

    2017-03-01

    Full Text Available Background/Aims: Hypoxia occurs in many pathological conditions, including inflammation and cancer. Within this context, hypoxia was shown to inhibit but also to promote T cell responses. Due to this controversial function, we aimed to explore whether an insufficient anti-tumour response during colitis-associated colon cancer could be ascribed to a hypoxic microenvironment. Methods: Colitis-associated colon cancer was induced in wildtype mice, and hypoxia as well as T cell immunity were analysed in the colonic tumour tissues. In addition, CD4+ effector T cells and regulatory T cells were cultured under normoxic and hypoxic conditions and examined regarding their phenotype and function. Results: We observed severe hypoxia in the colon of mice suffering from colitis-associated colon cancer that was accompanied by a reduced differentiation of CD4+ effector T cells and an enhanced number and suppressive activity of regulatory T cells. Complementary ex vivo and in vitro studies revealed that T cell stimulation under hypoxic conditions inhibited the differentiation, proliferation and IFN-γ production of TH1 cells and enhanced the suppressive capacity of regulatory T cells. Moreover, we identified an active role for HIF-1α in the modulation of CD4+ T cell functions under hypoxic conditions. Conclusion: Our data indicate that oxygen availability can function as a local modulator of CD4+ T cell responses and thus influences tumour immune surveillance in inflammation-associated colon cancer.

  20. Distinct Th1, Th2 and Treg cytokines balance in chronic periapical granulomas and radicular cysts.

    Science.gov (United States)

    Teixeira-Salum, Tatiana Beber; Rodrigues, Denise Bertulucci Rocha; Gervásio, Aurélia M; Souza, Cássio J A; Rodrigues, Virmondes; Loyola, Adriano Motta

    2010-03-01

    Periapical lesions are a host response that involves immune reaction to prevent dissemination of bacteria from an infected root canal. The purpose of this study was to evaluate the levels of nitric oxide (NO), IL-4, TGF-beta, tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) in chronic periapical lesions and to determine their possible association with clinical and radiographic parameters. Seventeen human radicular cysts and 30 periapical granulomas were used in this study. Cytokines and NO were assessed by enzyme-linked immunosorbent assay and by the Griess reaction respectively confirmed by immunohistochemical. TNF-alpha and IFN-gamma were detected in 10% of granulomas and in 41.2% and 70% of radicular cysts. IL-4 was reactive in 24% of cysts, and TGF-beta was positive in all samples. Patients with tenderness showed significantly higher levels of IFN-gamma and IL-4 (P Periapical granulomas display a regulatory environment characterized by high TGF-beta and low inflammatory cytokine levels, while radicular cysts has mist Th1 and Th2 inflammatory reaction with the presence of IFN-gamma, TNF-alpha, and IL-4.

  1. Histone deacetylase inhibition regulates inflammation and enhances Tregs after allogeneic hematopoietic cell transplantation in humans

    NARCIS (Netherlands)

    Choi, S.W.; Gatza, E.; Hou, G.; Sun, Y; Whitfield, J.; Song, Y.; Oravecz-Wilson, K.; Tawara, I.; Dinarello, C.A.; Reddy, P.

    2015-01-01

    We examined immunological responses in patients receiving histone deacetylase (HDAC) inhibition (vorinostat) for graft-versus-host disease prophylaxis after allogeneic hematopoietic cell transplant. Vorinostat treatment increased histone acetylation in peripheral blood mononuclear cells (PBMCs) from

  2. Association between CD8 T-cell subsets and CD4/CD8 ratio with HS-CRP level in HIV-infected patients on antiretroviral therapy

    Science.gov (United States)

    Isabela, S.; Nugroho, A.; Harijanto, P. N.

    2018-03-01

    Due to improved access and adherence to antiretroviral therapy (ART), most HIV-infected persons worldwide are predicted to live longer. Nowadays the cause of death for most HIV-infected persons has changed to serious non-AIDS events (SNAEs) which is due to low-grade viremia. HIV patients with ART who had undergone CD4 cell count above 500/uL and there is an increase in hs-CRP despite an undetectable viral load. Some conditions CD8 cells count do not decrease with CD4 cells repairs. We researched in Prof Kandou General Hospital with a total sample of 35 HIV patients who had received ART with the level of CD4>350/uL. CD8 levels, CD4/CD8 ratio, and hs-CRP were assessed. This research is analytic descriptive with cross-sectional study design and analysis uses Spearman correlation. The mean CD8 during the study was 1291.8 (IQR 319-2610cells/uL), the mean ratio of CD4:CD8 was 0.57 (IQR 0.16-1.24) and median hs-CRP is 2.18 (IQR 0.3-6.6mg/dL). There was a significant positive correlation between CD8 and increased hs-CRP (r=0.369, pCD4/CD8 ratio and hs-CRP (r=-0.370, p<0.05).

  3. Control of mucosal virus infection by influenza nucleoprotein-specific CD8+ cytotoxic T lymphocytes

    Directory of Open Access Journals (Sweden)

    Couch Robert B

    2007-06-01

    Full Text Available Abstract Background MHC class I-restricted CD8+ cytotoxic T lymphocytes (CTL are thought to play a major role in clearing virus and promoting recovery from influenza infection and disease. This has been demonstrated for clearance of influenza virus from the lungs of infected mice. However, human influenza infection is primarily a respiratory mucosal infection involving the nasopharynx and tracheobronchial tree. The role of CD8+ CTL directed toward the influenza nucleoprotein (NP in defense against influenza virus infection at the respiratory mucosa was evaluated in two separate adoptive transfer experiments. Methods Influenza nucleoprotein (NP-specific CD8+ CTL were generated from splenocytes obtained from Balb/c mice previously primed with influenza A/Taiwan/1/86 (H1N1 infection or with influenza A/PR/8/34 (H1N1-derived NP plasmid DNA vaccine followed by infection with A/Hong Kong/68 (H3N2 virus. After in vitro expansion by exposure to an influenza NP-vaccinia recombinant, highly purified CD8+ T cells exhibited significant lysis in vitro of P815 target cells infected with A/Hong Kong/68 (H3N2 virus while the CD8- fraction (CD4+ T cells, B cells and macrophages had no CTL activity. Purified CD8+ and CD8- T cells (1 × 107 were injected intravenously or interperitoneally into naive mice four hours prior to intranasal challenge with A/HK/68 (H3N2 virus. Results The adoptively transferred NP-vaccinia-induced CD8+ T cells caused significant reduction of virus titers in both the lungs and nasal passages when compared to CD8- cells. Neither CD8+ nor CD8- T cells from cultures stimulated with HIV gp120-vaccinia recombinant reduced virus titers. Conclusion The present data demonstrate that influenza NP-specific CD8+ CTL can play a direct role in clearance of influenza virus from the upper respiratory mucosal surfaces.

  4. Oral Salmonella: malaria circumsporozoite recombinants induce specific CD8+ cytotoxic T cells

    OpenAIRE

    1990-01-01

    Oral immunization with an attenuated Salmonella typhimurium recombinant containing the full-length Plasmodium berghei circumsporozoite (CS) gene induces protective immunity against P. berghei sporozoite challenge in the absence of antibody. We found that this immunity was mediated through the induction of specific CD8+ T cells since in vivo elimination of CD8+ cells abrogated protection. In vitro studies revealed that this Salmonella-P. berghei CS recombinant induced class I- restricted CD8+ ...

  5. Acetylation of the Cd8 Locus by KAT6A Determines Memory T Cell Diversity

    Directory of Open Access Journals (Sweden)

    Dane M. Newman

    2016-09-01

    Full Text Available How functionally diverse populations of pathogen-specific killer T cells are generated during an immune response remains unclear. Here, we propose that fine-tuning of CD8αβ co-receptor levels via histone acetylation plays a role in lineage fate. We show that lysine acetyltransferase 6A (KAT6A is responsible for maintaining permissive Cd8 gene transcription and enabling robust effector responses during infection. KAT6A-deficient CD8+ T cells downregulated surface CD8 co-receptor expression during clonal expansion, a finding linked to reduced Cd8α transcripts and histone-H3 lysine 9 acetylation of the Cd8 locus. Loss of CD8 expression in KAT6A-deficient T cells correlated with reduced TCR signaling intensity and accelerated contraction of the effector-like memory compartment, whereas the long-lived memory compartment appeared unaffected, a result phenocopied by the removal of the Cd8 E8I enhancer element. These findings suggest a direct role of CD8αβ co-receptor expression and histone acetylation in shaping functional diversity within the cytotoxic T cell pool.

  6. Sustained CD8+ T-cell responses induced after acute parvovirus B19 infection in humans

    DEFF Research Database (Denmark)

    Norbeck, Oscar; Isa, Adiba; Pöhlmann, Christoph

    2005-01-01

    Murine models have suggested that CD8+ T-cell responses peak early in acute viral infections and are not sustained, but no evidence for humans has been available. To address this, we longitudinally analyzed the CD8+ T-cell response to human parvovirus B19 in acutely infected individuals. We...... observed striking CD8+ T-cell responses, which were sustained or even increased over many months after the resolution of acute disease, indicating that CD8+ T cells may play a prominent role in the control of parvovirus B19 and other acute viral infections of humans, including potentially those generated...

  7. Linfocitos T citotóxicos CD8+ en la leishmaniasis cutánea CD8+ cytotoxic lymphocytes in cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Joselín Hernández-Ruiz

    2006-10-01

    Full Text Available OBJETIVO: Examinar la bibliografía relacionada con la participación de los linfocitos T CD8+ en la reacción inmunitaria a especies de Leishmania causantes de leishmaniasis cutánea. En esta enfermedad se ha resaltado la intervención de macrófagos, células dendríticas, NK y células T CD4+; sin embargo, es poco lo que se conoce de las células T CD8+. Los trabajos en modelos murinos señalan que la participación de las células CD8+ sucede a través de la producción de IFN-gamma, aunque su capacidad citotóxica puede desempeñar una función importante, como lo demuestran los hallazgos en seres humanos. La forma como se activan las células citotóxicas CD8+ es un enigma. Es posible que las células dendríticas realicen esa labor a través de mecanismos que incluyen transpresentación de antígenos. Comprender la contribución de este subtipo celular en la respuesta inmunitaria a Leishmania aportará novedosos conocimientos sobre la fisiopatogenia de la leishmaniasis, lo cual hará posible desarrollar nuevos enfoques terapéuticos para esta parasitosis.OBJECTIVE: Review of the literature on the role of CD8+ T cell in the immune response against Leishmania species that cause cutaneous leishmaniasis. The role of macrophages, dendritic cells, CD4 T cells and NK cells has been extensively analyzed in leishmaniasis, yet very little knowledge has been gained on CD8+ T cells in this disease. Murine models of leishmaniasis suggest that CD8+ T cells participate through IFNg production, yet their cytotoxic capacity may also play a crucial role, as has been found in human disease. It is an enigma what mechanisms underlie the CD8+ T cell activation. It is possible that dendritic cells activate CD8+ T cells through mechanisms that include antigen traspresentation. A better understanding of CD8+ T cells in the immune response against Leishmania will undoubtedly provide new insights into the physiopathogenesis of the disease that could lead to new

  8. Memory CD8+ T cells protect dendritic cells from CTL killing

    NARCIS (Netherlands)

    Watchmaker, Payal B.; Urban, Julie A.; Berk, Erik; Nakamura, Yutaro; Mailliard, Robbie B.; Watkins, Simon C.; van Ham, S. Marieke; Kalinski, Pawel

    2008-01-01

    CD8(+) T cells have been shown to be capable of either suppressing or promoting immune responses. To reconcile these contrasting regulatory functions, we compared the ability of human effector and memory CD8(+) T cells to regulate survival and functions of dendritic cells (DC). We report that, in

  9. Human CD8 T cells generated in vitro from hematopoietic stem cells are functionally mature

    Directory of Open Access Journals (Sweden)

    Zúñiga-Pflücker Juan

    2011-03-01

    Full Text Available Abstract Background T cell development occurs within the highly specialized thymus. Cytotoxic CD8 T cells are critical in adaptive immunity by targeting virally infected or tumor cells. In this study, we addressed whether functional CD8 T cells can be generated fully in vitro using human umbilical cord blood (UCB hematopoietic stem cells (HSCs in coculture with OP9-DL1 cells. Results HSC/OP9-DL1 cocultures supported the differentiation of CD8 T cells, which were TCR/CD3hi CD27hi CD1aneg and thus phenotypically resembled mature functional CD8 single positive thymocytes. These in vitro-generated T cells also appeared to be conventional CD8 cells, as they expressed high levels of Eomes and low levels of Plzf, albeit not identical to ex vivo UCB CD8 T cells. Consistent with the phenotypic and molecular characterization, upon TCR-stimulation, in vitro-generated CD8 T cells proliferated, expressed activation markers (MHC-II, CD25, CD38, secreted IFN-γ and expressed Granzyme B, a cytotoxic T-cell effector molecule. Conclusion Taken together, the ability to direct human hematopoietic stem cell or T-progenitor cells towards a mature functional phenotype raises the possibility of establishing cell-based treatments for T-immunodeficiencies by rapidly restoring CD8 effector function, thereby mitigating the risks associated with opportunistic infections.

  10. Mechanisms of CD8+ T cell-mediated suppression of HIV/SIV replication.

    Science.gov (United States)

    McBrien, Julia Bergild; Kumar, Nitasha A; Silvestri, Guido

    2018-02-10

    In this article, we summarize the role of CD8 + T cells during natural and antiretroviral therapy (ART)-treated HIV and SIV infections, discuss the mechanisms responsible for their suppressive activity, and review the rationale for CD8 + T cell-based HIV cure strategies. Evidence suggests that CD8 + T cells are involved in the control of virus replication during HIV and SIV infections. During early HIV infection, the cytolytic activity of CD8 + T cells is responsible for control of viremia. However, it has been proposed that CD8 + T cells also use non-cytolytic mechanisms to control SIV infection. More recently, CD8 + T cells were shown to be required to fully suppress virus production in ART-treated SIV-infected macaques, suggesting that CD8 + T cells are involved in the control of virus transcription in latently infected cells that persist under ART. A better understanding of the complex antiviral activities of CD8 + T cells during HIV/SIV infection will pave the way for immune interventions aimed at harnessing these functions to target the HIV reservoir. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Intrinsic and extrinsic contributors to defective CD8+ T cell responses with aging.

    Science.gov (United States)

    Jergović, Mladen; Smithey, Megan J; Nikolich-Žugich, Janko

    2018-05-01

    Aging has a profound effect on the immune system, and both innate and adaptive arms of the immune system show functional decline with age. In response to infection with intracellular microorganisms, old animals mobilize decreased numbers of antigen-specific CD8+ T cells with reduced production of effector molecules and impaired cytolytic activity. However, the CD8+ T cell-intrinsic contribution to, and molecular mechanisms behind, these defects remain unclear. In this review we will discuss the mechanistic contributions of age related changes in the CD8+ T cell pool and the relative roles of intrinsic functional defects in aged CD8+ T cells vs. defects in the aged environment initiating the CD8+ T cell response. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. A Low Peripheral Blood CD4/CD8 Ratio Is Associated with Pulmonary Emphysema in HIV.

    Science.gov (United States)

    Triplette, Matthew; Attia, Engi F; Akgün, Kathleen M; Soo Hoo, Guy W; Freiberg, Matthew S; Butt, Adeel A; Wongtrakool, Cherry; Goetz, Matthew Bidwell; Brown, Sheldon T; Graber, Christopher J; Huang, Laurence; Crothers, Kristina

    2017-01-01

    The prevalence of emphysema is higher among HIV-infected (HIV+) individuals compared to HIV-uninfected persons. While greater tobacco use contributes, HIV-related effects on immunity likely confer additional risk. Low peripheral blood CD4+ to CD8+ T-lymphocyte (CD4/CD8) ratio may reflect chronic inflammation in HIV and may be a marker of chronic lung disease in this population. Therefore, we sought to determine whether the CD4/CD8 ratio was associated with chronic obstructive pulmonary disease (COPD), particularly the emphysema subtype, in a cohort of HIV+ subjects. We performed a cross-sectional analysis of 190 HIV+ subjects enrolled in the Examinations of HIV Associated Lung Emphysema (EXHALE) study. Subjects underwent baseline laboratory assessments, pulmonary function testing and chest computed tomography (CT) analyzed for emphysema severity and distribution. We determined the association between CD4/CD8 ratio and emphysema, and the association between CD4/CD8 ratio and pulmonary function markers of COPD. Mild or greater emphysema (>10% lung involvement) was present in 31% of subjects. Low CD4/CD8 ratio was associated with >10% emphysema in multivariable models, adjusting for risk factors including smoking, current and nadir CD4 count and HIV RNA level. Those with CD4/CD8 ratio 10% emphysema compared to those with a ratio >1.0 in fully adjusted models. A low CD4/CD8 ratio was also associated with reduced diffusion capacity (DLCO). A low CD4/CD8 ratio was associated with emphysema and low DLCO in HIV+ subjects, independent of other risk factors and clinical markers of HIV. The CD4/CD8 ratio may be a useful, clinically available, marker for risk of emphysema in HIV+ subjects in the antiretroviral therapy (ART) era.

  13. FOXO3 regulates CD8 T cell memory by T cell-intrinsic mechanisms.

    Directory of Open Access Journals (Sweden)

    Jeremy A Sullivan

    2012-02-01

    Full Text Available CD8 T cell responses have three phases: expansion, contraction, and memory. Dynamic alterations in proliferation and apoptotic rates control CD8 T cell numbers at each phase, which in turn dictate the magnitude of CD8 T cell memory. Identification of signaling pathways that control CD8 T cell memory is incomplete. The PI3K/Akt signaling pathway controls cell growth in many cell types by modulating the activity of FOXO transcription factors. But the role of FOXOs in regulating CD8 T cell memory remains unknown. We show that phosphorylation of Akt, FOXO and mTOR in CD8 T cells occurs in a dynamic fashion in vivo during an acute viral infection. To elucidate the potentially dynamic role for FOXO3 in regulating homeostasis of activated CD8 T cells in lymphoid and non-lymphoid organs, we infected global and T cell-specific FOXO3-deficient mice with Lymphocytic Choriomeningitis Virus (LCMV. We found that FOXO3 deficiency induced a marked increase in the expansion of effector CD8 T cells, preferentially in the spleen, by T cell-intrinsic mechanisms. Mechanistically, the enhanced accumulation of proliferating CD8 T cells in FOXO3-deficient mice was not attributed to an augmented rate of cell division, but instead was linked to a reduction in cellular apoptosis. These data suggested that FOXO3 might inhibit accumulation of growth factor-deprived proliferating CD8 T cells by reducing their viability. By virtue of greater accumulation of memory precursor effector cells during expansion, the numbers of memory CD8 T cells were strikingly increased in the spleens of both global and T cell-specific FOXO3-deficient mice. The augmented CD8 T cell memory was durable, and FOXO3 deficiency did not perturb any of the qualitative attributes of memory T cells. In summary, we have identified FOXO3 as a critical regulator of CD8 T cell memory, and therapeutic modulation of FOXO3 might enhance vaccine-induced protective immunity against intracellular pathogens.

  14. Distinct and overlapping effector functions of expanded human CD4+, CD8α+ and CD4-CD8α- invariant natural killer T cells.

    Directory of Open Access Journals (Sweden)

    Vincent O'Reilly

    Full Text Available CD1d-restricted invariant natural killer T (iNKT cells have diverse immune stimulatory/regulatory activities through their ability to release cytokines and to kill or transactivate other cells. Activation of iNKT cells can protect against multiple diseases in mice but clinical trials in humans have had limited impact. Clinical studies to date have targeted polyclonal mixtures of iNKT cells and we proposed that their subset compositions will influence therapeutic outcomes. We sorted and expanded iNKT cells from healthy donors and compared the phenotypes, cytotoxic activities and cytokine profiles of the CD4(+, CD8α(+ and CD4(-CD8α(- double-negative (DN subsets. CD4(+ iNKT cells expanded more readily than CD8α(+ and DN iNKT cells upon mitogen stimulation. CD8α(+ and DN iNKT cells most frequently expressed CD56, CD161 and NKG2D and most potently killed CD1d(+ cell lines and primary leukemia cells. All iNKT subsets released Th1 (IFN-γ and TNF-α and Th2 (IL-4, IL-5 and IL-13 cytokines. Relative amounts followed a CD8α>DN>CD4 pattern for Th1 and CD4>DN>CD8α for Th2. All iNKT subsets could simultaneously produce IFN-γ and IL-4, but single-positivity for IFN-γ or IL-4 was strikingly rare in CD4(+ and CD8α(+ fractions, respectively. Only CD4(+ iNKT cells produced IL-9 and IL-10; DN cells released IL-17; and none produced IL-22. All iNKT subsets upregulated CD40L upon glycolipid stimulation and induced IL-10 and IL-12 secretion by dendritic cells. Thus, subset composition of iNKT cells is a major determinant of function. Use of enriched CD8α(+, DN or CD4(+ iNKT cells may optimally harness the immunoregulatory properties of iNKT cells for treatment of disease.

  15. CD8+ T cells induce thyroid epithelial cell hyperplasia and fibrosis.

    Science.gov (United States)

    Yu, Shiguang; Fang, Yujiang; Sharav, Tumenjargal; Sharp, Gordon C; Braley-Mullen, Helen

    2011-02-15

    CD8(+) T cells can be important effector cells in autoimmune inflammation, generally because they can damage target cells by cytotoxicity. This study shows that activated CD8(+) T cells induce thyroid epithelial cell hyperplasia and proliferation and fibrosis in IFN-γ(-/-) NOD.H-2h4 SCID mice in the absence of CD4(+) T cells. Because CD8(+) T cells induce proliferation rather than cytotoxicity of target cells, these results describe a novel function for CD8(+) T cells in autoimmune disease. In contrast to the ability of purified CD8(+) T cells to induce thyrocyte proliferation, CD4(+) T cells or CD8 T cell-depleted splenocytes induced only mild thyroid lesions in SCID recipients. T cells in both spleens and thyroids highly produce TNF-α. TNF-α promotes proliferation of thyrocytes in vitro, and anti-TNF-α inhibits development of thyroid epithelial cell hyperplasia and proliferation in SCID recipients of IFN-γ(-/-) splenocytes. This suggests that targeting CD8(+) T cells and/or TNF-α may be effective for treating epithelial cell hyperplasia and fibrosis.

  16. CD8 T-cells and E-cadherin in host responses against oropharyngeal candidiasis

    Science.gov (United States)

    Quimby, K.; Lilly, E.A.; Zacharek, M.; McNulty, K.; Leigh, J.E.; Vazquez, J.E.; Fidel, P.L.

    2011-01-01

    Oropharyngeal candidiasis (OPC) is the most common oral infection in HIV+ persons. Previous studies suggest a role for CD8+ T-cells against OPC when CD4+ T-cells are lost, but enhanced susceptibility to infection occurs when CD8+ T-cell migration is inhibited by reduced tissue E-cadherin. Objective Conduct a longitudinal study of tissue CD8+ T-cells and E-cadherin expression before, during, and after episodes of OPC. Methods Oral fungal burden was monitored and tissue was evaluated for CD8+ T-cells and E-cadherin over a one-year period in HIV+ persons with a history of, or an acute episode of OPC. Results While longitudinal analyses precluded formal interpretations, point prevalence analyses of the dataset revealed that when patients experiencing OPC were successfully treated, tissue E-cadherin expression was similar to patients who had not experienced OPC, and higher numbers of CD8+ T-cells were distributed throughout OPC− tissue under normal expression of E-cadherin. Conclusion These results suggest that 1) reduction in tissue E-cadherin expression in OPC+ patients is not permanent, and 2) high numbers of CD8+ T-cells can be distributed throughout OPC− tissue under normal E-cadherin expression. Together these results extend our previous studies and continue to support a role for CD8+ T-cells in host defense against OPC. PMID:21958417

  17. Potentiating the antitumour response of CD8+ T cells by modulating cholesterol metabolism

    Science.gov (United States)

    Yang, Wei; Bai, Yibing; Xiong, Ying; Zhang, Jin; Chen, Shuokai; Zheng, Xiaojun; Meng, Xiangbo; Li, Lunyi; Wang, Jing; Xu, Chenguang; Yan, Chengsong; Wang, Lijuan; Chang, Catharine C. Y.; Chang, Ta-Yuan; Zhang, Ti; Zhou, Penghui; Song, Bao-Liang; Liu, Wanli; Sun, Shao-cong; Liu, Xiaolong; Li, Bo-liang; Xu, Chenqi

    2016-01-01

    CD8+ T cells have a central role in antitumour immunity, but their activity is suppressed in the tumour microenvironment1–4. Reactivating the cytotoxicity of CD8+ T cells is of great clinical interest in cancer immunotherapy. Here we report a new mechanism by which the antitumour response of mouse CD8+ T cells can be potentiated by modulating cholesterol metabolism. Inhibiting cholesterol esterification in T cells by genetic ablation or pharmacological inhibition of ACAT1, a key cholesterol esterification enzyme5, led to potentiated effector function and enhanced proliferation of CD8+ but not CD4+ T cells. This is due to the increase in the plasma membrane cholesterol level of CD8+ T cells, which causes enhanced T-cell receptor clustering and signalling as well as more efficient formation of the immunological synapse. ACAT1-deficient CD8+ T cells were better than wild-type CD8+ T cells at controlling melanoma growth and metastasis in mice. We used the ACAT inhibitor avasimibe, which was previously tested in clinical trials for treating atherosclerosis and showed a good human safety profile6,7, to treat melanoma in mice and observed a good antitumour effect. A combined therapy of avasimibe plus an anti-PD-1 antibody showed better efficacy than monotherapies in controlling tumour progression. ACAT1, an established target for atherosclerosis, is therefore also a potential target for cancer immunotherapy. PMID:26982734

  18. CD8 Follicular T Cells Promote B Cell Antibody Class Switch in Autoimmune Disease.

    Science.gov (United States)

    Valentine, Kristen M; Davini, Dan; Lawrence, Travis J; Mullins, Genevieve N; Manansala, Miguel; Al-Kuhlani, Mufadhal; Pinney, James M; Davis, Jason K; Beaudin, Anna E; Sindi, Suzanne S; Gravano, David M; Hoyer, Katrina K

    2018-05-09

    CD8 T cells can play both a protective and pathogenic role in inflammation and autoimmune development. Recent studies have highlighted the ability of CD8 T cells to function as T follicular helper (Tfh) cells in the germinal center in the context of infection. However, whether this phenomenon occurs in autoimmunity and contributes to autoimmune pathogenesis is largely unexplored. In this study, we show that CD8 T cells acquire a CD4 Tfh profile in the absence of functional regulatory T cells in both the IL-2-deficient and scurfy mouse models. Depletion of CD8 T cells mitigates autoimmune pathogenesis in IL-2-deficient mice. CD8 T cells express the B cell follicle-localizing chemokine receptor CXCR5, a principal Tfh transcription factor Bcl6, and the Tfh effector cytokine IL-21. CD8 T cells localize to the B cell follicle, express B cell costimulatory proteins, and promote B cell differentiation and Ab isotype class switching. These data reveal a novel contribution of autoreactive CD8 T cells to autoimmune disease, in part, through CD4 follicular-like differentiation and functionality. Copyright © 2018 by The American Association of Immunologists, Inc.

  19. CD8+ T cell infiltration in breast and colon cancer: A histologic and statistical analysis.

    Directory of Open Access Journals (Sweden)

    James Ziai

    Full Text Available The prevalence of cytotoxic tumor infiltrating lymphocytes (TILs has demonstrated prognostic value in multiple tumor types. In particular, CD8 counts (in combination with CD3 and CD45RO have been shown to be superior to traditional UICC staging in colon cancer patients and higher total CD8 counts have been associated with better survival in breast cancer patients. However, immune infiltrate heterogeneity can lead to potentially significant misrepresentations of marker prevalence in routine histologic sections. We examined step sections of breast and colorectal cancer samples for CD8+ T cell prevalence by standard chromogenic immunohistochemistry to determine marker variability and inform practice of T cell biomarker assessment in formalin-fixed, paraffin-embedded (FFPE tissue samples. Stained sections were digitally imaged and CD8+ lymphocytes within defined regions of interest (ROI including the tumor and surrounding stroma were enumerated. Statistical analyses of CD8+ cell count variability using a linear model/ANOVA framework between patients as well as between levels within a patient sample were performed. Our results show that CD8+ T-cell distribution is highly homogeneous within a standard tissue sample in both colorectal and breast carcinomas. As such, cytotoxic T cell prevalence by immunohistochemistry on a single level or even from a subsample of biopsy fragments taken from that level can be considered representative of cytotoxic T cell infiltration for the entire tumor section within the block. These findings support the technical validity of biomarker strategies relying on CD8 immunohistochemistry.

  20. T-cell help permits memory CD8(+) T-cell inflation during cytomegalovirus latency.

    Science.gov (United States)

    Walton, Senta M; Torti, Nicole; Mandaric, Sanja; Oxenius, Annette

    2011-08-01

    CD4(+) T cells are implied to sustain CD8(+) T-cell responses during persistent infections. As CD4(+) T cells are often themselves antiviral effectors, they might shape CD8(+) T-cell responses via help or via controlling antigen load. We used persistent murine CMV (MCMV) infection to dissect the impact of CD4(+) T cells on virus-specific CD8(+) T cells, distinguishing between increased viral load in the absence of CD4(+) T cells and CD4(+) T-cell-mediated helper mechanisms. Absence of T-helper cells was associated with sustained lytic MCMV replication and led to a slow and gradual reduction of the size and function of the MCMV-specific CD8(+) T-cell pool. However, when virus replication was controlled in the absence of CD4(+) T cells, CD8(+) T-cell function was comparably impaired, but in addition CD8(+) T-cell inflation, a hallmark of CMV infection, was completely abolished. Thus, CD8(+) T-cell inflation during latent CMV infection is strongly dependent on CD4(+) T-cell helper functions, which can partially be compensated by ongoing lytic viral replication in the absence of CD4(+) T cells. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. CD8(+)NKT-like cells regulate the immune response by killing antigen-bearing DCs.

    Science.gov (United States)

    Wang, Chao; Liu, Xi; Li, Zhengyuan; Chai, Yijie; Jiang, Yunfeng; Wang, Qian; Ji, Yewei; Zhu, Zhongli; Wan, Ying; Yuan, Zhenglong; Chang, Zhijie; Zhang, Minghui

    2015-09-15

    CD1d-dependent NKT cells have been extensively studied; however, the function of CD8(+)NKT-like cells, which are CD1d-independent T cells with NK markers, remains unknown. Here, we report that CD1d-independent CD8(+)NKT-like cells, which express both T cell markers (TCRβ and CD3) and NK cell receptors (NK1.1, CD49b and NKG2D), are activated and significantly expanded in mice immunized with GFP-expressing dendritic cells. Distinct from CD1d-dependent NKT cells, CD8(+)NKT-like cells possess a diverse repertoire of TCRs and secrete high levels of IFN-gamma but not IL-4. CD8(+)NKT-like cell development is normal in CD1d(-/-) mice, which suggests that CD8(+)NKT-like cells undergo a unique development pathway that differs from iNKT cells. Further functional analyses show that CD8(+)NKT-like cells suppress T-cell responses through elimination of dendritic cells in an antigen-specific manner. Adoptive transfer of antigen-specific CD8(+)NKT-like cells into RIP-OVA mice prevented subsequent development of diabetes in the animals induced by activated OT-I CD8 T cells. Our study suggests that CD8(+)NKT-like cells can function as antigen-specific suppressive cells to regulate the immune response through killing antigen-bearing DCs. Antigen-specific down regulation may provide an active and precise method for constraining an excessive immune response and avoiding bypass suppression of necessary immune responses to other antigens.

  2. CD8+NKT-like cells regulate the immune response by killing antigen-bearing DCs

    Science.gov (United States)

    Wang, Chao; Liu, Xi; Li, Zhengyuan; Chai, Yijie; Jiang, Yunfeng; Wang, Qian; Ji, Yewei; Zhu, Zhongli; Wan, Ying; Yuan, Zhenglong; Chang, Zhijie; Zhang, Minghui

    2015-01-01

    CD1d-dependent NKT cells have been extensively studied; however, the function of CD8+NKT-like cells, which are CD1d-independent T cells with NK markers, remains unknown. Here, we report that CD1d-independent CD8+NKT-like cells, which express both T cell markers (TCRβ and CD3) and NK cell receptors (NK1.1, CD49b and NKG2D), are activated and significantly expanded in mice immunized with GFP-expressing dendritic cells. Distinct from CD1d-dependent NKT cells, CD8+NKT-like cells possess a diverse repertoire of TCRs and secrete high levels of IFN-gamma but not IL-4. CD8+NKT-like cell development is normal in CD1d−/− mice, which suggests that CD8+NKT-like cells undergo a unique development pathway that differs from iNKT cells. Further functional analyses show that CD8+NKT-like cells suppress T-cell responses through elimination of dendritic cells in an antigen-specific manner. Adoptive transfer of antigen-specific CD8+NKT-like cells into RIP-OVA mice prevented subsequent development of diabetes in the animals induced by activated OT-I CD8 T cells. Our study suggests that CD8+NKT-like cells can function as antigen-specific suppressive cells to regulate the immune response through killing antigen-bearing DCs. Antigen-specific down regulation may provide an active and precise method for constraining an excessive immune response and avoiding bypass suppression of necessary immune responses to other antigens. PMID:26369936

  3. CD3+CD8+CD161high Tc17 cells are depleted in HIV-infection

    DEFF Research Database (Denmark)

    Gaardbo, Julie Christine; Hartling, Hans Jakob; Thorsteinsson, Kristina

    2012-01-01

    CD8+ Tc17 cells with pro-inflammatory properties have only recently been acknowledged, and Tc17 cells in HIV-infection are undescribed. CD3+CD8+CD161 Tc17 cells and the production of Interleukin-17 were examined in untreated and treated HIV-infected patients, HIV-HCV co-infected patients...... and healthy controls. Depletion of CD3+CD8+CD161 Tc17 cells and diminished production of Interleukin-17 in HIV-infected patients was found. The level of Tc17 cells was associated with the level of the CD4+ count in treated patients....

  4. IL-4 and IL-13 mediated down-regulation of CD8 expression levels can dampen anti-viral CD8⁺ T cell avidity following HIV-1 recombinant pox viral vaccination.

    Science.gov (United States)

    Wijesundara, Danushka K; Jackson, Ronald J; Tscharke, David C; Ranasinghe, Charani

    2013-09-23

    We have shown that mucosal HIV-1 recombinant pox viral vaccination can induce high, avidity HIV-specific CD8(+) T cells with reduced interleukin (IL)-4 and IL-13 expression compared to, systemic vaccine delivery. In the current study how these cytokines act to regulate anti-viral CD8(+) T, cell avidity following HIV-1 recombinant pox viral prime-boost vaccination was investigated. Out of a panel of T cell avidity markers tested, only CD8 expression levels were found to be enhanced on, KdGag197-205 (HIV)-specific CD8(+) T cells obtained from IL-13(-/-), IL-4(-/-) and signal transducer and, activator of transcription of 6 (STAT6)(-/-) mice compared to wild-type (WT) controls following, vaccination. Elevated CD8 expression levels in this instance also correlated with polyfunctionality, (interferon (IFN)-γ, tumour necorsis factor (TNF)-α and IL-2 production) and the avidity of HIVspecific CD8(+) T cells. Furthermore, mucosal vaccination and vaccination with the novel adjuvanted IL-13 inhibitor (i.e. IL-13Rα2) vaccines significantly enhanced CD8 expression levels on HIV-specific CD8(+), T cells, which correlated with avidity. Using anti-CD8 antibodies that blocked CD8 availability on CD8(+), T cells, it was established that CD8 played an important role in increasing HIV-specific CD8(+) T cell avidity and polyfunctionality in IL-4(-/-), IL-13(-/-) and STAT6(-/-) mice compared to WT controls, following vaccination. Collectively, our data demonstrate that IL-4 and IL-13 dampen CD8 expression levels on anti-viral CD8(+) T cells, which can down-regulate anti-viral CD8(+) T cell avidity and, polyfunctionality following HIV-1 recombinant pox viral vaccination. These findings can be exploited to, design more efficacious vaccines not only against HIV-1, but many chronic infections where high, avidity CD8(+) T cells help protection. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Correlation of Increases in 1,25-Dihydroxyvitamin D During Vitamin D Therapy With Activation of CD4+ T Lymphocytes in HIV-1-Infected Males

    DEFF Research Database (Denmark)

    Bang, Ulrich; Kolte, Lilian; Hitz, Mette

    2012-01-01

    = .01) in adjusted models. Changes in parathyroid hormone correlated inversely with Tregs (P = .02). Smokers had higher levels of naïve CD4+ T lymphocytes (37% vs 25%;P = .01), naïve CD8+ T lymphocytes (28% vs 19%; P = .03), and Tregs (9% vs 7%; P = .03). Conclusion: Cholecalciferol and calcitriol...

  6. Acetyl CoA Carboxylase 2 Is Dispensable for CD8+ T Cell Responses.

    Directory of Open Access Journals (Sweden)

    Jang Eun Lee

    Full Text Available Differentiation of T cells is closely associated with dynamic changes in nutrient and energy metabolism. However, the extent to which specific metabolic pathways and molecular components are determinative of CD8+ T cell fate remains unclear. It has been previously established in various tissues that acetyl CoA carboxylase 2 (ACC2 regulates fatty acid oxidation (FAO by inhibiting carnitine palmitoyltransferase 1 (CPT1, a rate-limiting enzyme of FAO in mitochondria. Here, we explore the cell-intrinsic role of ACC2 in T cell immunity in response to infections. We report here that ACC2 deficiency results in a marginal increase of cellular FAO in CD8+ T cells, but does not appear to influence antigen-specific effector and memory CD8+ T cell responses during infection with listeria or lymphocytic choriomeningitis virus. These results suggest that ACC2 is dispensable for CD8+ T cell responses.

  7. Role of CD5-negative CD8 T Cells in Adaptation to Antigenic ...

    African Journals Online (AJOL)

    Plasma HIV-1 load was measured by Versant™ ... process leads to substantial progress in the .... cells/µl/month in patients with baseline viral load ... in blood CD8+ T cell count during anolignan A treatment using logistic regression models.

  8. The CD4+/CD8+ Ratio in Pulmonary Tuberculosis: Systematic and Meta-Analysis Article.

    Science.gov (United States)

    Yin, Yongmei; Qin, Jie; Dai, Yaping; Zeng, Fanwei; Pei, Hao; Wang, Jun

    2015-02-01

    The ratio of CD4+/CD8+ has been used as a clinically index to evaluate patients' immunity. Numerous researchers have studied CD4+/CD8+ ratio in pulmonary tuberculosis (PTB) patients. However, the change of CD4+/CD8+ ratio remains controversial. We present a meta-analysis of 15 case-control studies to identify the change of CD4+/CD8+ ratio in PTB patients. We assessed heterogeneity of effect estimates within each group using I(2) test. Subgroup analysis was performed to explore the potential source of heterogeneity. To investigate further the potential publication bias, we visually examined the funnel plots. For robustness of results, we performed sensitivity analysis by removing studies. Data entry and analyses were carried out with RevMan 5.2 (The Nordic Cochrane Centre). Twelve peripheral blood studies were categorized into two subgroups. Eight studies presented a significant decrease of CD4+/CD8+ ratio in PTB cases compared to healthy subjects (SMD: -0.45; 95% CI -0.65--0.25; I(2) = 7%). Other four studies researched on the newly diagnosed patients presented a more seriously and significantly decrease (SMD: -2.17; 95% CI -2.61--1.74; I(2) = 37%). The pooled analysis of bronchoalveolar lavage fluid (BALF) studies showed a significant increase of CD4+/CD8+ ratio using Flow Cytometry (FCM) (SMD: 4.75; 95% CI 3.44-6.05; I(2) =0%). The present meta-analysis indicated that there was a synthetic evidence for the reduced CD4+/CD8+ ratio in peripheral blood of PTB patients, especially newly diagnosed cases. However, the CD4+/CD8+ ratio in BALF was increased using method of FCM.

  9. Mycobacterium tuberculosis specific CD8(+ T cells rapidly decline with antituberculosis treatment.

    Directory of Open Access Journals (Sweden)

    Melissa R Nyendak

    Full Text Available Biomarkers associated with response to therapy in tuberculosis could have broad clinical utility. We postulated that the frequency of Mycobacterium tuberculosis (Mtb specific CD8(+ T cells, by virtue of detecting intracellular infection, could be a surrogate marker of response to therapy and would decrease during effective antituberculosis treatment.We sought to determine the relationship of Mtb specific CD4(+ T cells and CD8(+ T cells with duration of antituberculosis treatment.We performed a prospective cohort study, enrolling between June 2008 and August 2010, of HIV-uninfected Ugandan adults (n = 50 with acid-fast bacillus smear-positive, culture confirmed pulmonary TB at the onset of antituberculosis treatment and the Mtb specific CD4(+ and CD8(+ T cell responses to ESAT-6 and CFP-10 were measured by IFN-γ ELISPOT at enrollment, week 8 and 24.There was a significant difference in the Mtb specific CD8(+ T response, but not the CD4(+ T cell response, over 24 weeks of antituberculosis treatment (p<0.0001, with an early difference observed at 8 weeks of therapy (p = 0.023. At 24 weeks, the estimated Mtb specific CD8(+ T cell response decreased by 58%. In contrast, there was no significant difference in the Mtb specific CD4(+ T cell during the treatment. The Mtb specific CD4(+ T cell response, but not the CD8(+ response, was negatively impacted by the body mass index.Our data provide evidence that the Mtb specific CD8(+ T cell response declines with antituberculosis treatment and could be a surrogate marker of response to therapy. Additional research is needed to determine if the Mtb specific CD8(+ T cell response can detect early treatment failure, relapse, or to predict disease progression.

  10. T helper-independent activation of human CD8+ cells: the role of CD28 costimulation.

    Science.gov (United States)

    Van Gool, S W; Zhang, Y; Kasran, A; de Boer, M; Ceuppens, J L

    1996-07-01

    The concept that activation of MHC class I-restricted CD8+ cells entirely depends on help from MHC class II-restricted CD4+ T cells has recently been supplemented with an alternative model in which CD8+ cells can directly be activated by MHC class I-expressing professional antigen-presenting cells (APC), which are able to deliver an accessory signal. The authors analysed the role of CD28-mediated costimulation for T helper cell-independent activation of purified human CD8+ T cells in two different in vitro models. Freshly isolated CD8+ cells could be activated (proliferation, IL-2 production and cytotoxic activity) by anti-CD3-presenting Fc gamma R+ mouse cells transfected with the human CD28 ligand, CD80, as the only accessory signal. On the other hand, activation of CD8+ cells by allogeneic MHC class I on EBV-transformed B cells, which express two different CD28 ligands, CD80 and CD86, also proceeded very efficiently (proliferation, cytotoxic activity and CD25 expression), but was either not, or only partially, blocked by anti-CD80 and anti-CD86 MoAb or CTLA-4Ig. This indicates that other costimulatory signals are also effective, and that CD28 triggering is not absolutely required for initial T-cell activation. CsA and CD80/CD86-blocking agents were synergistic in completely inhibiting activation of CD8+ cells in the MLR with allogeneic B-cell lines. This combination also induced non-responsiveness of CD8+ cells upon restimulation in the absence of blocking agents. Therefore, although professional APC can apparently provide multiple costimulatory signals for direct activation of CD8+ T cells, the signal derived from CD80/CD86 is unique in providing CsA-resistance.

  11. Measuring the diaspora for virus-specific CD8+ T cells

    Science.gov (United States)

    Marshall, Dana R.; Turner, Stephen J.; Belz, Gabrielle T.; Wingo, Suzette; Andreansky, Samita; Sangster, Mark Y.; Riberdy, Janice M.; Liu, Tiebin; Tan, Ming; Doherty, Peter C.

    2001-01-01

    The CD8+ T cell diaspora has been analyzed after secondary challenge with an influenza A virus that replicates only in the respiratory tract. Numbers of DbNP366- and DbPA224-specific CD8+ T cells were measured by tetramer staining at the end of the recall response, then followed sequentially in the lung, lymph nodes, spleen, blood, and other organs. The extent of clonal expansion did not reflect the sizes of the preexisting memory T cell pools. Although the high-frequency CD8+ tetramer+ populations in the pneumonic lung and mediastinal lymph nodes fell rapidly from peak values, the “whole mouse” virus-specific CD8+ T cell counts decreased only 2-fold over the 4 weeks after infection, then subsided at a fairly steady rate to reach a plateau at about 2 months. The largest numbers were found throughout in the spleen, then the bone marrow. The CD8+DbNP366+ and CD8+DbPA224+ sets remained significantly enlarged for at least 4 months, declining at equivalent rates while retaining the nucleoprotein > acid polymerase immunodominance hierarchy characteristic of the earlier antigen-driven phase. Lowest levels of the CD69 “activation marker” were detected consistently on virus-specific CD8+ T cells in the blood, then the spleen. Those in the bone marrow and liver were intermediate, and CD69hi T cells were very prominent in the regional lymph nodes and the nasal-associated lymphoid tissue. Any population of “resting” CD8+ memory T cells is thus phenotypically heterogeneous, widely dispersed, and subject to broad homeostatic and local environmental effects irrespective of epitope specificity or magnitude. PMID:11344265

  12. Systemic immunological tolerance to ocular antigens is mediated by TRAIL-expressing CD8+ T cells.

    Science.gov (United States)

    Griffith, Thomas S; Brincks, Erik L; Gurung, Prajwal; Kucaba, Tamara A; Ferguson, Thomas A

    2011-01-15

    Systemic immunological tolerance to Ag encountered in the eye restricts the formation of potentially damaging immune responses that would otherwise be initiated at other anatomical locations. We previously demonstrated that tolerance to Ag administered via the anterior chamber (AC) of the eye required Fas ligand-mediated apoptotic death of inflammatory cells that enter the eye in response to the antigenic challenge. Moreover, the systemic tolerance induced after AC injection of Ag was mediated by CD8(+) regulatory T cells. This study examined the mechanism by which these CD8(+) regulatory T cells mediate tolerance after AC injection of Ag. AC injection of Ag did not prime CD4(+) T cells and led to increased TRAIL expression by splenic CD8(+) T cells. Unlike wild-type mice, Trail(-/-) or Dr5(-/-) mice did not develop tolerance to Ag injected into the eye, even though responding lymphocytes underwent apoptosis in the AC of the eyes of these mice. CD8(+) T cells from Trail(-/-) mice that were first injected via the AC with Ag were unable to transfer tolerance to naive recipient wild-type mice, but CD8(+) T cells from AC-injected wild-type or Dr5(-/-) mice could transfer tolerance. Importantly, the transferred wild-type (Trail(+/+)) CD8(+) T cells were also able to decrease the number of infiltrating inflammatory cells into the eye; however, Trail(-/-) CD8(+) T cells were unable to limit the inflammatory cell ingress. Together, our data suggest that "helpless" CD8(+) regulatory T cells generated after AC injection of Ag enforce systemic tolerance in a TRAIL-dependent manner to inhibit inflammation in the eye.

  13. Memory CD8 T cells mediate severe immunopathology following respiratory syncytial virus infection.

    Directory of Open Access Journals (Sweden)

    Megan E Schmidt

    2018-01-01

    Full Text Available Memory CD8 T cells can provide protection from re-infection by respiratory viruses such as influenza and SARS. However, the relative contribution of memory CD8 T cells in providing protection against respiratory syncytial virus (RSV infection is currently unclear. To address this knowledge gap, we utilized a prime-boost immunization approach to induce robust memory CD8 T cell responses in the absence of RSV-specific CD4 T cells and antibodies. Unexpectedly, RSV infection of mice with pre-existing CD8 T cell memory led to exacerbated weight loss, pulmonary disease, and lethal immunopathology. The exacerbated disease in immunized mice was not epitope-dependent and occurred despite a significant reduction in RSV viral titers. In addition, the lethal immunopathology was unique to the context of an RSV infection as mice were protected from a normally lethal challenge with a recombinant influenza virus expressing an RSV epitope. Memory CD8 T cells rapidly produced IFN-γ following RSV infection resulting in elevated protein levels in the lung and periphery. Neutralization of IFN-γ in the respiratory tract reduced morbidity and prevented mortality. These results demonstrate that in contrast to other respiratory viruses, RSV-specific memory CD8 T cells can induce lethal immunopathology despite mediating enhanced viral clearance.

  14. CD4+ T cell effects on CD8+ T cell location defined using bioluminescence.

    Directory of Open Access Journals (Sweden)

    Mitra Azadniv

    2011-01-01

    Full Text Available T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are "helped" by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell "help" is to program the homing potential of CD8+ T cells.

  15. Neonatal CD8+ T-cell differentiation is dependent on interleukin-12.

    LENUS (Irish Health Repository)

    McCarron, Mark J

    2012-02-01

    Neonatal CD8(+) T-cell activation is significantly impaired compared with that in adults. Recent studies have demonstrated that interleukin (IL)-12 is necessary as a third signal, in addition to antigen and co-stimulation, to authorize the differentiation of naive CD8(+) T cells. We examined whether human neonatal CD8(+) T cells, which possess an exclusively naive T-cell phenotype, required a third signal to authorize a productive T-cell response. IL-12 enhanced activated naive CD8(+) T-cell survival, expansion, CD25 expression, and IL-2 production. Activated CD8(+) T cells produced interferon-gamma and intracellular granzyme B and were cytotoxic only in the presence of IL-12. Sustained IL-12 signaling for 72 hours was required for optimal interferon-gamma production. IL-12, in concert with T cell receptor (TCR) stimulation, sustained late-stage (48-72 hours) intracellular phosphorylation and particularly total protein levels of the proximal TCR components, Lck, and CD3xi. The requirement for a third signal for productive human neonatal CD8(+) T-cell differentiation may have implications for neonatal vaccination strategies.

  16. Tumor-Induced CD8+ T-Cell Dysfunction in Lung Cancer Patients

    Directory of Open Access Journals (Sweden)

    Heriberto Prado-Garcia

    2012-01-01

    Full Text Available Lung cancer is the leading cause of cancer deaths worldwide and one of the most common types of cancers. The limited success of chemotherapy and radiotherapy regimes have highlighted the need to develop new therapies like antitumor immunotherapy. CD8+ T-cells represent a major arm of the cell-mediated anti-tumor response and a promising target for developing T-cell-based immunotherapies against lung cancer. Lung tumors, however, have been considered to possess poor immunogenicity; even so, lung tumor-specific CD8+ T-cell clones can be established that possess cytotoxicity against autologous tumor cells. This paper will focus on the alterations induced in CD8+ T-cells by lung cancer. Although memory CD8+ T-cells infiltrate lung tumors, in both tumor-infiltrating lymphocytes (TILs and malignant pleural effusions, these cells are dysfunctional and the effector subset is reduced. We propose that chronic presence of lung tumors induces dysfunctions in CD8+ T-cells and sensitizes them to activation-induced cell death, which may be associated with the poor clinical responses observed in immunotherapeutic trials. Getting a deeper knowledge of the evasion mechanisms lung cancer induce in CD8+ T-cells should lead to further understanding of lung cancer biology, overcome tumor evasion mechanisms, and design improved immunotherapeutic treatments for lung cancer.

  17. Distinctive CD8+ T cell and MHC class I signatures in polycythemia vera patients.

    Science.gov (United States)

    Cardoso, Elsa M; Esgalhado, André J; Patrão, Luís; Santos, Mónica; Neves, Vasco Pinto; Martinez, Jorge; Patto, Maria Assunção Vaz; Silva, Helena; Arosa, Fernando A

    2018-05-22

    Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by overproduction of red blood cells. We have performed a comprehensive characterization of blood immune cells for expression of naïve and memory receptors as well as β 2 m-associated and β 2 m-free MHC class I heavy chains, also known as closed and open conformers, respectively, in PV patients and age-matched controls (CTR). We show that the peripheral CD3 + CD8 + T cell pool in PV patients is clearly divided into two discrete populations, a more granular CD3 + CD8 high T cell population enriched in effector-memory CD45RA + T cells (CD8 + TEMRA) when compared to CTR (P e., CD3 + CD8 int CD28 int . While the percentage of CD3 + CD8 int TN cells correlated positively with the number of erythrocytes, the percentage of CD3 + CD8 int TEMRA correlated negatively with the number of platelets. Finally, we report that PV patients' lymphocytes and monocytes display lower levels of closed (W6/32 + ) MHC-I conformers at the cell surface while exhibiting increased amounts of open (HC-10 + ) MHC-I conformers. The implications of this distinctive immune signature are discussed.

  18. Increased Aqueous Humor CD4+/CD8+ Lymphocyte Ratio in Sarcoid Uveitis.

    Science.gov (United States)

    Dave, Namita; Chevour, Priyanka; Mahendradas, Padmamalini; Venkatesh, Anitha; Kawali, Ankush; Shetty, Rohit; Ghosh, Arkasubhra; Sethu, Swaminathan

    2018-02-08

    To determine aqueous humor CD4+/CD8+ T-lymphocyte ratio changes in sarcoid and non-sarcoid uveitis with anterior chamber involvement. The case-control study includes 61 patients with either anterior uveitis, intermediate uveitis with anterior spill, or panuveitis. A total of 21 of them were categorized as sarcoid uveitis and 40 as non-sarcoid uveitis according to diagnostic criteria. CD4+/CD8+ ratio in the aqueous humor was determined using flow cytometry. Significantly higher CD4+/CD8+ ratio in the aqueous humor was observed in patients with sarcoid uveitis (6.3 ± 1.4; mean ± SEM) compared to non-sarcoid uveitis (1.6 ± 0.1; mean ± SEM). Whole blood CD4+/CD8+ ratio was not elevated in subjects with sarcoid and non-sarcoid uveitis. Aqueous humor CD4+/CD8+ ratio >3.5 was observed to be associated with sarcoid uveitis (OR 38, 95% CI 7.0-205.2). Increased aqueous humor CD4+/CD8+ ratio in sarcoid uveitis. Immunophenotyping of localized lymphocytosis in aqueous humor could be utilized as an additional confirmatory marker for ocular sarcoidosis.

  19. IL-17-Expressing CD4+ and CD8+ T Lymphocytes in Human Toxoplasmosis

    Directory of Open Access Journals (Sweden)

    Jéssica Líver Alves Silva

    2014-01-01

    Full Text Available This study aimed to measure the synthesis of Th1 and Th2 cytokines by mononuclear cells after culture with live T. gondii and identified Th17 (CD4+ and Tc17 (CD8+ cells in toxoplasma-seronegative and toxoplasma-seropositive parturient and nonpregnant women. Cytometric bead arrays were used to measure cytokine levels (IL-2, TNF-α, IFN-γ, IL-4, IL-5, and IL-10; immunophenotyping was used to characterize Th17 and Tc17 cells, and the cells were stained with antibodies against CD4+ and CD8+ T cells expressing IL-17. The addition of tachyzoites to cell cultures induced the synthesis of IL-5, IL-10, and TNF-α by cells from seronegative parturient women and of IL-5 and IL-10 by cells from seropositive, nonpregnant women. We observed a lower level of IL-17-expressing CD4+ and CD8+ T lymphocytes in cultures of cells from seronegative and seropositive parturient and nonpregnant women that were stimulated with tachyzoites, whereas analysis of the CD4+ and CD8+ T cell populations showed a higher level of CD4+ T cells compared with CD8+ T cells. These results suggest that the cytokine pattern and IL-17-expressing CD4+ and CD8+ T lymphocytes may have important roles in the inflammatory response to T. gondii, thus contributing to the maintenance of pregnancy and control of parasite invasion and replication.

  20. Immune Checkpoint Function of CD85j in CD8 T Cell Differentiation and Aging

    Directory of Open Access Journals (Sweden)

    Claire E. Gustafson

    2017-06-01

    Full Text Available Aging is associated with an increased susceptibility to infection and a failure to control latent viruses thought to be driven, at least in part, by alterations in CD8 T cell function. The aging T cell repertoire is characterized by an accumulation of effector CD8 T cells, many of which express the negative regulatory receptor CD85j. To define the biological significance of CD85j expression on CD8 T cells and to address the question whether presence of CD85j in older individuals is beneficial or detrimental for immune function, we examined the specific attributes of CD8 T cells expressing CD85j as well as the functional role of CD85j in antigen-specific CD8 T cell responses during immune aging. Here, we show that CD85j is mainly expressed by terminally differentiated effector (TEMRAs CD8 T cells, which increase with age, in cytomegalovirus (CMV infection and in males. CD85j+ CMV-specific cells demonstrate clonal expansion. However, TCR diversity is similar between CD85j+ and CD85j− compartments, suggesting that CD85j does not directly impact the repertoire of antigen-specific cells. Further phenotypic and functional analyses revealed that CD85j identifies a specific subset of CMV-responsive CD8 T cells that coexpress a marker of senescence (CD57 but retain polyfunctional cytokine production and expression of cytotoxic mediators. Blocking CD85j binding enhanced proliferation of CMV-specific CD8 T cells upon antigen stimulation but did not alter polyfunctional cytokine production. Taken together, these data demonstrate that CD85j characterizes a population of “senescent,” but not exhausted antigen-specific effector CD8 T cells and indicates that CD85j is an important checkpoint regulator controlling expansion of virus-specific T cells during aging. Inhibition of CD85j activity may be a mechanism to promote stronger CD8 T cell effector responses during immune aging.

  1. Phenotypic and Functional Alterations in Circulating Memory CD8 T Cells with Time after Primary Infection.

    Directory of Open Access Journals (Sweden)

    Matthew D Martin

    2015-10-01

    Full Text Available Memory CD8 T cells confer increased protection to immune hosts upon secondary viral, bacterial, and parasitic infections. The level of protection provided depends on the numbers, quality (functional ability, and location of memory CD8 T cells present at the time of infection. While primary memory CD8 T cells can be maintained for the life of the host, the full extent of phenotypic and functional changes that occur over time after initial antigen encounter remains poorly characterized. Here we show that critical properties of circulating primary memory CD8 T cells, including location, phenotype, cytokine production, maintenance, secondary proliferation, secondary memory generation potential, and mitochondrial function change with time after infection. Interestingly, phenotypic and functional alterations in the memory population are not due solely to shifts in the ratio of effector (CD62Llo and central memory (CD62Lhi cells, but also occur within defined CD62Lhi memory CD8 T cell subsets. CD62Lhi memory cells retain the ability to efficiently produce cytokines with time after infection. However, while it is was not formally tested whether changes in CD62Lhi memory CD8 T cells over time occur in a cell intrinsic manner or are due to selective death and/or survival, the gene expression profiles of CD62Lhi memory CD8 T cells change, phenotypic heterogeneity decreases, and mitochondrial function and proliferative capacity in either a lymphopenic environment or in response to antigen re-encounter increase with time. Importantly, and in accordance with their enhanced proliferative and metabolic capabilities, protection provided against chronic LCMV clone-13 infection increases over time for both circulating memory CD8 T cell populations and for CD62Lhi memory cells. Taken together, the data in this study reveal that memory CD8 T cells continue to change with time after infection and suggest that the outcome of vaccination strategies designed to elicit

  2. CD8{sup +}CD25{sup +} T cells reduce atherosclerosis in apoE(−/−) mice

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jianchang; Dimayuga, Paul C.; Zhao, Xiaoning; Yano, Juliana; Lio, Wai Man; Trinidad, Portia; Honjo, Tomoyuki; Cercek, Bojan; Shah, Prediman K.; Chyu, Kuang-Yuh, E-mail: Chyuk@cshs.org

    2014-01-17

    Highlights: •The role of a sub-population of CD8{sup +} T cells with suppressor functions was investigated in atherosclerosis. •CD8{sup +}CD25{sup +} T cells from adult apoE(−/−) mice had phenotype characteristics of T suppressor cells. •These CD8{sup +}CD25{sup +} T cells reduced CD4{sup +} T cell proliferation and CD8{sup +} cytotoxic activity in vitro. •Adoptive transfer of CD8{sup +}CD25{sup +} T cells significantly reduced atherosclerosis. •CD8{sup +}CD25{sup +} T cells have a suppressive function in atherosclerosis. -- Abstract: Background: It is increasingly evident that CD8{sup +} T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8{sup +}CD25{sup +} T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis were investigated in this study. Methods and results: CD8{sup +}CD25{sup +} T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8{sup +}CD25{sup +} T cells from apoE(−/−) mice. Depletion of CD8{sup +}CD25{sup +} from total CD8{sup +} T cells rendered higher cytolytic activity of the remaining CD8{sup +}CD25{sup −} T cells. Adoptive transfer of CD8{sup +}CD25{sup +} T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4{sup +} T cells and significantly reduced atherosclerosis in recipient mice. Conclusions: Our study has identified an athero-protective role for CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis.

  3. Alternative pathway for the development of Vα14+ NKT cells directly from CD4-CD8- thymocytes that bypasses the CD4+CD8+ stage.

    Science.gov (United States)

    Dashtsoodol, Nyambayar; Shigeura, Tomokuni; Aihara, Minako; Ozawa, Ritsuko; Kojo, Satoshi; Harada, Michishige; Endo, Takaho A; Watanabe, Takashi; Ohara, Osamu; Taniguchi, Masaru

    2017-03-01

    Although invariant V α 14 + natural killer T cells (NKT cells) are thought to be generated from CD4 + CD8 + double-positive (DP) thymocytes, the developmental origin of CD4 - CD8 - double-negative (DN) NKT cells still remains unresolved. Here we provide definitive genetic evidence obtained, through studies of mice with DP-stage-specific ablation of expression of the gene encoding the recombinase component RAG-2 (Rag2) and by a fate-mapping approach, that supports the proposal of the existence of an alternative developmental pathway through which a fraction of DN NKT cells with strong T-helper-type-1 (T H 1)-biased and cytotoxic characteristics develop from late DN-stage thymocytes, bypassing the DP stage. These findings provide new insight into understanding of the development of NKT cells and propose a role for timing of expression of the invariant T cell antigen receptor in determining the functional properties of NKT cells.

  4. HIV-Specific CD8+ T Cell-Mediated Viral Suppression Correlates With the Expression of CD57

    DEFF Research Database (Denmark)

    Jensen, Sanne S; Tingstedt, Jeanette Linnea; Larsen, Tine Kochendorf

    2016-01-01

    BACKGROUND: Virus-specific CD8(+) T-cell responses are believed to play an important role in the control of HIV-1 infection; however, what constitutes an effective HIV-1 CD8(+) T-cell response remains a topic of debate. The ex vivo viral suppressive capacity was measured of CD8(+) T cells from 44...

  5. Radiation-induced decrease of CD8+ dendritic cells contributes to Th1/Th2 shift.

    Science.gov (United States)

    Liu, Hu; Li, Bailong; Jia, Xiaojing; Ma, Yan; Gu, Yifeng; Zhang, Pei; Wei, Qun; Cai, Jianming; Cui, Jianguo; Gao, Fu; Yang, Yanyong

    2017-05-01

    Exposure to ionizing radiation (IR) often reduce the helper T (Th) 1 like function, resulting in a Th1/Th2 imbalance, which could affect the efficacy of cancer radiotherapy. As the most potent antigen presenting cells, dendritic cells (DC) can be divided into several subsets with specialized function. However, there is no literature covering the changes of DC subsets and their roles in immune regulation in response to IR. In the present study, we were aimed to investigate the changes of DC subsets after IR and its relationship with Th1/Th2 immunity. We found a significant decrease of BDCA3+DC in the blood of patients treated with radiotherapy. CD8+DC, a mouse equivalent of human BDCA3+DC, was also found decreased in mice spleen, peripheral blood and lymph node tissues after irradiation. As CD8+DC mainly induce Th1 immunity, we tested the changes of Th1/Th2 response and found that IR caused a repression of Th1 immunity, indicating a possible role of CD8+DC in radiation-induced Th1/Th2 imbalance. We also found that a CD8+DC-inducing cytokine, Fms-like tyrosine kinase 3 ligand (FLT3 ligand), restored CD8+DC and reversed Th1/Th2 shift. And then we found that bone marrow cells from irradiated mice differentiated into less CD8+DC, which was also protected by FLT3 ligand. In conclusion, our data showed that IR induced a decrease of CD8+DC and Th1/Th2 shift, which was reversed by Flt3 ligand treatment, suggesting a novel mechanism for radiation-induced immunosuppression. Copyright © 2017. Published by Elsevier B.V.

  6. CD8 Memory Cells Develop Unique DNA Repair Mechanisms Favoring Productive Division.

    Science.gov (United States)

    Galgano, Alessia; Barinov, Aleksandr; Vasseur, Florence; de Villartay, Jean-Pierre; Rocha, Benedita

    2015-01-01

    Immune responses are efficient because the rare antigen-specific naïve cells are able to proliferate extensively and accumulate upon antigen stimulation. Moreover, differentiation into memory cells actually increases T cell accumulation, indicating improved productive division in secondary immune responses. These properties raise an important paradox: how T cells may survive the DNA lesions necessarily induced during their extensive division without undergoing transformation. We here present the first data addressing the DNA damage responses (DDRs) of CD8 T cells in vivo during exponential expansion in primary and secondary responses in mice. We show that during exponential division CD8 T cells engage unique DDRs, which are not present in other exponentially dividing cells, in T lymphocytes after UV or X irradiation or in non-metastatic tumor cells. While in other cell types a single DDR pathway is affected, all DDR pathways and cell cycle checkpoints are affected in dividing CD8 T cells. All DDR pathways collapse in secondary responses in the absence of CD4 help. CD8 T cells are driven to compulsive suicidal divisions preventing the propagation of DNA lesions. In contrast, in the presence of CD4 help all the DDR pathways are up regulated, resembling those present in metastatic tumors. However, this up regulation is present only during the expansion phase; i.e., their dependence on antigen stimulation prevents CD8 transformation. These results explain how CD8 T cells maintain genome integrity in spite of their extensive division, and highlight the fundamental role of DDRs in the efficiency of CD8 immune responses.

  7. Ikaros imposes a barrier to CD8+ T cell differentiation by restricting autocrine IL-2 production.

    Science.gov (United States)

    O'Brien, Shaun; Thomas, Rajan M; Wertheim, Gerald B; Zhang, Fuqin; Shen, Hao; Wells, Andrew D

    2014-06-01

    Naive CD4(+) T cells require signals from the TCR and CD28 to produce IL-2, expand, and differentiate. However, these same signals are not sufficient to induce autocrine IL-2 production by naive CD8(+) T cells, which require cytokines provided by other cell types to drive their differentiation. The basis for failed autocrine IL-2 production by activated CD8(+) cells is unclear. We find that Ikaros, a transcriptional repressor that silences IL-2 in anergic CD4(+) T cells, also restricts autocrine IL-2 production by CD8(+) T cells. We find that CD8(+) T cell activation in vitro in the absence of exogenous cytokines and CD4 help leads to marked induction of Ikaros, a known repressor of the Il2 gene. Naive murine CD8 T cells haplo-insufficient for Ikzf1 failed to upregulate Ikaros, produced autocrine IL-2, and differentiated in an IL-2-dependent manner into IFN-γ-producing CTLs in response to TCR/CD28 stimulation alone. Furthermore, Ikzf1 haplo-insufficient CD8(+) T cells were more effective at controlling Listeria infection and B16 melanoma growth in vivo, and they could provide help to neighboring, non-IL-2-producing cells to differentiate into IFN-γ-producing effectors. Therefore, by repressing autocrine IL-2 production, Ikaros ensures that naive CD8(+) T cells remain dependent on licensing by APCs and CD4(+) T cells, and it may therefore act as a cell-intrinsic safeguard against inappropriate CTL differentiation and immunopathology. Copyright © 2014 by The American Association of Immunologists, Inc.

  8. Attrition of memory CD8 T cells during sepsis requires LFA-1.

    Science.gov (United States)

    Serbanescu, Mara A; Ramonell, Kimberly M; Hadley, Annette; Margoles, Lindsay M; Mittal, Rohit; Lyons, John D; Liang, Zhe; Coopersmith, Craig M; Ford, Mandy L; McConnell, Kevin W

    2016-11-01

    CD8 T cell loss and dysfunction have been implicated in the increased susceptibility to opportunistic infections during the later immunosuppressive phase of sepsis, but CD8 T cell activation and attrition in early sepsis remain incompletely understood. With the use of a CLP model, we assessed CD8 T cell activation at 5 consecutive time points and found that activation after sepsis results in a distinct phenotype (CD69 + CD25 int CD62L HI ) independent of cognate antigen recognition and TCR engagement and likely through bystander-mediated cytokine effects. Additionally, we observed that sepsis concurrently results in the preferential depletion of a subset of memory-phenotype CD8 T cells that remain "unactivated" (i.e., fail to up-regulate activation markers) by apoptosis. Unactivated CD44 HI OT-I cells were spared from sepsis-induced attrition, as were memory-phenotype CD8 T cells of mice treated with anti-LFA-1 mAb, 1 h after CLP. Perhaps most importantly, we demonstrate that attrition of memory phenotype cells may have a pathologic significance, as elevated IL-6 levels were associated with decreased numbers of memory-phenotype CD8 T cells in septic mice, and preservation of this subset after administration of anti-LFA-1 mAb conferred improved survival at 7 d. Taken together, these data identify potentially modifiable responses of memory-phenotype CD8 T cells in early sepsis and may be particularly important in the application of immunomodulatory therapies in sepsis. © Society for Leukocyte Biology.

  9. CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

    Directory of Open Access Journals (Sweden)

    Andréia Manso de Matos

    2015-02-01

    Full Text Available Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population.

  10. Human memory CD8 T cell effector potential is epigenetically preserved during in vivo homeostasis.

    Science.gov (United States)

    Abdelsamed, Hossam A; Moustaki, Ardiana; Fan, Yiping; Dogra, Pranay; Ghoneim, Hazem E; Zebley, Caitlin C; Triplett, Brandon M; Sekaly, Rafick-Pierre; Youngblood, Ben

    2017-06-05

    Antigen-independent homeostasis of memory CD8 T cells is vital for sustaining long-lived T cell-mediated immunity. In this study, we report that maintenance of human memory CD8 T cell effector potential during in vitro and in vivo homeostatic proliferation is coupled to preservation of acquired DNA methylation programs. Whole-genome bisulfite sequencing of primary human naive, short-lived effector memory (T EM ), and longer-lived central memory (T CM ) and stem cell memory (T SCM ) CD8 T cells identified effector molecules with demethylated promoters and poised for expression. Effector-loci demethylation was heritably preserved during IL-7- and IL-15-mediated in vitro cell proliferation. Conversely, cytokine-driven proliferation of T CM and T SCM memory cells resulted in phenotypic conversion into T EM cells and was coupled to increased methylation of the CCR7 and Tcf7 loci. Furthermore, haploidentical donor memory CD8 T cells undergoing in vivo proliferation in lymphodepleted recipients also maintained their effector-associated demethylated status but acquired T EM -associated programs. These data demonstrate that effector-associated epigenetic programs are preserved during cytokine-driven subset interconversion of human memory CD8 T cells. © 2017 Abdelsamed et al.

  11. CD8+ T cells complement antibodies in protecting against yellow fever virus.

    Science.gov (United States)

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A; Fenger, Christina; Rasmussen, Michael; Skjødt, Karsten; Finsen, Bente; Stryhn, Anette; Buus, Søren; Christensen, Jan P; Thomsen, Allan R

    2015-02-01

    The attenuated yellow fever (YF) vaccine (YF-17D) was developed in the 1930s, yet little is known about the protective mechanisms underlying its efficiency. In this study, we analyzed the relative contribution of cell-mediated and humoral immunity to the vaccine-induced protection in a murine model of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune response inside the infected CNS, we observed an accelerated T cell influx into the brain after intracerebral challenge of vaccinated mice, and this T cell recruitment correlated with improved virus control in the brain. Using mice deficient in B cells we found that, in the absence of Abs, YF vaccination can still induce some antiviral protection, and in vivo depletion of CD8(+) T cells from these animals revealed a pivotal role for CD8(+) T cells in controlling virus replication in the absence of a humoral response. Finally, we demonstrated that effector CD8(+) T cells also contribute to viral control in the presence of circulating YF-specific Abs. To our knowledge, this is the first time that YF-specific CD8(+) T cells have been demonstrated to possess antiviral activity in vivo. Copyright © 2015 by The American Association of Immunologists, Inc.

  12. miR-150-Mediated Foxo1 Regulation Programs CD8+ T Cell Differentiation.

    Science.gov (United States)

    Ban, Young Ho; Oh, Se-Chan; Seo, Sang-Hwan; Kim, Seok-Min; Choi, In-Pyo; Greenberg, Philip D; Chang, Jun; Kim, Tae-Don; Ha, Sang-Jun

    2017-09-12

    MicroRNA (miR)-150 is a developmental regulator of several immune-cell types, but its role in CD8 + T cells is largely unexplored. Here, we show that miR-150 regulates the generation of memory CD8 + T cells. After acute virus infection, miR-150 knockout (KO) mice exhibited an accelerated differentiation of CD8 + T cells into memory cells and improved production of effector cytokines. Additionally, miR-150 KO CD8 + T cells displayed an enhanced recall response and improved protection against infections with another virus and bacteria. We found that forkhead box O1 (Foxo1) and T cell-specific transcription factor 1 (TCF1) are upregulated during the early activation phase in miR-150 KO CD8 + T cells and that miR-150 directly targets and suppresses Foxo1. These results suggest that miR-150-mediated suppression of Foxo1 regulates the balance between effector and memory cell differentiation, which might aid in the development of improved vaccines and T cell therapeutics. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Latent HIV reservoirs exhibit inherent resistance to elimination by CD8+ T cells.

    Science.gov (United States)

    Huang, Szu-Han; Ren, Yanqin; Thomas, Allison S; Chan, Dora; Mueller, Stefanie; Ward, Adam R; Patel, Shabnum; Bollard, Catherine M; Cruz, Conrad Russell; Karandish, Sara; Truong, Ronald; Macedo, Amanda B; Bosque, Alberto; Kovacs, Colin; Benko, Erika; Piechocka-Trocha, Alicja; Wong, Hing; Jeng, Emily; Nixon, Douglas F; Ho, Ya-Chi; Siliciano, Robert F; Walker, Bruce D; Jones, R Brad

    2018-02-01

    The presence of persistent, latent HIV reservoirs in CD4+ T cells obstructs current efforts to cure infection. The so-called kick-and-kill paradigm proposes to purge these reservoirs by combining latency-reversing agents with immune effectors such as cytotoxic T lymphocytes. Support for this approach is largely based on success in latency models, which do not fully reflect the makeup of latent reservoirs in individuals on long-term antiretroviral therapy (ART). Recent studies have shown that CD8+ T cells have the potential to recognize defective proviruses, which comprise the vast majority of all infected cells, and that the proviral landscape can be shaped over time due to in vivo clonal expansion of infected CD4+ T cells. Here, we have shown that treating CD4+ T cells from ART-treated individuals with combinations of potent latency-reversing agents and autologous CD8+ T cells consistently reduced cell-associated HIV DNA, but failed to deplete replication-competent virus. These CD8+ T cells recognized and potently eliminated CD4+ T cells that were newly infected with autologous reservoir virus, ruling out a role for both immune escape and CD8+ T cell dysfunction. Thus, our results suggest that cells harboring replication-competent HIV possess an inherent resistance to CD8+ T cells that may need to be addressed to cure infection.

  14. Memory CD8+ T Cells: Orchestrators and Key Players of Innate Immunity?

    Directory of Open Access Journals (Sweden)

    Grégoire Lauvau

    2016-09-01

    Full Text Available Over the past decades, the dichotomy between innate and adaptive immune responses has largely dominated our understanding of immunology. Upon primary encounter with microbial pathogens, differentiation of adaptive immune cells into functional effectors usually takes several days or even longer, making them contribute to host protection only late during primary infection. However, once generated, antigen-experienced T lymphocytes can persist in the organism and constitute a pool of memory cells that mediate fast and effective protection to a recall infection with the same microbial pathogen. Herein, we challenge this classical paradigm by highlighting the "innate nature" of memory CD8+ T cells. First, within the thymus or in the periphery, naïve CD8+ T cells may acquire phenotypic and functional characteristics of memory CD8+ T cells independently of challenge with foreign antigens. Second, both the "unconventional" and the "conventional" memory cells can rapidly express protective effector functions in response to sets of inflammatory cytokines and chemokines signals, independent of cognate antigen triggering. Third, memory CD8+ T cells can act by orchestrating the recruitment, activation, and licensing of innate cells, leading to broad antimicrobial states. Thus, collectively, memory CD8+ T cells may represent important actors of innate immune defenses.

  15. Age-related changes in CD8 T cell homeostasis and immunity to infection.

    Science.gov (United States)

    Nikolich-Žugich, Janko; Li, Gang; Uhrlaub, Jennifer L; Renkema, Kristin R; Smithey, Megan J

    2012-10-01

    Studies of CD8 T cell responses to vaccination or infection with various pathogens in both animal models and human subjects have revealed a markedly consistent array of age-related defects. In general, recent work shows that aged CD8 T cell responses are decreased in magnitude, and show poor differentiation into effector cells, with a reduced arsenal of effector functions. Here we review potential mechanisms underlying these defects. We specifically address phenotypic and numeric changes to the naïve CD8 T cell precursor pool, the impact of persistent viral infection(s) and inflammation, and contributions of the aging environment in which these cells are activated. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Cish actively silences TCR signaling in CD8+ T cells to maintain tumor tolerance.

    Science.gov (United States)

    Palmer, Douglas C; Guittard, Geoffrey C; Franco, Zulmarie; Crompton, Joseph G; Eil, Robert L; Patel, Shashank J; Ji, Yun; Van Panhuys, Nicholas; Klebanoff, Christopher A; Sukumar, Madhusudhanan; Clever, David; Chichura, Anna; Roychoudhuri, Rahul; Varma, Rajat; Wang, Ena; Gattinoni, Luca; Marincola, Francesco M; Balagopalan, Lakshmi; Samelson, Lawrence E; Restifo, Nicholas P

    2015-11-16

    Improving the functional avidity of effector T cells is critical in overcoming inhibitory factors within the tumor microenvironment and eliciting tumor regression. We have found that Cish, a member of the suppressor of cytokine signaling (SOCS) family, is induced by TCR stimulation in CD8(+) T cells and inhibits their functional avidity against tumors. Genetic deletion of Cish in CD8(+) T cells enhances their expansion, functional avidity, and cytokine polyfunctionality, resulting in pronounced and durable regression of established tumors. Although Cish is commonly thought to block STAT5 activation, we found that the primary molecular basis of Cish suppression is through inhibition of TCR signaling. Cish physically interacts with the TCR intermediate PLC-γ1, targeting it for proteasomal degradation after TCR stimulation. These findings establish a novel targetable interaction that regulates the functional avidity of tumor-specific CD8(+) T cells and can be manipulated to improve adoptive cancer immunotherapy.

  17. Bystander chronic infection negatively impacts development of CD8+ T cell memory

    Science.gov (United States)

    Stelekati, Erietta; Shin, Haina; Doering, Travis A.; Dolfi, Douglas V.; Ziegler, Carly G.; Beiting, Daniel P.; Dawson, Lucas; Liboon, Jennifer; Wolski, David; Ali, Mohammed-Alkhatim A.; Katsikis, Peter D.; Shen, Hao; Roos, David S.; Haining, W. Nicholas; Lauer, Georg M.; Wherry, E. John

    2014-01-01

    Summary Epidemiological evidence suggests that chronic infections impair immune responses to unrelated pathogens and vaccines. The underlying mechanisms, however, are unclear and distinguishing effects on priming versus development of immunological memory has been challenging. We investigated whether bystander chronic infections impact differentiation of memory CD8+ T cells, the hallmark of protective immunity against intracellular pathogens. Chronic bystander infections impaired development of memory CD8+ T cells in several mouse models and humans. These effects were independent of initial priming and were associated with chronic inflammatory signatures. Chronic inflammation negatively impacted the number of bystander CD8+ T cells and their memory development. Distinct underlying mechanisms of altered survival and differentiation were revealed with the latter regulated by the transcription factors T-bet and Blimp-1. Thus, exposure to prolonged bystander inflammation impairs the effector to memory transition. These data have relevance for immunity and vaccination during persisting infections and chronic inflammation. PMID:24837104

  18. Prolonged activation of virus-specific CD8+T cells after acute B19 infection

    DEFF Research Database (Denmark)

    Isa, Adiba; Kasprowicz, Victoria; Norbeck, Oscar

    2005-01-01

    BACKGROUND: Human parvovirus B19 (B19) is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS......: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia......, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function...

  19. Neutrophil trails guide influenza-specific CD8⁺ T cells in the airways.

    Science.gov (United States)

    Lim, Kihong; Hyun, Young-Min; Lambert-Emo, Kris; Capece, Tara; Bae, Seyeon; Miller, Richard; Topham, David J; Kim, Minsoo

    2015-09-04

    During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells are unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8(+) T cell-mediated immune protection in mice. We observed that migrating neutrophils leave behind long-lasting trails that are enriched in the chemokine CXCL12. Experiments with granulocyte-specific CXCL12 conditionally depleted mice and a CXCR4 antagonist revealed that CXCL12 derived from neutrophil trails is critical for virus-specific CD8(+) T cell recruitment and effector functions. Collectively, these results suggest that neutrophils deposit long-lasting, chemokine-containing trails, which may provide both chemotactic and haptotactic cues for efficient CD8(+) T cell migration and localization in influenza-infected tissues. Copyright © 2015, American Association for the Advancement of Science.

  20. Neutrophil trails guide influenza-specific CD8+ T cells in the airways

    Science.gov (United States)

    Lim, Kihong; Hyun, Young-Min; Lambert-Emo, Kris; Capece, Tara; Bae, Seyeon; Miller, Richard; Topham, David J.; Kim, Minsoo

    2016-01-01

    During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells is unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8+ T cell-mediated immune protection in mice. We observed that migrating neutrophils leave behind long-lasting trails that are enriched in the chemokine CXCL12. Experiments with granulocyte-specific CXCL12 conditional knock-out mice and a CXCR4 antagonist revealed that CXCL12 derived from neutrophil trails is critical for virus-specific CD8+ T cell recruitment and effector functions. Collectively, these results suggest neutrophils deposit long-lasting, chemokine-containing trails, which may provide both chemotactic and haptotactic cues for efficient CD8+ T cell migration and localization in influenza-infected tissues. PMID:26339033

  1. Phenotypic alteration of CD8+ T cells in chronic lymphocytic leukemia is associated with epigenetic reprogramming.

    Science.gov (United States)

    Wu, Jiazhu; Xu, Xiaojing; Lee, Eun-Joon; Shull, Austin Y; Pei, Lirong; Awan, Farrukh; Wang, Xiaoling; Choi, Jeong-Hyeon; Deng, Libin; Xin, Hong-Bo; Zhong, Wenxun; Liang, Jinhua; Miao, Yi; Wu, Yujie; Fan, Lei; Li, Jianyong; Xu, Wei; Shi, Huidong

    2016-06-28

    Immunosuppression is a prevalent clinical feature in chronic lymphocytic leukemia (CLL) patients, with many patients demonstrating increased susceptibility to infections as well as increased failure of an antitumor immune response. However, much is currently not understood regarding the precise mechanisms that attribute to this immunosuppressive phenotype in CLL. To provide further clarity to this particular phenomenon, we analyzed the T-cell profile of CLL patient samples within a large cohort and observed that patients with an inverted CD4/CD8 ratio had a shorter time to first treatment as well as overall survival. These observations coincided with higher expression of the immune checkpoint receptor PD-1 in CLL patient CD8+ T cells when compared to age-matched healthy donors. Interestingly, we discovered that increased PD-1 expression in CD8+ T cells corresponds with decreased DNA methylation levels in a distal upstream locus of the PD-1 gene PDCD1. Further analysis using luciferase reporter assays suggests that the identified PDCD1 distal upstream region acts as an enhancer for PDCD1 transcription and this region becomes demethylated during activation of naïve CD8+ T cells by anti-CD3/anti-CD28 antibodies and IL2. Finally, we conducted a genome-wide DNA methylation analysis comparing CD8+ T cells from CLL patients against healthy donors and identified additional differentially methylated genes with known immune regulatory functions including CCR6 and KLRG1. Taken together, our findings reveal the occurrence of epigenetic reprogramming taking place within CLL patient CD8+ T cells and highlight the potential mechanism of how immunosuppression is accomplished in CLL.

  2. Skin vaccination with live virus vectored microneedle arrays induce long lived CD8(+) T cell memory.

    Science.gov (United States)

    Becker, Pablo D; Hervouet, Catherine; Mason, Gavin M; Kwon, Sung-Yun; Klavinskis, Linda S

    2015-09-08

    A simple dissolvable microneedle array (MA) platform has emerged as a promising technology for vaccine delivery, due to needle-free injection with a formulation that preserves the immunogenicity of live viral vectored vaccines dried in the MA matrix. While recent studies have focused largely on design parameters optimized to induce primary CD8(+) T cell responses, the hallmark of a vaccine is synonymous with engendering long-lasting memory. Here, we address the capacity of dried MA vaccination to programme phenotypic markers indicative of effector/memory CD8(+) T cell subsets and also responsiveness to recall antigen benchmarked against conventional intradermal (ID) injection. We show that despite a slightly lower frequency of dividing T cell receptor transgenic CD8(+) T cells in secondary lymphoid tissue at an early time point, the absolute number of CD8(+) T cells expressing an effector memory (CD62L(-)CD127(+)) and central memory (CD62L(+)CD127(+)) phenotype during peak expansion were comparable after MA and ID vaccination with a recombinant human adenovirus type 5 vector (AdHu5) encoding HIV-1 gag. Similarly, both vaccination routes generated CD8(+) memory T cell subsets detected in draining LNs for at least two years post-vaccination capable of responding to secondary antigen. These data suggest that CD8(+) T cell effector/memory generation and long-term memory is largely unaffected by physical differences in vaccine delivery to the skin via dried MA or ID suspension. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

    Directory of Open Access Journals (Sweden)

    Adiba Isa

    2005-12-01

    Full Text Available Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously.The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low.This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

  4. Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available BACKGROUND: Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low. CONCLUSION: This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

  5. Tumor-infiltrating CD8+ lymphocytes effect on clinical outcome of muco-cutaneous melanoma

    Directory of Open Access Journals (Sweden)

    Mahtab Rahbar

    2015-01-01

    Full Text Available Background: Recent data have changed our views of prognostic factors in cutaneous melanoma, while some newer methods have yielded better prognostic information. Tumor-infiltrating lymphocytes are believed to represent the immune reaction/response to melanoma cells which is often found in melanocytic cancer. Aim and Objective: We carried out an analysis, aiming to establish pooled estimates for clinical outcomes based on the presence of CD8+ T cell in melanocytic cancer. Materials and Methods: We have included 42 patients with primary cutaneous melanocytic cancer without preoperative treatments in our study. We next analyzed the proliferative activity of CD8+ T cells that infiltrated in tumor cell nests. The intratumoral and adjacent to invasive margin of tumor CD+ T-cell infiltration were analyzed which could also reflect antitumor immunity. Results: The total number of CD8+ cells especially adjacent to invasive margin of tumor was positively correlated with anatomical tumor thickness (P < .001 and not correlated with patient′s age and sex. The stage of tumor which is related to vascular-neural invasion, regional lymph nodes involvement and tumor thickness shows positive correlation with CD8+ infiltration in tumor (P < .004, P < .005, P < .001, respectively. Acral melanoma shows more CD8 lymphocytes infiltration and also recurrence rate of tumor (P < .005. Conclusion: We believe that CD8+ T-cell infiltration in primary cutaneous melanocytic cancer represents the immune reaction/response to melanoma which could be an important new therapy for melanoma although more research is needed on this treatment modality.

  6. CD40L Expression Allows CD8+ T Cells to Promote Their Own Expansion and Differentiation through Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Neil Q. Tay

    2017-11-01

    Full Text Available CD8+ T cells play an important role in providing protective immunity against a wide range of pathogens, and a number of different factors control their activation. Although CD40L-mediated CD40 licensing of dendritic cells (DCs by CD4+ T cells is known to be necessary for the generation of a robust CD8+ T cell response, the contribution of CD8+ T cell-expressed CD40L on DC licensing is less clear. We have previously shown that CD8+ T cells are able to induce the production of IL-12 p70 by DCs in a CD40L-dependent manner, providing some evidence that CD8+ T cell-mediated activation of DCs is possible. To better understand the role of CD40L on CD8+ T cell responses, we generated and characterized CD40L-expressing CD8+ T cells both in vitro and in vivo. We found that CD40L was expressed on 30–50% of effector CD8+ T cells when stimulated and that this expression was transient. The expression of CD40L on CD8+ T cells promoted the proliferation and differentiation of both the CD40L-expressing CD8+ T cells and the bystander effector CD8+ T cells. This process occurred via a cell-extrinsic manner and was mediated by DCs. These data demonstrate the existence of a mechanism where CD8+ T cells and DCs cooperate to maximize CD8+ T cell responses.

  7. Epigenetic landscapes reveal transcription factors that regulate CD8+ T cell differentiation.

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P; Pereira, Renata M; Crotty, Shane; Chang, John T; Pipkin, Matthew E; Wang, Wei; Goldrath, Ananda W

    2017-05-01

    Dynamic changes in the expression of transcription factors (TFs) can influence the specification of distinct CD8 + T cell fates, but the observation of equivalent expression of TFs among differentially fated precursor cells suggests additional underlying mechanisms. Here we profiled the genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8 + T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that the expression and binding of TFs contributed to the establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal key TFs that influence the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8 + T cell differentiation, regulated the formation of terminal-effector cell fates and memory-precursor cell fates, respectively. Our data define the epigenetic landscape of differentiation intermediates and facilitate the identification of TFs with previously unappreciated roles in CD8 + T cell differentiation.

  8. Epigenetic landscapes reveal transcription factors regulating CD8+ T cell differentiation

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J. Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P.; Pereira, Renata M.; Crotty, Shane; Chang, John T.; Pipkin, Matthew E.; Wang, Wei; Goldrath, Ananda W.

    2017-01-01

    Dynamic changes in the expression of transcription factors (TFs) can influence specification of distinct CD8+ T cell fates, but the observation of equivalent expression of TF among differentially-fated precursor cells suggests additional underlying mechanisms. Here, we profiled genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8+ T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that TF expression and binding contributed to establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal novel TFs influencing the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8+ T cell differentiation, regulated the formation of terminal-effector and memory-precursor cell-fates, respectively. Our data define the epigenetic landscape of differentiation intermediates, facilitating identification of TFs with previously unappreciated roles in CD8+ T cell differentiation. PMID:28288100

  9. CD103 is a marker for alloantigen-induced regulatory CD8+ T cells

    NARCIS (Netherlands)

    Uss, Elena; Rowshani, Ajda T.; Hooibrink, Berend; Lardy, Neubury M.; van Lier, René A. W.; ten Berge, Ineke J. M.

    2006-01-01

    The alphaEbeta7 integrin CD103 may direct lymphocytes to its ligand E-cadherin. CD103 is expressed on T cells in lung and gut and on allograft-infiltrating T cells. Moreover, recent studies have documented expression of CD103 on CD4+ regulatory T cells. Approximately 4% of circulating CD8+ T cells

  10. AMPKα1: a glucose sensor that controls CD8 T-cell memory.

    Science.gov (United States)

    Rolf, Julia; Zarrouk, Marouan; Finlay, David K; Foretz, Marc; Viollet, Benoit; Cantrell, Doreen A

    2013-04-01

    The adenosine monophosphate-activated protein kinase (AMPK) is activated by antigen receptor signals and energy stress in T cells. In many cell types, AMPK can maintain energy homeostasis and can enforce quiescence to limit energy demands. We consequently evaluated the importance of AMPK for controlling the transition of metabolically active effector CD8 T lymphocytes to the metabolically quiescent catabolic memory T cells during the contraction phase of the immune response. We show that AMPKα1 activates rapidly in response to the metabolic stress caused by glucose deprivation of CD8 cytotoxic T lymphocytes (CTLs). Moreover, AMPKα1 restrains mammalian target of rapamycin complex 1 activity under conditions of glucose stress. AMPKα1 activity is dispensable for proliferation and differentiation of CTLs. However, AMPKα1 is required for in vivo survival of CTLs following withdrawal of immune stimulation. AMPKα1(null) T cells also show a striking defect in their ability to generate memory CD8 T-cell responses during Listeria monocytogenes infection. These results show that AMPKα1 monitors energy stress in CTLs and controls CD8 T-cell memory. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Herpes simplex virus-1 evasion of CD8+ T cell accumulation contributes to viral encephalitis.

    Science.gov (United States)

    Koyanagi, Naoto; Imai, Takahiko; Shindo, Keiko; Sato, Ayuko; Fujii, Wataru; Ichinohe, Takeshi; Takemura, Naoki; Kakuta, Shigeru; Uematsu, Satoshi; Kiyono, Hiroshi; Maruzuru, Yuhei; Arii, Jun; Kato, Akihisa; Kawaguchi, Yasushi

    2017-10-02

    Herpes simplex virus-1 (HSV-1) is the most common cause of sporadic viral encephalitis, which can be lethal or result in severe neurological defects even with antiviral therapy. While HSV-1 causes encephalitis in spite of HSV-1-specific humoral and cellular immunity, the mechanism by which HSV-1 evades the immune system in the central nervous system (CNS) remains unknown. Here we describe a strategy by which HSV-1 avoids immune targeting in the CNS. The HSV-1 UL13 kinase promotes evasion of HSV-1-specific CD8+ T cell accumulation in infection sites by downregulating expression of the CD8+ T cell attractant chemokine CXCL9 in the CNS of infected mice, leading to increased HSV-1 mortality due to encephalitis. Direct injection of CXCL9 into the CNS infection site enhanced HSV-1-specific CD8+ T cell accumulation, leading to marked improvements in the survival of infected mice. This previously uncharacterized strategy for HSV-1 evasion of CD8+ T cell accumulation in the CNS has important implications for understanding the pathogenesis and clinical treatment of HSV-1 encephalitis.

  12. Influence of race on microsatellite instability and CD8+ T cell infiltration in colon cancer.

    Directory of Open Access Journals (Sweden)

    John M Carethers

    Full Text Available African American patients with colorectal cancer show higher mortality than their Caucasian counterparts. Biology might play a partial role, and prior studies suggest a higher prevalence for microsatellite instability (MSI among cancers from African Americans, albeit patients with MSI cancers have improved survival over patients with non-MSI cancers, counter to the outcome observed for African American patients. CD8+ T cell infiltration of colon cancer is postively correlated with MSI tumors, and is also related to improved outcome. Here, we utilized a 503-person, population-based colon cancer cohort comprising 45% African Americans to determine, under blinded conditions from all epidemiological data, the prevalence of MSI and associated CD8+ T cell infiltration within the cancers. Among Caucasian cancers, 14% were MSI, whereas African American cancers demonstrated 7% MSI (P = 0.009. Clinically, MSI cancers between races were similar; among microsatellite stable cancers, African American patients were younger, female, and with proximal cancers. CD8+ T cells were higher in MSI cancers (88.0 vs 30.4/hpf, P<0.0001, but was not different between races. Utilizing this population-based cohort, African American cancers show half the MSI prevalence of Caucasians without change in CD8+ T cell infiltration which may contribute towards their higher mortality from colon cancer.

  13. Role of CD5-negative CD8 T Cells in Adaptation to Antigenic ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of 3-oxotirucalla-7, 24-dien-21-oic acid on CD8+ T cell recovery in human immunodeficiency ..... enhances the probability of immune system recovery. ... PE: Fine tuning of TCR signaling by CD5. J Immunol.

  14. CD4 cells can be more efficient at tumor rejection than CD8 cells.

    Science.gov (United States)

    Perez-Diez, Ainhoa; Joncker, Nathalie T; Choi, Kyungho; Chan, William F N; Anderson, Colin C; Lantz, Olivier; Matzinger, Polly

    2007-06-15

    Researchers designing antitumor treatments have long focused on eliciting tumor-specific CD8 cytotoxic T lymphocytes (CTL) because of their potent killing activity and their ability to reject transplanted organs. The resulting treatments, however, have generally been surprisingly poor at inducing complete tumor rejection, both in experimental models and in the clinic. Although a few scattered studies suggested that CD4 T "helper" cells might also serve as antitumor effectors, they have generally been studied mostly for their ability to enhance the activity of CTL. In this mouse study, we compared monoclonal populations of tumor-specific CD4 and CD8 T cells as effectors against several different tumors, and found that CD4 T cells eliminated tumors that were resistant to CD8-mediated rejection, even in cases where the tumors expressed major histocompatibility complex (MHC) class I molecules but not MHC class II. MHC class II expression on host tissues was critical, suggesting that the CD4 T cells act indirectly. Indeed, the CD4 T cells partnered with NK cells to obtain the maximal antitumor effect. These findings suggest that CD4 T cells can be powerful antitumor effector cells that can, in some cases, outperform CD8 T cells, which are the current "gold standard" effector cell in tumor immunotherapy.

  15. Cognate antigen stimulation generates potent CD8+ inflammatory effector T cells.

    Directory of Open Access Journals (Sweden)

    Hsueh-Cheng eSung

    2013-12-01

    Full Text Available Inflammatory reactions are believed to be triggered by innate signals and have a major protective role by recruiting innate immunity cells, favoring lymphocyte activation and differentiation, and thus contributing to the sequestration and elimination of the injurious stimuli. Although certain lymphocyte types such as TH17 cells co-participate in inflammatory reactions, their generation from the naïve pool requires the pre-existence of an inflammatory milieu. In this context, inflammation is always regarded as beginning with an innate response that may be eventually perpetuated and amplified by certain lymphocyte types. In contrast, we here show that even in sterile immunizations or in MyD88 deficient mice, CD8 T cells produce a burst of pro-inflammatory cytokines and chemokines. These functions follow opposite rules to the classic CD8 effector functions since they are generated prior to cell expansion and decline before antigen elimination. As few as 56 CD8+ inflammatory effector cells in a lymph node can mobilize 107 cells in 24h, including lymphocytes, natural killer cells and several accessory cell types involved in inflammatory reactions. Thus, although inflammation modulates cognate responses, CD8 cognate responses also initiate local inflammatory reactions.

  16. Evaluation of CD4+/CD8+ status and urinary tract infections ...

    African Journals Online (AJOL)

    The CD4+ and the CD8+ counts were correlated with the ova of S. haematobium in their urine samples at r = 0.0108 and r = 0.516 respectively. The bacteriuria, urinary schistosomiasis and urinary tract co - infections namely; Escherichia coli, Proteus, Pseudomonas aeroginosa, Staphylococcus epidermidis and Staph.

  17. Phenotyping of circulating CD8(+) T cell subsets in human cutaneous leishmaniasis

    Czech Academy of Sciences Publication Activity Database

    Khamesipour, A.; Rostami, M.N.; Tasbihi, M.; Mohammadi, A.M.; Shahrestani, T.; Sarrafnejad, A.; Sohrabi, Yahya; Eskandari, S.E.; Valian, H.K.

    2012-01-01

    Roč. 14, č. 9 (2012), s. 702-711 ISSN 1286-4579 Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:68378050 Keywords : CD8(+) T cells * memory T cells * cutaneous leishmania sis * IFN-gamma Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.920, year: 2012

  18. Activated CD8+T cells contribute to clearance of gastric Cryptosporidium muris infections

    Czech Academy of Sciences Publication Activity Database

    Kváč, Martin; Kodádková, Alena; Sak, Bohumil; Květoňová, Dana; Jalovecká, M.; Rost, M.; Salát, Jiří

    2011-01-01

    Roč. 33, č. 4 (2011), 210-216 ISSN 0141-9838 R&D Projects: GA AV ČR KJB500960701 Institutional research plan: CEZ:AV0Z60220518 Keywords : CD4+T-lymphocytes * CD8+T-lymphocytes * Cryptosporidium muris * T-cell-mediated immunity Subject RIV: EC - Immunology Impact factor: 2.601, year: 2011

  19. IL-6 trans-Signaling-Dependent Rapid Development of Cytotoxic CD8+ T Cell Function

    Directory of Open Access Journals (Sweden)

    Jan P. Böttcher

    2014-09-01

    Full Text Available Immune control of infections with viruses or intracellular bacteria relies on cytotoxic CD8+ T cells that use granzyme B (GzmB for elimination of infected cells. During inflammation, mature antigen-presenting dendritic cells instruct naive T cells within lymphoid organs to develop into effector T cells. Here, we report a mechanistically distinct and more rapid process of effector T cell development occurring within 18 hr. Such rapid acquisition of effector T cell function occurred through cross-presenting liver sinusoidal endothelial cells (LSECs in the absence of innate immune stimulation and known costimulatory signaling. Rather, interleukin-6 (IL-6 trans-signaling was required and sufficient for rapid induction of GzmB expression in CD8+ T cells. Such LSEC-stimulated GzmB-expressing CD8+ T cells further responded to inflammatory cytokines, eliciting increased and protracted effector functions. Our findings identify a role for IL-6 trans-signaling in rapid generation of effector function in CD8+ T cells that may be beneficial for vaccination strategies.

  20. Profiling the Targets of Protective CD8+ T Cell Responses to Infection

    Directory of Open Access Journals (Sweden)

    Joseph T. Bruder

    2017-12-01

    Full Text Available T cells are critical effectors of host immunity that target intracellular pathogens, such as the causative agents of HIV, tuberculosis, and malaria. The development of vaccines that induce effective cell-mediated immunity against such pathogens has proved challenging; for tuberculosis and malaria, many of the antigens targeted by protective T cells are not known. Here, we report a novel approach for screening large numbers of antigens as potential targets of T cells. Malaria provides an excellent model to test this antigen discovery platform because T cells are critical mediators of protection following immunization with live sporozoite vaccines and the specific antigen targets are unknown. We generated an adenovirus array by cloning 312 highly expressed pre-erythrocytic Plasmodium yoelii antigens into adenovirus vectors using high-throughput methodologies. The array was screened to identify antigen-specific CD8+ T cells induced by a live sporozoite vaccine regimen known to provide high levels of sterile protection mediated by CD8+ T cells. We identified 69 antigens that were targeted by CD8+ T cells induced by this vaccine regimen. The antigen that recalled the highest frequency of CD8+ T cells, PY02605, induced protective responses in mice, demonstrating proof of principle for this approach in identifying antigens for vaccine development.

  1. The new numerology of immunity mediated by virus-specific CD8(+) T cells.

    Science.gov (United States)

    Doherty, P C

    1998-08-01

    Our understanding of virus-specific CD8(+) T cell responses is currently being revolutionized by peptide-based assay systems that allow flow cytometric analysis of effector and memory cytotoxic T lymphocyte populations. These techniques are, for the first time, putting the analysis of T-cell-mediated immunity on a quantitative basis.

  2. Role of CD5-negative CD8 + T Cells in Adaptation to Antigenic ...

    African Journals Online (AJOL)

    + T cell recovery in human immunodeficiency virus type 1 (HIV-1) disease. Methods: The increase in the rates of CD8+ T cells over 48 weeks following treatment with 3- oxotirucalla-7, 24-dien-21-oic acid was investigated. Plasma HIV-1 load ...

  3. Public TCR Use by Herpes Simplex Virus-2-Specific Human CD8 CTLs

    NARCIS (Netherlands)

    Dong, Lichun; Li, Penny; Oenema, Tjitske; McClurkan, Christopher L.; Koelle, David M.

    2010-01-01

    Recombination of germline TCR alpha and beta genes generates polypeptide receptors for MHC peptide. Ag exposure during long-term herpes simplex infections may shape the T cell repertoire over time. We investigated the CD8 T cell response to HSV-2 in chronically infected individuals by sequencing the

  4. Increased memory phenotypes of CD4+ and CD8+ T cells in ...

    African Journals Online (AJOL)

    Conclusions: Children with SCA in Tanzania show an absolute increase in all leukocyte types, including lymphocytes, with skewing of both CD4+ and CD8+ T cells towards the memory phenotypes. These findings provide insights on the development of adaptive immunity which may have implications on vaccine ...

  5. Cross-reactive microbial peptides can modulate HIV-specific CD8+ T cell responses.

    Directory of Open Access Journals (Sweden)

    Christopher W Pohlmeyer

    Full Text Available Heterologous immunity is an important aspect of the adaptive immune response. We hypothesized that this process could modulate the HIV-1-specific CD8+ T cell response, which has been shown to play an important role in HIV-1 immunity and control. We found that stimulation of peripheral blood mononuclear cells (PBMCs from HIV-1-positive subjects with microbial peptides that were cross-reactive with immunodominant HIV-1 epitopes resulted in dramatic expansion of HIV-1-specific CD8+ T cells. Interestingly, the TCR repertoire of HIV-1-specific CD8+ T cells generated by ex vivo stimulation of PBMCs using HIV-1 peptide was different from that of cells stimulated with cross-reactive microbial peptides in some HIV-1-positive subjects. Despite these differences, CD8+ T cells stimulated with either HIV-1 or cross-reactive peptides effectively suppressed HIV-1 replication in autologous CD4+ T cells. These data suggest that exposure to cross-reactive microbial antigens can modulate HIV-1-specific immunity.

  6. Weak anti-HIV CD8+ T-cell effector activity in HIV primary infection

    Science.gov (United States)

    Dalod, Marc; Dupuis, Marion; Deschemin, Jean-Christophe; Goujard, Cécile; Deveau, Christiane; Meyer, Laurence; Ngo, Nicole; Rouzioux, Christine; Guillet, Jean-Gérard; Delfraissy, Jean-François; Sinet, Martine; Venet, Alain

    1999-01-01

    HIV-specific CD8+ T cells play a major role in the control of virus during HIV primary infection (PI) but do not completely prevent viral replication. We used IFN-γ enzyme-linked immunospot assay and intracellular staining to characterize the ex vivo CD8+ T-cell responses to a large variety of HIV epitopic peptides in 24 subjects with early HIV PI. We observed HIV-specific responses in 71% of subjects. Gag and Nef peptides were more frequently recognized than Env and Pol peptides. The number of peptides recognized was low (median 2, range 0–6). In contrast, a much broader response was observed in 30 asymptomatic subjects with chronic infection: all were responders with a median of 5 peptides recognized (range 1–13). The frequency of HIV-specific CD8+ T cells among PBMC for a given peptide was of the same order of magnitude in both groups. The proportion of HIV-specific CD8+CD28– terminally differentiated T cells was much lower in PI than at the chronic stage of infection. The weakness of the immune response during HIV PI could partially account for the failure to control HIV. These findings have potential importance for defining immunotherapeutic strategies and establishing the goals for effective vaccination. J. Clin. Invest. 104:1431–1439 (1999). PMID:10562305

  7. CD8+ T Cell-Mediated Immunity during Trypanosoma cruzi Infection: A Path for Vaccine Development?

    Directory of Open Access Journals (Sweden)

    Fernando dos Santos Virgilio

    2014-01-01

    Full Text Available MHC-restricted CD8+ T cells are important during infection with the intracellular protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Experimental studies performed in the past 25 years have elucidated a number of features related to the immune response mediated by these T cells, which are important for establishing the parasite/host equilibrium leading to chronic infection. CD8+ T cells are specific for highly immunodominant antigens expressed by members of the trans-sialidase family. After infection, their activation is delayed, and the cells display a high proliferative activity associated with high apoptotic rates. Although they participate in parasite control and elimination, they are unable to clear the infection due to their low fitness, allowing the parasite to establish the chronic phase when these cells then play an active role in the induction of heart immunopathology. Vaccination with a number of subunit recombinant vaccines aimed at eliciting specific CD8+ T cells can reverse this path, thereby generating a productive immune response that will lead to the control of infection, reduction of symptoms, and reduction of disease transmission. Due to these attributes, activation of CD8+ T lymphocytes may constitute a path for the development of a veterinarian or human vaccine.

  8. Proliferation requirements of cytomegalovirus-specific, effector-type human CD8+ T cells

    NARCIS (Netherlands)

    van Leeuwen, Ester M.; Gamadia, Laila E.; Baars, Paul A.; Remmerswaal, Ester B.; ten Berge, Ineke J.; van Lier, René A.

    2002-01-01

    Two prototypic types of virus-specific CD8(+) T cells can be found in latently infected individuals: CD45R0(+)CD27(+)CCR7(-) effector-memory, and CD45RA(+)CD27(-)CCR7(-) effector-type cells. It has recently been implied that CD45RA(+)CD27(-)CCR7(-) T cells are terminally differentiated effector

  9. CD8 T cell memory to a viral pathogen requires trans cosignaling between HVEM and BTLA.

    Directory of Open Access Journals (Sweden)

    Rachel Flynn

    Full Text Available Defining the molecular interactions required to program activated CD8 T cells to survive and become memory cells may allow us to understand how to augment anti-viral immunity. HVEM (herpes virus entry mediator is a member of the tumor necrosis factor receptor (TNFR family that interacts with ligands in the TNF family, LIGHT and Lymphotoxin-α, and in the Ig family, B and T lymphocyte attenuator (BTLA and CD160. The Ig family members initiate inhibitory signaling when engaged with HVEM, but may also activate survival gene expression. Using a model of vaccinia virus infection, we made the unexpected finding that deficiency in HVEM or BTLA profoundly impaired effector CD8 T cell survival and development of protective immune memory. Mixed adoptive transfer experiments indicated that BTLA expressed in CD8α+ dendritic cells functions as a trans-activating ligand that delivers positive co-signals through HVEM expressed in T cells. Our data demonstrate a critical role of HVEM-BTLA bidirectional cosignaling system in antiviral defenses by driving the differentiation of memory CD8 T cells.

  10. MicroRNA Expression Patterns of CD8+ T Cells in Acute and Chronic Brucellosis

    Science.gov (United States)

    Budak, Ferah; Bal, S. Haldun; Tezcan, Gulcin; Guvenc, Furkan; Akalin, E. Halis; Goral, Guher; Deniz, Gunnur

    2016-01-01

    Although our knowledge about Brucella virulence factors and the host response increase rapidly, the mechanisms of immune evasion by the pathogen and causes of chronic disease are still unknown. Here, we aimed to investigate the immunological factors which belong to CD8+ T cells and their roles in the transition of brucellosis from acute to chronic infection. Using miRNA microarray, more than 2000 miRNAs were screened in CD8+ T cells of patients with acute or chronic brucellosis and healthy controls that were sorted from peripheral blood with flow cytometry and validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Expression of two miRNAs were determined to display a significant fold change in chronic group when compared with acute or control groups. Both miRNAs (miR-126-5p and miR-4753-3p) were decreased (p 2). These miRNAs have the potential to be the regulators of CD8+ T cell-related marker genes for chronic brucellosis infections. The differentially expressed miRNAs and their predicted target genes are involved in MAPK signaling pathway, cytokine-cytokine receptor interactions, endocytosis, regulation of actin cytoskeleton, and focal adhesion indicating their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human CD8+ T cells to clarify the mechanism of inveteracy in brucellosis. PMID:27824867

  11. Flow Cytometric Analysis of Leishmania Reactive CD4+/CD8+ Lymphocyte Proliferation in Cutaneous Leishmaniasis

    Directory of Open Access Journals (Sweden)

    H Keshavarz

    2008-12-01

    Full Text Available Background: Determination of the division history of T cells in vitro is helpful in the study of effector mechanisms against infections. Technique described here uses the intracellular fluorescent label carboxyfluorescein diacetate succinimidyl ester (CFSE to monitor the proliferation. Methods: In a cross sectional study, blood samples were collected from 7 volunteers with history of cutaneous leishmania­sis (CL and one healthy control from endemic areas in Isfahan province who referred to the Center for Research and Training in Skin Diseases and Leprosy (CRTSDL, then CD4+/CD8+ lymphocytes and CD14+ monocytes were isolated from peri­pheral blood mononuclear cells (PBMC using mAbs and magnetic nanoparticles. CFSE labeled CD4+ or CD8+ lympho­cytes cultured with autologous monocytes in the presence of PHA, SLA, live Leishmania major or as control with­out sti­mulation. Cells were harvested after 7 days and were analyzed using flow cytometry. Results: Five consecutive divisions were monitored separately. Stimulation of CD4+ or CD8+ lymphocytes from CL sub­jects with SLA showed a significant difference in proliferation comparing with unstimulated cells (P< 0.05. The signifi­cant difference in the percentages of CD4+ cells stimulated with SLA was revealed at different divisions for each subject. In CD8+ lymphocyte, significant stronger stimulation of SLA was evident later in the proliferation process. The mean number of divisions in both CD4+/CD8+ lymphocytes stimulated with SLA was significantly greater than when stimulated with live L. major (P=0.007 / P=0.012, respectively Conclusion: The percentage of divided cells might be calculated separately in each division. The cells remained active following CFSE staining and there is possibility of functional analysis simultaneously.

  12. Cytotoxic potential of decidual NK cells and CD8+ T cells awakened by infections.

    Science.gov (United States)

    Crespo, Ângela C; van der Zwan, Anita; Ramalho-Santos, João; Strominger, Jack L; Tilburgs, Tamara

    2017-02-01

    To establish a healthy pregnancy the maternal immune system must tolerate fetal allo-antigens, yet remain competent to respond to infections. The ability of decidual NK cells (dNK) to promote migration of fetal extravillous trophoblasts (EVT) and placental growth as well as the capacity of EVT to promote immune tolerance are topics of high interest and extensive research. However, the problem of how dNK and decidual CD8+ T cells (CD8+ dT) provide immunity to infections of the placenta and the mechanisms that regulate their cytolytic function has thus far largely been ignored. Fetal EVT are the most invasive cells of the placenta and directly interact with maternal decidual immune cells at this maternal-fetal interface. Besides the expression of non-polymorphic HLA-E and HLA-G molecules that are associated with immune tolerance, EVT also express highly polymorphic HLA-C molecules that can serve as targets for maternal dNK and CD8+ dT responses. HLA-C expression by EVT has a dual role as the main molecule to which immune tolerance needs to be established and as the only molecule that can present pathogen-derived peptides and provide protective immunity when EVT are infected. The focus of this review is to address the regulation of cytotoxicity of dNK and CD8+ dT, which is essential for maternal-fetal immune tolerance as well as recent evidence that both cell types can provide immunity to infections at the maternal-fetal interface. A particular emphasis is given to the role of HLA-C expressed by EVT and its capacity to elicit dNK and CD8+ dT responses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Natural killer cells promote early CD8 T cell responses against cytomegalovirus.

    Directory of Open Access Journals (Sweden)

    Scott H Robbins

    2007-08-01

    Full Text Available Understanding the mechanisms that help promote protective immune responses to pathogens is a major challenge in biomedical research and an important goal for the design of innovative therapeutic or vaccination strategies. While natural killer (NK cells can directly contribute to the control of viral replication, whether, and how, they may help orchestrate global antiviral defense is largely unknown. To address this question, we took advantage of the well-defined molecular interactions involved in the recognition of mouse cytomegalovirus (MCMV by NK cells. By using congenic or mutant mice and wild-type versus genetically engineered viruses, we examined the consequences on antiviral CD8 T cell responses of specific defects in the ability of the NK cells to control MCMV. This system allowed us to demonstrate, to our knowledge for the first time, that NK cells accelerate CD8 T cell responses against a viral infection in vivo. Moreover, we identify the underlying mechanism as the ability of NK cells to limit IFN-alpha/beta production to levels not immunosuppressive to the host. This is achieved through the early control of cytomegalovirus, which dramatically reduces the activation of plasmacytoid dendritic cells (pDCs for cytokine production, preserves the conventional dendritic cell (cDC compartment, and accelerates antiviral CD8 T cell responses. Conversely, exogenous IFN-alpha administration in resistant animals ablates cDCs and delays CD8 T cell activation in the face of NK cell control of viral replication. Collectively, our data demonstrate that the ability of NK cells to respond very early to cytomegalovirus infection critically contributes to balance the intensity of other innate immune responses, which dampens early immunopathology and promotes optimal initiation of antiviral CD8 T cell responses. Thus, the extent to which NK cell responses benefit the host goes beyond their direct antiviral effects and extends to the prevention of innate

  14. Interferon-alpha administration enhances CD8+ T cell activation in HIV infection.

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    Maura Manion

    Full Text Available Type I interferons play important roles in innate immune defense. In HIV infection, type I interferons may delay disease progression by inhibiting viral replication while at the same time accelerating disease progression by contributing to chronic immune activation.To investigate the effects of type I interferons in HIV-infection, we obtained cryopreserved peripheral blood mononuclear cell samples from 10 subjects who participated in AIDS Clinical Trials Group Study 5192, a trial investigating the activity of systemic administration of IFNα for twelve weeks to patients with untreated HIV infection. Using flow cytometry, we examined changes in cell cycle status and expression of activation antigens by circulating T cells and their maturation subsets before, during and after IFNα treatment.The proportion of CD38+HLA-DR+CD8+ T cells increased from a mean of 11.7% at baseline to 24.1% after twelve weeks of interferon treatment (p = 0.006. These frequencies dropped to an average of 20.1% six weeks after the end of treatment. In contrast to CD8+ T cells, the frequencies of activated CD4+ T cells did not change with administration of type I interferon (mean percentage of CD38+DR+ cells = 2.62% at baseline and 2.17% after 12 weeks of interferon therapy. As plasma HIV levels fell with interferon therapy, this was correlated with a "paradoxical" increase in CD8+ T cell activation (p<0.001.Administration of type I interferon increased expression of the activation markers CD38 and HLA DR on CD8+ T cells but not on CD4+ T cells of HIV+ persons. These observations suggest that type I interferons may contribute to the high levels of CD8+ T cell activation that occur during HIV infection.

  15. Polyfunctional response by ImmTAC (IMCgp100) redirected CD8+ and CD4+ T cells.

    Science.gov (United States)

    Boudousquie, Caroline; Bossi, Giovanna; Hurst, Jacob M; Rygiel, Karolina A; Jakobsen, Bent K; Hassan, Namir J

    2017-11-01

    The success of immune system-based cancer therapies depends on a broad immune response engaging a range of effector cells and mechanisms. Immune mobilizing monoclonal T cell receptors (TCRs) against cancer (ImmTAC™ molecules: fusion proteins consisting of a soluble, affinity enhanced TCR and an anti-CD3 scFv antibody) were previously shown to redirect CD8 + and CD4 + T cells against tumours. Here we present evidence that IMCgp100 (ImmTAC recognizing a peptide derived from the melanoma-specific protein, gp100, presented by HLA-A*0201) efficiently redirects and activates effector and memory cells from both CD8 + and CD4 + repertoires. Using isolated subpopulations of T cells, we find that both terminally differentiated and effector memory CD8 + T cells redirected by IMCgp100 are potent killers of melanoma cells. Furthermore, CD4 + effector memory T cells elicit potent cytotoxic activity leading to melanoma cell killing upon redirection by IMCgp100. The majority of T cell subsets belonging to both the CD8 + and CD4 + repertoires secrete key pro-inflammatory cytokines (tumour necrosis factor-α, interferon-γ, interleukin-6) and chemokines (macrophage inflammatory protein-1α-β, interferon-γ-inducible protein-10, monocyte chemoattractant protein-1). At an individual cell level, IMCgp100-redirected T cells display a polyfunctional phenotype, which is a hallmark of a potent anti-cancer response. This study demonstrates that IMCgp100 induces broad immune responses that extend beyond the induction of CD8 + T cell-mediated cytotoxicity. These findings are of particular importance because IMCgp100 is currently undergoing clinical trials as a single agent or in combination with check point inhibitors for patients with malignant melanoma. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

  16. HIV-specific CD8+ T cells: serial killers condemned to die?

    Science.gov (United States)

    Petrovas, Constantinos; Mueller, Yvonne M; Katsikis, Peter D

    2004-04-01

    An increasing body of evidence supports a key role for cytotoxic CD8+ T cells (CTL) in controlling HIV infection. Although a vigorous HIV-specific CD8+ T cell response is raised during the primary infection, these cells ultimately fail to control virus and prevent disease progression. The failure of CTL to control HIV infection has been attributed to a number of strategies HIV employs to evade the immune system. Recently, intrinsic defects in the CTL themselves have been proposed to contribute to the failure of CTL to control HIV. HIV-specific CD8+ T cells differ in their effector/memory phenotype from other virus-specific CD8+ T cells indicating that their differentiation status differs. This altered differentiation may affect effector functions as well as homing properties of these cells. Other studies have indicated that activation of HIV-specific CTL may be impaired and this contributes to their dysfunction. The effector function of these CTL may also be affected. There are conflicting reports about their ability to kill, whereas IFNgamma production does not appear to be impaired in these cells. In this review we focus on recent work indicating that apoptosis may be an important mechanism through which HIV evades the CTL response. In particular, HIV-specific CD8+ T cells are highly susceptible to CD95/Fas-induced apoptosis. This leads to the hypothesis that virus-specific cytotoxic T cells can be eliminated upon binding CD95L/FasL on HIV-infected cells. Understanding the intrinsic defects of CTL in HIV infection could lead to new therapeutic strategies and optimized vaccination protocols that enhance the HIV-specific cytotoxic response.

  17. CD4+, CD8+, CD3+ cell counts and CD4+/CD8+ ratio among patients with mycobacterial diseases (leprosy, tuberculosis), HIV infections, and normal healthy adults: a comparative analysis of studies in different regions of India.

    Science.gov (United States)

    Hussain, Tahziba; Kulshreshtha, K K; Yadav, V S; Katoch, Kiran

    2015-01-01

    In this study, we estimated the CD4+, CD8+, CD3+ cell counts and the CD4/CD8 ratio among normal healthy controls (adults and children), leprosy patients (without any complications and during reactional states), TB patients (with and without HIV), and HIV-positive patients (early infection and full-blown AIDS) and correlated the changes with disease progression. In our study, it was observed that among adults, CD4+ cell counts ranged from 518-1098, CD8+ from 312-952, whereas CD4/CD8 ratio from 0.75-2.30. Among children, both CD4+ and CD8+ cells were more and the CD4/CD8 ratio varied from 0.91-3.17. With regard to leprosy patients, we observed that CD4+ and CD8+ cell counts were lower among PB (pauci-bacillary) and MB (multi-bacillary) patients. CD4/CD8 ratio was 0.99 ± 0.28 among PB patients while the ratio was lower, 0.78 ± 0.20, among MB patients. CD4+ cell counts were raised during RR (reversal reactions) and ENL (erythema nodosum leprosum) among the PB and MB patients whereas the CD8+ cell counts were lower among PB and MB patients. CD4/CD8 ratio doubled during reactional episodes of RR and ENL. Among the HIV-negative tuberculosis (TB) patients, both the CD4+ and CD8+ cell counts were found to be less and the CD4/CD8 ratio varied between 0.53-1.75. Among the HIV-positive TB patients and HIV-positive patients, both the CD4+ and CD8+ cells were very less and ratio drops significantly. In the initial stages of infection, as CD4+ counts drop, an increase in the CD8+ cell counts was observed and the ratio declines. In full-blown cases, CD4+ cell counts were very low, 3-4 to 54 cells, CD8+ cells from 12-211 and the ratio drops too low. This study is the first of its kind in this region of the country and assumes importance since no other study has reported the values of CD4+ and CD8+ T-lymphocyte counts among patients with mycobacterial diseases (leprosy and TB), HIV infections along with normal healthy individuals of the region, and correlation with clinical

  18. Partial reconstitution of virus-specific memory CD8+ T cells following whole body γ-irradiation

    International Nuclear Information System (INIS)

    Grayson, Jason M.; Laniewski, Nathan G.; Holbrook, Beth C.

    2006-01-01

    CD8 + memory T cells are critical in providing immunity to viral infection. Previous studies documented that antigen-specific CD8 + memory T cells are more resistant to radiation-induced apoptosis than naive T cells. Here, we determined the number and in vivo function of memory CD8 + T cells as immune reconstitution progressed following irradiation. Immediately following irradiation, the number of memory CD8 + T cells declined 80%. As reconstitution progressed, the number of memory cells reached a zenith at 33% of pre-irradiation levels, and was maintained for 120 days post-irradiation. In vitro, memory CD8 + T cells were able to produce cytokines at all times post-irradiation, but when adoptively transferred, they were not able to expand upon rechallenge immediately following irradiation, but regained this ability as reconstitution progressed. When proliferation was examined in vitro, irradiated memory CD8 + T cells were able to respond to mitogenic growth but were unable to divide

  19. Comparison of Vaccine-Induced Effector CD8 T Cell Responses Directed against Self- and Non-Self-Tumor Antigens

    DEFF Research Database (Denmark)

    Pedersen, Sara R; Sørensen, Maria R; Buus, Søren

    2013-01-01

    It is generally accepted that CD8 T cells play a major role in tumor control, yet vaccination aimed at eliciting potent CD8 T cell responses are rarely efficient in clinical trials. To try and understand why this is so, we have generated potent adenoviral vectors encoding the endogenous tumor Ags...... that low avidity of the self-TA-specific CD8 T cells may represent a major obstacle for efficient immunotherapy of cancer....

  20. Detailed analysis of Epstein–Barr virus-specific CD4+ and CD8+ T cell responses during infectious mononucleosis

    Science.gov (United States)

    Scherrenburg, J; Piriou, E R W A N; Nanlohy, N M; van Baarle, D

    2008-01-01

    We studied simultaneously Epstein–Barr virus (EBV)-specific CD4+ and CD8+ T cell responses during and after infectious mononucleosis (IM), using a previously described 12-day stimulation protocol with EBNA1 or BZLF1 peptide pools. Effector function of EBV-specific T cells was determined after restimulation by measuring intracellular interferon-γ production. During IM, BZLF1-specifc CD4+ T cell responses were dominant compared with CD8+ T cell responses. EBNA1-specific CD4+ and CD8+ T cell responses were low and remained similar for 6 months. However, 6 months after IM, BZLF1-specific CD4+ T cell responses had declined, but CD8+ T cell responses had increased. At diagnosis, EBV-specific CD8+ T cells as studied by human leucocyte antigen class I tetramer staining comprised a tetramerbrightCD8bright population consisting mainly of CD27+ memory T cells and a tetramerdimCD8dim population consisting primarily of CD27- effector T cells. The remaining EBV-specific CD8+ T cell population 6 months after the diagnosis of IM consisted mainly of tetramerbrightCD8bright CD27+ T cells, suggesting preferential preservation of memory T cells after contraction of the EBV-specific T cell pool. PMID:18549439

  1. A Critical Role of IL-21-Induced BATF in Sustaining CD8-T-Cell-Mediated Chronic Viral Control

    Directory of Open Access Journals (Sweden)

    Gang Xin

    2015-11-01

    Full Text Available Control of chronic viral infections by CD8 T cells is critically dependent on CD4 help. In particular, helper-derived IL-21 plays a key role in sustaining the CD8 T cell response; however, the molecular pathways by which IL-21 sustains CD8 T cell immunity remain unclear. We demonstrate that IL-21 causes a phenotypic switch of transcription factor expression in CD8 T cells during chronic viral infection characterized by sustained BATF expression. Importantly, BATF expression during chronic infection is both required for optimal CD8 T cell persistence and anti-viral effector function and sufficient to rescue “unhelped” CD8 T cells. Mechanistically, BATF sustains the response by cooperating with IRF4, an antigen-induced transcription factor that is also critically required for CD8 T cell maintenance, to preserve Blimp-1 expression and thereby sustain CD8 T cell effector function. Collectively, these data suggest that CD4 T cells “help” the CD8 response during chronic infection via IL-21-induced BATF expression.

  2. The role of CD4 and CD8 T cells in human cutaneous leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Claudia Ida Brodskyn

    2014-09-01

    Full Text Available Leishmaniasis, caused by infection with parasites of the Leishmania genus, affects millions of individuals worldwide. This disease displays distinct clinical manifestations ranging from self-healing skin lesions to severe tissue damage. The control of Leishmania infection is dependent on cellular immune mechanisms, and evidence has shown that CD4 and CD8 T lymphocytes play different roles in the outcome of leishmaniasis. Although the presence of CD4 T cells is important for controlling parasite growth, the results in the literature suggest that the inflammatory response elicited by these cells could contribute to the pathogenesis of lesions. However, recent studies on CD8 T lymphocytes show that these cells are mainly involved in tissue damage through cytotoxic mechanisms. In this review, we focus on the recent advances in the study of the human adaptive immunological response in the pathogenesis of tegumentary leishmaniasis.

  3. LOCAL IMMUNITY BY TISSUE-RESIDENT CD8+ MEMORY T CELLS

    Directory of Open Access Journals (Sweden)

    Thomas eGebhardt

    2012-11-01

    Full Text Available Microbial infection primes a CD8+ cytotoxic T cell response that gives rise to a long-lived population of circulating memory cells able to provide protection against systemic reinfection. Despite this, effective CD8+ T cell surveillance of barrier tissues such as skin and mucosa typically wanes with time, resulting in limited T cell-mediated protection in these peripheral tissues. However, recent evidence suggests that a specialized subset of CD103+ memory T cells can permanently lodge and persist in peripheral tissues, and that these cells can compensate for the loss of peripheral immune surveillance by circulating memory T cells. Here, we review evolving concepts regarding the generation and long-term persistence of these tissue-resident memory T cells (TRM in epithelial and neuronal tissues. We further discuss the role of TRM cells in local infection control and their contribution to localized immune phenomena, in both mice and humans.

  4. Differential Impact of In Vivo CD8+ T Lymphocyte Depletion in Controller versus Progressor Simian Immunodeficiency Virus-Infected Macaques.

    Science.gov (United States)

    Chowdhury, Ankita; Hayes, Timothy L; Bosinger, Steven E; Lawson, Benton O; Vanderford, Thomas; Schmitz, Joern E; Paiardini, Mirko; Betts, Michael; Chahroudi, Ann; Estes, Jacob D; Silvestri, Guido

    2015-09-01

    Numerous studies have demonstrated that CD8(+) T lymphocytes suppress virus replication during human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection. However, the mechanisms underlying this activity of T cells remain incompletely understood. Here, we conducted CD8(+) T lymphocyte depletion in 15 rhesus macaques (RMs) infected intravenously (i.v.) with SIVmac239. At day 70 postinfection, the animals (10 progressors with high viremia and 5 controllers with low viremia) were CD8 depleted by i.v. administration of the antibody M-T807R1. As expected, CD8 depletion resulted in increased virus replication, more prominently in controllers than progressors, which correlated inversely with predepletion viremia. Of note, the feature of CD8(+) T lymphocyte predepletion that correlated best with the increase in viremia postdepletion was the level of CD8(+) T-bet(+) lymphocytes. We next found that CD8 depletion resulted in a homogenous increase of SIV RNA in superficial and mesenteric lymph nodes, spleen, and the gastrointestinal tract of both controllers and progressors. Interestingly, the level of SIV DNA increased postdepletion in both CD4(+) central memory T lymphocytes (TCM) and CD4(+) effector memory T lymphocytes (TEM) in progressor RMs but decreased in the CD4(+) TCM of 4 out of 5 controllers. Finally, we found that CD8 depletion is associated with a greater increase in CD4(+) T lymphocyte activation (measured by Ki-67 expression) in controllers than in progressors. Overall, these data reveal a differential impact of CD8(+) T lymphocyte depletion between controller and progressor SIV-infected RMs, emphasizing the complexity of the in vivo antiviral role of CD8(+) T lymphocytes. In this study, we further dissect the impact of CD8(+) T lymphocytes on HIV/SIV replication during SIV infection. CD8(+) T lymphocyte depletion leads to a relatively homogenous increase in viral replication in peripheral blood and tissues. CD8(+) T lymphocyte depletion

  5. CD4(+)CD25(+)Tregs express an increased LAG-3 and CTLA-4 in anterior chamber-associated immune deviation

    NARCIS (Netherlands)

    Zhu, X.F.; Yang, P.Z.; Zhou, H.Y.; Li, B.; Huang, X.K.; Meng, Q.L.; Wang, L.; Kijlstra, A.

    2007-01-01

    Background Regulatory CD4+CD25+ T cells have been proven to be essential for maintenance of peripheral tolerance and autoimmune diseases. ACAID is a model of immune privilege in the eye. Relatively little is known about the role and phenotype of these regulatory CD4+CD25+ T cells in ACAID. Methods

  6. CD4+RORγt++ and Tregs in a Mouse Model of Diet-Induced Nonalcoholic Steatohepatitis

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    Luisa Vonghia

    2015-01-01

    Full Text Available Background and Aims. Inflammatory mediators that cross-talk in different metabolically active organs are thought to play a crucial role in the pathogenesis of Nonalcoholic Steatohepatitis (NASH. This study was aimed at investigating the CD4+RORγt+ T-helper cells and their counterpart, the CD4+CD25+FOXP3+ regulatory T cells in the liver, subcutaneous adipose tissue (SAT, and abdominal adipose tissue (AAT in a high fat diet (HFD mouse model. Methods. C57BL6 mice were fed a HFD or a normal diet (ND. Liver enzymes, metabolic parameters, and liver histology were assessed. The expression of CD4+RORγt+ cells and regulatory T cells in different organs (blood, liver, AAT, and SAT were analyzed by flow cytometry. Cytokine and adipokine tissue expression were studied by RT-PCR. Results. Mice fed a HFD developed NASH and metabolic alterations compared to normal diet. CD4+RORγt++ cells were significantly increased in the liver and the AAT while an increase of regulatory T cells was observed in the SAT of mice fed HFD compared to ND. Inflammatory cytokines were also upregulated. Conclusions. CD4+RORγt++ cells and regulatory T cells are altered in NASH with a site-specific pattern and correlate with the severity of the disease. These site-specific differences are associated with increased cytokine expression.

  7. CMV-specific CD8 T Cell Differentiation and Localization: Implications for Adoptive Therapies

    Directory of Open Access Journals (Sweden)

    Corinne J Smith

    2016-09-01

    Full Text Available Human cytomegalovirus (HCMV is a ubiquitous virus that causes chronic infection, and thus is one of the most common infectious complications of immune suppression. Adoptive transfer of HCMV-specific T cells has emerged as an effective method to reduce the risk for HCMV infection and/or reactivation by restoring immunity in transplant recipients. However, the CMV-specific CD8+ T cell response is comprised of a heterogenous mixture of subsets with distinct functions and localization and it is not clear if current adoptive immunotherapy protocols can reconstitute the full spectrum of CD8+ T cell immunity. The aim of this review is to briefly summarize the role of these T cell subsets in CMV immunity and to describe how current adoptive immunotherapy practices might affect their reconstitution in patients. The bulk of the CMV-specific CD8+ T cell population is made up of terminally differentiated effector T cells with immediate effector function and a short life span. Self-renewing memory T cells within the CMV-specific population retain the capacity to expand and differentiate upon challenge and are important for the long-term persistence of the CD8+ T cell response. Finally mucosal organs, which are frequent sites of CMV reactivation, are primarily inhabited by tissue resident memory T cells, which do not recirculate. Future work on adoptive transfer strategies may need to focus on striking a balance between the formation of these subsets to ensure the development of long lasting and protective immune responses that can access the organs affected by CMV disease.

  8. Clinicopathologic features of myositis patients with CD8-MHC-1 complex pathology.

    Science.gov (United States)

    Ikenaga, Chiseko; Kubota, Akatsuki; Kadoya, Masato; Taira, Kenichiro; Uchio, Naohiro; Hida, Ayumi; Maeda, Meiko Hashimoto; Nagashima, Yu; Ishiura, Hiroyuki; Kaida, Kenichi; Goto, Jun; Tsuji, Shoji; Shimizu, Jun

    2017-09-05

    To determine the clinical features of myositis patients with the histopathologic finding of CD8-positive T cells invading non-necrotic muscle fibers expressing major histocompatibility complex class 1 (CD8-MHC-1 complex), which is shared by polymyositis (PM) and inclusion body myositis (IBM), in relation to the p62 immunostaining pattern of muscle fibers. All 93 myositis patients with CD8-MHC-1 complex who were referred to our hospital from 1993 to 2015 were classified on the basis of the European Neuromuscular Center (ENMC) diagnostic criteria for IBM (Rose, 2013) or PM (Hoogendijk, 2004) and analyzed. The 93 patients included were 17 patients with PM, 70 patients with IBM, and 6 patients who neither met the criteria for PM nor IBM in terms of muscle weakness distribution (unclassifiable group). For these PM, IBM, and unclassifiable patients, their mean ages at diagnosis were 63, 70, and 64 years; autoimmune disease was present in 7 (41%), 13 (19%), and 4 (67%); hepatitis C virus infection was detected in 0%, 13 (20%), and 2 (33%); and p62 was immunopositive in 0%, 66 (94%), and 2 (33%), respectively. Of the treated patients, 11 of 16 PM patients and 4 of 6 p62-immunonegative patients in the unclassifiable group showed responses to immunotherapy, whereas all 44 patients with IBM and 2 p62-immunopositive patients in the unclassifiable group were unresponsive to immunotherapy. CD8-MHC-1 complex is present in patients with PM, IBM, or unclassifiable group. The data may serve as an argument for a trial of immunosuppressive treatment in p62-immunonegative patients with unclassifiable myositis. © 2017 American Academy of Neurology.

  9. Genetic adjuvantation of recombinant MVA with CD40L potentiates CD8 T cell mediated immunity

    Directory of Open Access Journals (Sweden)

    Henning eLauterbach

    2013-08-01

    Full Text Available Modified vaccinia Ankara (MVA is a safe and promising viral vaccine vector that is currently investigated in several clinical and pre-clinical trials. In contrast to inactivated or sub-unit vaccines, MVA is able to induce strong humoral as well as cellular immune responses. In order to further improve its CD8 T cell inducing capacity, we genetically adjuvanted MVA with the coding sequence of murine CD40L, a member of the tumor necrosis factor (TNF superfamily. Immunization of mice with this new vector led to strongly enhanced primary and memory CD8 T cell responses. Concordant with the enhanced CD8 T cell response, we could detect stronger activation of dendritic cells and higher systemic levels of innate cytokines (including IL-12p70 early after immunization. Interestingly, acquisition of memory characteristics (i.e., IL-7R expression was accelerated after immunization with MVA-CD40L in comparison to non-adjuvanted MVA. Furthermore, the generated CTLs also showed improved functionality as demonstrated by intracellular cytokine staining and in vivo killing activity. Importantly, the superior CTL response after a single MVA-CD40L immunization was able to protect B cell deficient mice against a fatal infection with ectromelia virus. Taken together, we show that genetic adjuvantation of MVA can change strength, quality and functionality of innate and adaptive immune responses. These data should facilitate a rational vaccine design with a focus on rapid induction of large numbers of CD8 T cells able to protect against specific diseases.

  10. Induction of Mucosal Homing Virus-Specific CD8+ T Lymphocytes by Attenuated Simian Immunodeficiency Virus

    OpenAIRE

    Cromwell, Mandy A.; Veazey, Ronald S.; Altman, John D.; Mansfield, Keith G.; Glickman, Rhona; Allen, Todd M.; Watkins, David I.; Lackner, Andrew A.; Johnson, R. Paul

    2000-01-01

    Induction of virus-specific T-cell responses in mucosal as well as systemic compartments of the immune system is likely to be a critical feature of an effective AIDS vaccine. We investigated whether virus-specific CD8+ lymphocytes induced in rhesus macaques by immunization with attenuated simian immunodeficiency virus (SIV), an approach that is highly effective in eliciting protection against mucosal challenge, express the mucosa-homing receptor α4β7 and traffic to the intestinal mucosa. SIV-...

  11. Toward the Clonotype Analysis of Alopecia Areata-Specific, Intralesional Human CD8+ T Lymphocytes.

    Science.gov (United States)

    Bertolini, Marta; Uchida, Youhei; Paus, Ralf

    2015-11-01

    Alopecia areata (AA) is an organ-restricted autoimmune disease that mainly affects the hair follicle (HF). Several findings support a key primary effector role of CD8+ T cells in the disease pathogenesis. Autoreactive CD8+ T cells are not only present in the characteristic peribulbar inflammatory cell infiltrate of lesional AA HFs but are also found to be infiltrating in lesional HF epithelium where they are thought to recognize major histocompatibility complex class I-presented (auto-)antigens. However, the latter still remain unidentified. Therefore, one key aim in AA research is to identify the clonotypes of autoaggressive, intralesional CD8+ T cells. Therapeutically, this is important (a) so that these lymphocytes can be selectively eliminated or inhibited, (b) to identify the-as yet elusive-key (auto-)antigens in AA, and/or (c) to induce peripheral tolerance against the latter. Therefore, we have recently embarked on a National Alopecia Areata Foundation-supported project that attempts to isolate disease-specific, intralesional CD8+ T cells from AA skin in order to determine their TCR clonotype, using two complementary strategies. The first method is based on the enzymatic skin digestion from lesional AA skin, followed by either MACS technology and single-cell picking or FACS cell sorting, while the second method on laser microdissection. The identification of disease-specific TCRs can serve as a basis for specific AA immunotherapy along the lines sketched above and may possibly also provide prognostic biomarkers. If successful, this research strategy promises to permit, at long last, the causal therapy of AA.

  12. Functions of NKG2D in CD8+ T cells: an opportunity for immunotherapy.

    Science.gov (United States)

    Prajapati, Kushal; Perez, Cynthia; Rojas, Lourdes Beatriz Plaza; Burke, Brianna; Guevara-Patino, Jose A

    2018-02-05

    Natural killer group 2 member D (NKG2D) is a type II transmembrane receptor. NKG2D is present on NK cells in both mice and humans, whereas it is constitutively expressed on CD8 + T cells in humans but only expressed upon T-cell activation in mice. NKG2D is a promiscuous receptor that recognizes stress-induced surface ligands. In NK cells, NKG2D signaling is sufficient to unleash the killing response; in CD8 + T cells, this requires concurrent activation of the T-cell receptor (TCR). In this case, the function of NKG2D is to authenticate the recognition of a stressed target and enhance TCR signaling. CD28 has been established as an archetype provider of costimulation during T-cell priming. It has become apparent, however, that signals from other costimulatory receptors, such as NKG2D, are required for optimal T-cell function outside the priming phase. This review will focus on the similarities and differences between NKG2D and CD28; less well-described characteristics of NKG2D, such as the potential role of NKG2D in CD8 + T-cell memory formation, cancer immunity and autoimmunity; and the opportunities for targeting NKG2D in immunotherapy.Cellular and Molecular Immunology advance online publication, 5 February 2018; doi:10.1038/cmi.2017.161.

  13. Lower percentage of CD8+ T cells in peripheral blood of patients with sporotrichosis.

    Science.gov (United States)

    Zhu, Mingji; Xu, Yaqin; An, Lin; Jiang, Jinlan; Zhang, Xu; Jiang, Rihua

    2016-07-01

    To characterize the peripheral immunity and immunity response of patients with sporotrichosis, in this study we determined the lymphocyte subsets in the peripheral blood of Chinese patients with sporotrichosis. In this retrospective study, peripheral blood was collected from 69 sporotrichosis patients (37, fixed cutaneous form; 32 lymphocutaneous) and 66 healthy controls. Lymphocyte subsets were analyzed using flow cytometry. Compared to controls, the percentage of CD8+ T cells was lower in sporotrichosis patients. The percentage of CD8+ T cells in peripheral blood tended to become lower with disease duration and disease severity, although the difference was not statistically significant for either acute, subacute and chronic patients or fixed cutaneous and lymphocutaneous patients. Our data indicate that the decrease of CD8+ T cells in peripheral blood of patients with sporotrichosis is associated with disease severity, although the difference was not statistically significant for either duration or clinical forms of the disease. Combining antifungal agents and immunomodulators in patients with long disease duration and lymphocutaneous may be more beneficial than antifungal monotherapy. Copyright © 2016. Published by Elsevier Inc.

  14. High affinity soluble ILT2 receptor: a potent inhibitor of CD8(+) T cell activation.

    Science.gov (United States)

    Moysey, Ruth K; Li, Yi; Paston, Samantha J; Baston, Emma E; Sami, Malkit S; Cameron, Brian J; Gavarret, Jessie; Todorov, Penio; Vuidepot, Annelise; Dunn, Steven M; Pumphrey, Nicholas J; Adams, Katherine J; Yuan, Fang; Dennis, Rebecca E; Sutton, Deborah H; Johnson, Andy D; Brewer, Joanna E; Ashfield, Rebecca; Lissin, Nikolai M; Jakobsen, Bent K

    2010-12-01

    Using directed mutagenesis and phage display on a soluble fragment of the human immunoglobulin super-family receptor ILT2 (synonyms: LIR1, MIR7, CD85j), we have selected a range of mutants with binding affinities enhanced by up to 168,000-fold towards the conserved region of major histocompatibility complex (MHC) class I molecules. Produced in a dimeric form, either by chemical cross-linking with bivalent polyethylene glycol (PEG) derivatives or as a genetic fusion with human IgG Fc-fragment, the mutants exhibited a further increase in ligand-binding strength due to the avidity effect, with resident half-times (t(1/2)) on the surface of MHC I-positive cells of many hours. The novel compounds antagonized the interaction of CD8 co-receptor with MHC I in vitro without affecting the peptide-specific binding of T-cell receptors (TCRs). In both cytokine-release assays and cell-killing experiments the engineered receptors inhibited the activation of CD8(+) cytotoxic T lymphocytes (CTLs) in the presence of their target cells, with subnanomolar potency and in a dose-dependent manner. As a selective inhibitor of CD8(+) CTL responses, the engineered high affinity ILT2 receptor presents a new tool for studying the activation mechanism of different subsets of CTLs and could have potential for the development of novel autoimmunity therapies.

  15. 1Protein Energy Malnutrition Impairs Homeostatic Proliferation of Memory CD8 T cells

    Science.gov (United States)

    Iyer, Smita S.; Chatraw, Janel Hart; Tan, Wendy G.; Wherry, E. John; Becker, Todd C.; Ahmed, Rafi; Kapasi, Zoher F.

    2011-01-01

    Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. Here we show that protein energy malnutrition (PEM) induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate-protein (AP) fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV) immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that PEM caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. While antigen-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less-responsive to poly(I:C)-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13 resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals. PMID:22116826

  16. Protein energy malnutrition impairs homeostatic proliferation of memory CD8 T cells.

    Science.gov (United States)

    Iyer, Smita S; Chatraw, Janel Hart; Tan, Wendy G; Wherry, E John; Becker, Todd C; Ahmed, Rafi; Kapasi, Zoher F

    2012-01-01

    Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. In this study, we show that protein-energy malnutrition induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate protein (AP)-fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV)-immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that protein-energy malnutrition caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. Whereas Ag-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less responsive to polyinosinic-polycytidylic acid-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13, resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals.

  17. Activated iNKT cells promote memory CD8+ T cell differentiation during viral infection.

    Directory of Open Access Journals (Sweden)

    Emma C Reilly

    Full Text Available α-Galactosylceramide (α-GalCer is the prototypical lipid ligand for invariant NKT cells. Recent studies have proposed that α-GalCer is an effective adjuvant in vaccination against a range of immune challenges, however its mechanism of action has not been completely elucidated. A variety of delivery methods have been examined including pulsing dendritic cells with α-GalCer to optimize the potential of α-GalCer. These methods are currently being used in a variety of clinical trials in patients with advanced cancer but cannot be used in the context of vaccine development against pathogens due to their complexity. Using a simple delivery method, we evaluated α-GalCer adjuvant properties, using the mouse model for cytomegalovirus (MCMV. We measured several key parameters of the immune response to MCMV, including inflammation, effector, and central memory CD8(+ T cell responses. We found that α-GalCer injection at the time of the infection decreases viral titers, alters the kinetics of the inflammatory response, and promotes both increased frequencies and numbers of virus-specific memory CD8(+ T cells. Overall, our data suggest that iNKT cell activation by α-GalCer promotes the development of long-term protective immunity through increased fitness of central memory CD8(+ T cells, as a consequence of reduced inflammation.

  18. CMV driven CD8(+) T-cell activation is associated with acute rejection in lung transplantation.

    Science.gov (United States)

    Roux, Antoine; Mourin, Gisèle; Fastenackels, Solène; Almeida, Jorge R; Iglesias, Maria Candela; Boyd, Anders; Gostick, Emma; Larsen, Martin; Price, David A; Sacre, Karim; Douek, Daniel C; Autran, Brigitte; Picard, Clément; Miranda, Sandra de; Sauce, Delphine; Stern, Marc; Appay, Victor

    2013-07-01

    Lung transplantation is the definitive treatment for terminal respiratory disease, but the associated mortality rate is high. Acute rejection of the transplanted lung is a key determinant of adverse prognosis. Furthermore, an epidemiological relationship has been established between the occurrence of acute lung rejection and cytomegalovirus infection. However, the reasons for this association remain unclear. Here, we performed a longitudinal characterization of CMV-specific T-cell responses and immune activation status in the peripheral blood and bronchoalveolar lavage fluid of forty-four lung transplant patients. Acute rejection was associated with high levels of cellular activation in the periphery, reflecting strong CMV-specific CD8(+) T-cell activity post-transplant. Peripheral and lung CMV-specific CD8(+) T-cell responses were very similar, and related to the presence of CMV in the transplanted organ. These findings support that activated CMV-specific CD8(+) T-cells in the lung may play a role in promoting acute rejection. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. PENINGKATAN CD8 DAN IFN-γ PADA HYPERSENSITIVITY PNEUMONITIS (HP AKIBAT PAJANAN DEBU PENGGILINGAN PADI

    Directory of Open Access Journals (Sweden)

    Isa Ma'rufi

    2017-10-01

    Full Text Available Abstrak     Masalah klinis kesehatan kerja pada pekerja penggilingan padi saat ini adalah penyakit saluran pernafasan. Penelitian ini bertujuan untuk menganalisis peningkatan CD8 dan IFN-γ pada Pneumonitis Hipersensitif (HP akibat pajanan debu penggilingan padi pada mencit  (Musmusculus BALB/C. Penelitian yang dilakukan adalah penelitian eksperimental laboratoris dengan hewan coba mencit (Musmusculus BALB/C,  rancangan penelitian yang digunakan adalah Randomized the post test only control group design. Mencit  (Musmusculus BALB/C dipajan dengan debu penggilingan padi selama empat jam/hari selama tiga puluh hari dengan konsentrasi 0.50 mg/m3, 0.75 mg/m3, 1.00 mg/m3. Variabel bebas adalah debu penggilingan padi, sedangkan variabel tergantung adalah   CD8 dan IFN-γ, serta gambaran histopatologis paru mencit, sedangkan variabel kendali adalah strain, berat badan, dan umur. Hasil penelitian menunjukkan bahwa terjadi peningkatan kadar CD8 antara kontrol dengan perlakuan, dan secara statistik  ada perbedaan yang bermakna. Kemudian terjadi peningkatan IFN-γ dan secara statistik ada perbedaan yang bermakna antara kontrol dan perlakuan pada mencit  (Musmusculus BALB/C. Hasil penelitian dapat digunakan sebagai dasar upaya pencegahan dan pemberian terapi penyakit HP lebih dini sehingga dapat meningkatkan kualitas paru.   Kata Kunci: CD8, IFN-γ,  debu penggilingan padi     Abtract   The purpose of this research was to analyze increase of CD8  and IFN-γ of Hypersensitivity Pneumonitis (HP as a result from the exposure of dust from paddy milling on mice (MusmusculusBALB/C. The research done was a laboratory experimental research with mice (MusMusculus as experimental animal.  The research design used was the post only control group design using mice (MusMusculus Balb/c as experimental animal.  Mice (Musmusculus Balb/c were exposed to dust from paddy milling for four (4 hours/day and it was done for thirty (30 days with the exposed

  20. Increased numbers of pre-existing memory CD8 T cells and decreased T-bet expression can restrain terminal differentiation of secondary effector and memory CD8 T cells1

    Science.gov (United States)

    Joshi, Nikhil S.; Cui, Weiguo; Dominguez, Claudia; Chen, Jonathan H.; Hand, Timothy W.; Kaech, Susan M.

    2011-01-01

    Memory CD8 T cells acquire TEM properties following reinfection, and may reach terminally differentiated, senescent states (“Hayflick limit”) after multiple infections. The signals controlling this process are not well understood, but we found that the degree of 2o effector and memory CD8 T cell differentiation was intimately linked to the amount of T-bet expressed upon reactivation and pre-existing memory CD8 T cell number (i.e., 1o memory CD8 T cell precursor frequency) present during secondary infection. Compared to naïve cells, memory CD8 T cells were predisposed towards terminal effector (TE) cell differentiation because they could immediately respond to IL-12 and induce T-bet, even in the absence of antigen. TE cell formation following 2o or 3o infections was dependent on increased T-bet expression because T-bet+/− cells were resistant to these phenotypic changes. Larger numbers of pre-existing memory CD8 T cells limited the duration of 2o infection and the amount of IL-12 produced, and consequently, this reduced T-bet expression and the proportion of 2o TE CD8 T cells that formed. Together, these data show that, over repeated infections, memory CD8 T cell quality and proliferative fitness is not strictly determined by the number of serial encounters with antigen or cell divisions, but is a function of the CD8 T cell differentiation state, which is genetically controlled in a T-bet-dependent manner. This differentiation state can be modulated by pre-existing memory CD8 T cell number and the intensity of inflammation during reinfection. These results have important implications for vaccinations involving prime-boost strategies. PMID:21930973

  1. Blocking of PDL-1 interaction enhances primary and secondary CD8 T cell response to herpes simplex virus-1 infection.

    Directory of Open Access Journals (Sweden)

    Rudragouda Channappanavar

    Full Text Available The blocking of programmed death ligand-1 (PDL-1 has been shown to enhance virus-specific CD8 T cell function during chronic viral infections. Though, how PDL-1 blocking at the time of priming affects the quality of CD8 T cell response to acute infections is not well understood and remains controversial. This report demonstrates that the magnitude of the primary and secondary CD8 T cell responses to herpes simplex virus-1 (HSV-1 infection is subject to control by PDL-1. Our results showed that after footpad HSV-1 infection, PD-1 expression increases on immunodominant SSIEFARL peptide specific CD8 T cells. Additionally, post-infection, the level of PDL-1 expression also increases on CD11c+ dendritic cells. Intraperitoneal administration of anti-PDL-1 monoclonal antibody given one day prior to and three days after cutaneous HSV-1 infection, resulted in a marked increase in effector and memory CD8 T cell response to SSIEFARL peptide. This was shown by measuring the quantity and quality of SSIEFARL-specific CD8 T cells by making use of ex-vivo assays that determine antigen specific CD8 T cell function, such as intracellular cytokine assay, degranulation assay to measure cytotoxicity and viral clearance. Our results are discussed in terms of the beneficial effects of blocking PDL-1 interactions, while giving prophylactic vaccines, to generate a more effective CD8 T cell response to viral infection.

  2. Properties of HTLV-I transformed CD8+ T-cells in response to HIV-1 infection.

    Science.gov (United States)

    Gulzar, N; Shroff, A; Buberoglu, B; Klonowska, D; Kim, J E; Copeland, K F T

    2010-10-25

    HIV-1 infection studies of primary CD8(+) T-cells are hampered by difficulty in obtaining a significant number of targets for infection and low levels of productive infection. Further, there exists a paucity of CD8-expressing T-cell lines to address questions pertaining to the study of CD8(+) T-cells in the context of HIV-1 infection. In this study, a set of CD8(+) T-cell clones were originated through HTLV-I transformation in vitro, and the properties of these cells were examined. The clones were susceptible to T-cell tropic strains of the virus and exhibited HIV-1 production 20-fold greater than primary CD4(+) T-cells. Productive infection resulted in a decrease in expression of CD8 and CXCR4 molecules on the surface of the CD8(+) T-cell clones and antibodies to these molecules abrogated viral binding and replication. These transformed cells provide an important tool in the study of CD8(+) T-cells and may provide important insights into the mechanism(s) behind HIV-1 induced CD8(+) T-cell dysfunction. Copyright © 2010 Elsevier Inc. All rights reserved.

  3. miR-150 Regulates Memory CD8 T Cell Differentiation via c-Myb

    Directory of Open Access Journals (Sweden)

    Zeyu Chen

    2017-09-01

    Full Text Available MicroRNAs play an important role in T cell responses. However, how microRNAs regulate CD8 T cell memory remains poorly defined. Here, we found that miR-150 negatively regulates CD8 T cell memory in vivo. Genetic deletion of miR-150 disrupted the balance between memory precursor and terminal effector CD8 T cells following acute viral infection. Moreover, miR-150-deficient memory CD8 T cells were more protective upon rechallenge. A key circuit whereby miR-150 repressed memory CD8 T cell development through the transcription factor c-Myb was identified. Without miR-150, c-Myb was upregulated and anti-apoptotic targets of c-Myb, such as Bcl-2 and Bcl-xL, were also increased, suggesting a miR-150-c-Myb survival circuit during memory CD8 T cell development. Indeed, overexpression of non-repressible c-Myb rescued the memory CD8 T cell defects caused by overexpression of miR-150. Overall, these results identify a key role for miR-150 in memory CD8 T cells through a c-Myb-controlled enhanced survival circuit.

  4. T-bet and Eomes Are Differentially Linked to the Exhausted Phenotype of CD8+T Cells in HIV Infection

    DEFF Research Database (Denmark)

    Buggert, Marcus; Tauriainen, Johanna; Yamamoto, Takuya

    2014-01-01

    CD8+ T cell exhaustion represents a major hallmark of chronic HIV infection. Two key transcription factors governing CD8+ T cell differentiation, T-bet and Eomesodermin (Eomes), have previously been shown in mice to differentially regulate T cell exhaustion in part through direct modulation of PD...

  5. Characteristics of CD8+ T cell subsets in Chinese patients with chronic HIV infection during initial ART.

    Science.gov (United States)

    Jiao, Yanmei; Hua, Wei; Zhang, Tong; Zhang, Yonghong; Ji, Yunxia; Zhang, Hongwei; Wu, Hao

    2011-03-25

    CD8+ T cells may play an important role in protecting against HIV. However, the changes of CD8+ T cell subsets during early period of ART have not been fully studied. Twenty-one asymptomatic treatment-naive HIV-infected patients with CD4 T+ cells less than 350 cells/μl were enrolled in the study. Naïve, central memory(CM), effective memory(EM) and terminally differentiated effector (EMRA) CD8+ cell subsets and their activation and proliferation subsets were evaluated in blood samples collected at base line, and week 2, 4, 8 and 12 of ART. The total CD8+ T cells declined and the Naïve and CM subsets had a tendency of increase. Activation levels of all CD8+ T cell subsets except EMRA subset decreased after ART. However, proliferation levels of total CD8+ T cells, EMRA, EM and CM subsets increased at the first 4 weeks of ART, then decreased. Proliferation level of the naïve cells decreased after ART. The changes of CD8+ T cell subsets during initial ART are complex. Our results display a complete phenotypical picture of CD8+ cell subsets during initial ART and provide insights for understanding of immune status during ART.

  6. Characteristics of CD8+ T cell subsets in Chinese patients with chronic HIV infection during initial ART

    Directory of Open Access Journals (Sweden)

    Zhang Hongwei

    2011-03-01

    Full Text Available Abstract Background CD8+ T cells may play an important role in protecting against HIV. However, the changes of CD8+ T cell subsets during early period of ART have not been fully studied. Methods Twenty-one asymptomatic treatment-naive HIV-infected patients with CD4 T+ cells less than 350 cells/μl were enrolled in the study. Naïve, central memory(CM, effective memory(EM and terminally differentiated effector (EMRA CD8+ cell subsets and their activation and proliferation subsets were evaluated in blood samples collected at base line, and week 2, 4, 8 and 12 of ART. Results The total CD8+ T cells declined and the Naïve and CM subsets had a tendency of increase. Activation levels of all CD8+ T cell subsets except EMRA subset decreased after ART. However, proliferation levels of total CD8+ T cells, EMRA, EM and CM subsets increased at the first 4 weeks of ART, then decreased. Proliferation level of the naïve cells decreased after ART. Conclusion The changes of CD8+ T cell subsets during initial ART are complex. Our results display a complete phenotypical picture of CD8+ cell subsets during initial ART and provide insights for understanding of immune status during ART.

  7. Batf3 and Id2 have a synergistic effect on Irf8-directed classical CD8α+ dendritic cell development

    KAUST Repository

    Jaiswal, Hemant; Kaushik, Monika; Sougrat, Rachid; Gupta, Monica; Dey, Anup; Verma, Rohit; Ozato, Keiko; Tailor, Prafullakumar B.

    2013-01-01

    model for DC development and function. Expression of Irf8 in DC9 cells led to plasmacytoid DCs and CD8α+ DC-like cells, with a concomitant increase in plasmacytoid DC- and CD8α+ DC-specific gene transcripts and induction of type I IFNs and IL12p40

  8. CD49a Expression Defines Tissue-Resident CD8+ T Cells Poised for Cytotoxic Function in Human Skin

    DEFF Research Database (Denmark)

    Cheuk, Stanley; Schlums, Heinrich; Sérézal, Irène Gallais

    2017-01-01

    with vitiligo, where melanocytes are eradicated locally, CD8+CD49a+ Trm cells that constitutively expressed perforin and granzyme B accumulated both in the epidermis and dermis. Conversely, CD8+CD49a– Trm cells from psoriasis lesions predominantly generated IL-17 responses that promote local inflammation...

  9. Viral sequestration of antigen subverts cross presentation to CD8(+ T cells.

    Directory of Open Access Journals (Sweden)

    Eric F Tewalt

    2009-05-01

    Full Text Available Virus-specific CD8(+ T cells (T(CD8+ are initially triggered by peptide-MHC Class I complexes on the surface of professional antigen presenting cells (pAPC. Peptide-MHC complexes are produced by two spatially distinct pathways during virus infection. Endogenous antigens synthesized within virus-infected pAPC are presented via the direct-presentation pathway. Many viruses have developed strategies to subvert direct presentation. When direct presentation is blocked, the cross-presentation pathway, in which antigen is transferred from virus-infected cells to uninfected pAPC, is thought to compensate and allow the generation of effector T(CD8+. Direct presentation of vaccinia virus (VACV antigens driven by late promoters does not occur, as an abortive infection of pAPC prevents production of these late antigens. This lack of direct presentation results in a greatly diminished or ablated T(CD8+ response to late antigens. We demonstrate that late poxvirus antigens do not enter the cross-presentation pathway, even when identical antigens driven by early promoters access this pathway efficiently. The mechanism mediating this novel means of viral modulation of antigen presentation involves the sequestration of late antigens within virus factories. Early antigens and cellular antigens are cross-presented from virus-infected cells, as are late antigens that are targeted to compartments outside of the virus factories. This virus-mediated blockade specifically targets the cross-presentation pathway, since late antigen that is not cross-presented efficiently enters the MHC Class II presentation pathway. These data are the first to describe an evasion mechanism employed by pathogens to prevent entry into the cross-presentation pathway. In the absence of direct presentation, this evasion mechanism leads to a complete ablation of the T(CD8+ response and a potential replicative advantage for the virus. Such mechanisms of viral modulation of antigen presentation

  10. Memory vs memory-like: The different facets of CD8+ T-cell memory in HCV infection.

    Science.gov (United States)

    Hofmann, Maike; Wieland, Dominik; Pircher, Hanspeter; Thimme, Robert

    2018-05-01

    Memory CD8 + T cells are essential in orchestrating protection from re-infection. Hallmarks of virus-specific memory CD8 + T cells are the capacity to mount recall responses with rapid induction of effector cell function and antigen-independent survival. Growing evidence reveals that even chronic infection does not preclude virus-specific CD8 + T-cell memory formation. However, whether this kind of CD8 + T-cell memory that is established during chronic infection is indeed functional and provides protection from re-infection is still unclear. Human chronic hepatitis C virus infection represents a unique model system to study virus-specific CD8 + T-cell memory formation during and after cessation of persisting antigen stimulation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Program death-1 signaling and regulatory T cells collaborate to resist the function of adoptively transferred cytotoxic T lymphocytes in advanced acute myeloid leukemia.

    Science.gov (United States)

    Zhou, Qing; Munger, Meghan E; Highfill, Steven L; Tolar, Jakub; Weigel, Brenda J; Riddle, Megan; Sharpe, Arlene H; Vallera, Daniel A; Azuma, Miyuki; Levine, Bruce L; June, Carl H; Murphy, William J; Munn, David H; Blazar, Bruce R

    2010-10-07

    Tumor-induced immune defects can weaken host immune response and permit tumor cell growth. In a systemic model of murine acute myeloid leukemia (AML), tumor progression resulted in increased regulatory T cells (Treg) and elevation of program death-1 (PD-1) expression on CD8(+) cytotoxic T cells (CTLs) at the tumor site. PD-1 knockout mice were more resistant to AML despite the presence of similar percentage of Tregs compared with wild type. In vitro, intact Treg suppression of CD8(+) T-cell responses was dependent on PD-1 expression by T cells and Tregs and PD-L1 expression by antigen-presenting cells. In vivo, the function of adoptively transferred AML-reactive CTLs was reduced by AML-associated Tregs. Anti-PD-L1 monoclonal antibody treatment increased the proliferation and function of CTLs at tumor sites, reduced AML tumor burden, and resulted in long-term survivors. Treg depletion followed by PD-1/PD-L1 blockade showed superior efficacy for eradication of established AML. These data demonstrated that interaction between PD-1 and PD-L1 can facilitate Treg-induced suppression of T-effector cells and dampen the antitumor immune response. PD-1/PD-L1 blockade coupled with Treg depletion represents an important new approach that can be readily translated into the clinic to improve the therapeutic efficacy of adoptive AML-reactive CTLs in advanced AML disease.

  12. alpha(4)beta(7) independent pathway for CD8(+) T cell-mediated intestinal immunity to rotavirus.

    Science.gov (United States)

    Kuklin, N A; Rott, L; Darling, J; Campbell, J J; Franco, M; Feng, N; Müller, W; Wagner, N; Altman, J; Butcher, E C; Greenberg, H B

    2000-12-01

    Rotavirus (RV), which replicates exclusively in cells of the small intestine, is the most important cause of severe diarrhea in young children worldwide. Using a mouse model, we show that expression of the intestinal homing integrin alpha(4)ss(7) is not essential for CD8(+) T cells to migrate to the intestine or provide immunity to RV. Mice deficient in ss7 expression (ss7(-/-)) and unable to express alpha(4)ss(7) integrin were found to clear RV as quickly as wild-type (wt) animals. Depletion of CD8(+) T cells in ss7(-/-) animals prolonged viral shedding, and transfer of immune ss7(-/-) CD8(+) T cells into chronically infected Rag-2-deficient mice resolved RV infection as efficiently as wt CD8(+) T cells. Paradoxically, alpha(4)ss(7)(hi) memory CD8(+) T cells purified from wt mice that had been orally immunized cleared RV more efficiently than alpha(4)ss(7)(low) CD8(+) T cells. We explained this apparent contradiction by demonstrating that expression of alpha(4)ss(7) on effector CD8(+) T cells depends upon the site of initial antigen exposure: oral immunization generates RV-specific CD8(+) T cells primarily of an alpha(4)ss(7)(hi) phenotype, but subcutaneous immunization yields both alpha(4)ss(7)(hi) and alpha(4)ss(7)(low) immune CD8(+) T cells with anti-RV effector capabilities. Thus, alpha(4)ss(7) facilitates normal intestinal immune trafficking to the gut, but it is not required for effective CD8(+) T cell immunity.

  13. TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15.

    Science.gov (United States)

    Villanueva, Jeanette E; Malle, Elisabeth K; Gardam, Sandra; Silveira, Pablo A; Zammit, Nathan W; Walters, Stacey N; Brink, Robert; Grey, Shane T

    2015-06-01

    In this study, a critical and novel role for TNF receptor (TNFR) associated factor 2 (TRAF2) is elucidated for peripheral CD8(+) T-cell and NKT-cell homeostasis. Mice deficient in TRAF2 only in their T cells (TRAF2TKO) show ∼40% reduction in effector memory and ∼50% reduction in naïve CD8(+) T-cell subsets. IL-15-dependent populations were reduced further, as TRAF2TKO mice displayed a marked ∼70% reduction in central memory CD8(+) CD44(hi) CD122(+) T cells and ∼80% decrease in NKT cells. TRAF2TKO CD8(+) CD44(hi) T cells exhibited impaired dose-dependent proliferation to exogenous IL-15. In contrast, TRAF2TKO CD8(+) T cells proliferated normally to anti-CD3 and TRAF2TKO CD8(+) CD44(hi) T cells exhibited normal proliferation to exogenous IL-2. TRAF2TKO CD8(+) T cells expressed normal levels of IL-15-associated receptors and possessed functional IL-15-mediated STAT5 phosphorylation, however TRAF2 deletion caused increased AKT activation. Loss of CD8(+) CD44(hi) CD122(+) and NKT cells was mechanistically linked to an inability to respond to IL-15. The reduced CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell populations in TRAF2TKO mice were rescued in the presence of high dose IL-15 by IL-15/IL-15Rα complex administration. These studies demonstrate a critical role for TRAF2 in the maintenance of peripheral CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell homeostasis by modulating sensitivity to T-cell intrinsic growth factors such as IL-15. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

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    Elena Sandalova

    Full Text Available Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR, proliferation (Ki-67/Bcl-2(low and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV. CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

  15. T-bet and Eomes are differentially linked to the exhausted phenotype of CD8+ T cells in HIV infection.

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    Marcus Buggert

    2014-07-01

    Full Text Available CD8(+ T cell exhaustion represents a major hallmark of chronic HIV infection. Two key transcription factors governing CD8(+ T cell differentiation, T-bet and Eomesodermin (Eomes, have previously been shown in mice to differentially regulate T cell exhaustion in part through direct modulation of PD-1. Here, we examined the relationship between these transcription factors and the expression of several inhibitory receptors (PD-1, CD160, and 2B4, functional characteristics and memory differentiation of CD8(+ T cells in chronic and treated HIV infection. The expression of PD-1, CD160, and 2B4 on total CD8(+ T cells was elevated in chronically infected individuals and highly associated with a T-bet(dimEomes(hi expressional profile. Interestingly, both resting and activated HIV-specific CD8(+ T cells in chronic infection were almost exclusively T-bet(dimEomes(hi cells, while CMV-specific CD8(+ T cells displayed a balanced expression pattern of T-bet and Eomes. The T-bet(dimEomes(hi virus-specific CD8(+ T cells did not show features of terminal differentiation, but rather a transitional memory phenotype with poor polyfunctional (effector characteristics. The transitional and exhausted phenotype of HIV-specific CD8(+ T cells was longitudinally related to persistent Eomes expression after antiretroviral therapy (ART initiation. Strikingly, these characteristics remained stable up to 10 years after ART initiation. This study supports the concept that poor human viral-specific CD8(+ T cell functionality is due to an inverse expression balance between T-bet and Eomes, which is not reversed despite long-term viral control through ART. These results aid to explain the inability of HIV-specific CD8(+ T cells to control the viral replication post-ART cessation.

  16. Kinetics of Epstein-Barr virus load and virus-specific CD8+ T cells in acute infectious mononucleosis.

    Science.gov (United States)

    Hoshino, Yo; Nishikawa, Kazuo; Ito, Yoshinori; Kuzushima, Kiyotaka; Kimura, Hiroshi

    2011-03-01

    During the convalescent phase of acute infectious mononucleosis (AIM), Epstein-Barr virus (EBV) load shrinks rapidly in association with a rapid decline in the number of EBV-specific CD8(+) T cells. The actual contribution of EBV-specific CD8(+) T cells in reducing EBV load, however, is not known. To clarify the impact of EBV-specific CD8(+) T cells on the contraction of EBV load in AIM, we estimated half-lives of both EBV load and EBV-specific CD8(+) T cells. Blood was serially taken from five pediatric patients with AIM during the convalescent period, including the very early phase, and both EBV load and EBV-specific CD8(+) T cell numbers were assayed. EBV load declined rapidly (half-life 1.5 d) during the first 2 weeks after onset of symptoms. This half-life was seven-fold shorter than that reported for CD27(+) memory B cells. Subsequently, the EBV load declined much more slowly, with a half-life of 38.7 d. EBV-specific CD8(+) T cell numbers also declined concomitantly with the decrease in EBV load. The half-life of EBV-specific CD8(+) T cells during first 2 weeks was 2.9 d. The number of EBV-specific CD8(+) T cells and the rate of change of viral load correlated significantly (R(2) ≥ 0.8; p ≤ 0.02). The short half-life of EBV load, together with the strong correlation between the number of EBV-specific CD8(+) T cells and the rate of change of viral load indicates an active role for EBV-specific CD8(+) T cells in elimination of EBV in AIM. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Relationship of the Content of Systemic and Endobronchial Soluble Molecules of CD25, CD38, CD8, and HLA-I-CD8 and Lung Function Parameters in COPD Patients

    Directory of Open Access Journals (Sweden)

    Nailya Kubysheva

    2017-01-01

    Full Text Available The definition of new markers of local and systemic inflammation of chronic obstructive pulmonary disease (COPD is one of the priority directions in the study of pathogenesis and diagnostic methods improvement for this disease. We investigated 91 patients with COPD and 21 healthy nonsmokers. The levels of soluble CD25, CD38, CD8, and HLA-I-CD8 molecules in the blood serum and exhaled breath condensate (EBC in moderate-to-severe COPD patients during exacerbation and stable phase were studied. An unidirectional change in the content of sCD25, sCD38, and sCD8 molecules with increasing severity of COPD was detected. The correlations between the parameters of lung function and sCD8, sCD25, and sHLA-I-CD8 levels in the blood serum and EBC were discovered in patients with severe COPD. The findings suggest a pathogenetic role of the investigated soluble molecules of the COPD development and allow considering the content of sCD8, sCD25, and sHLA-I-CD8 molecules as additional novel systemic and endobronchial markers of the progression of chronic inflammation of this disease.

  18. CD8 T cells protect adult naive mice from JEV-induced morbidity via lytic function.

    Science.gov (United States)

    Jain, Nidhi; Oswal, Neelam; Chawla, Amanpreet Singh; Agrawal, Tanvi; Biswas, Moanaro; Vrati, Sudhanshu; Rath, Satyajit; George, Anna; Bal, Vineeta; Medigeshi, Guruprasad R

    2017-02-01

    Following Japanese encephalitis virus (JEV) infection neutralizing antibodies are shown to provide protection in a significant proportion of cases, but not all, suggesting additional components of immune system might also contribute to elicit protective immune response. Here we have characterized the role of T cells in offering protection in adult mice infected with JEV. Mice lacking α/β-T cells (TCRβ-null) are highly susceptible and die over 10-18 day period as compared to the wild-type (WT) mice which are resistant. This is associated with high viral load, higher mRNA levels of proinflammatory cytokines and breach in the blood-brain-barrier (BBB). Infected WT mice do not show a breach in BBB; however, in contrast to TCRβ-null, they show the presence of T cells in the brain. Using adoptive transfer of cells with specific genetic deficiencies we see that neither the presence of CD4 T cells nor cytokines such as IL-4, IL-10 or interferon-gamma have any significant role in offering protection from primary infection. In contrast, we show that CD8 T cell deficiency is more critical as absence of CD8 T cells alone increases mortality in mice infected with JEV. Further, transfer of T cells from beige mice with defects in granular lytic function into TCRβ-null mice shows poor protection implicating granule-mediated target cell lysis as an essential component for survival. In addition, for the first time we report that γ/δ-T cells also make significant contribution to confer protection from JEV infection. Our data show that effector CD8 T cells play a protective role during primary infection possibly by preventing the breach in BBB and neuronal damage.

  19. CD8 T cells protect adult naive mice from JEV-induced morbidity via lytic function.

    Directory of Open Access Journals (Sweden)

    Nidhi Jain

    2017-02-01

    Full Text Available Following Japanese encephalitis virus (JEV infection neutralizing antibodies are shown to provide protection in a significant proportion of cases, but not all, suggesting additional components of immune system might also contribute to elicit protective immune response. Here we have characterized the role of T cells in offering protection in adult mice infected with JEV. Mice lacking α/β-T cells (TCRβ-null are highly susceptible and die over 10-18 day period as compared to the wild-type (WT mice which are resistant. This is associated with high viral load, higher mRNA levels of proinflammatory cytokines and breach in the blood-brain-barrier (BBB. Infected WT mice do not show a breach in BBB; however, in contrast to TCRβ-null, they show the presence of T cells in the brain. Using adoptive transfer of cells with specific genetic deficiencies we see that neither the presence of CD4 T cells nor cytokines such as IL-4, IL-10 or interferon-gamma have any significant role in offering protection from primary infection. In contrast, we show that CD8 T cell deficiency is more critical as absence of CD8 T cells alone increases mortality in mice infected with JEV. Further, transfer of T cells from beige mice with defects in granular lytic function into TCRβ-null mice shows poor protection implicating granule-mediated target cell lysis as an essential component for survival. In addition, for the first time we report that γ/δ-T cells also make significant contribution to confer protection from JEV infection. Our data show that effector CD8 T cells play a protective role during primary infection possibly by preventing the breach in BBB and neuronal damage.

  20. Viral Escape Mutant Epitope Maintains TCR Affinity for Antigen yet Curtails CD8 T Cell Responses.

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    Shayla K Shorter

    Full Text Available T cells have the remarkable ability to recognize antigen with great specificity and in turn mount an appropriate and robust immune response. Critical to this process is the initial T cell antigen recognition and subsequent signal transduction events. This antigen recognition can be modulated at the site of TCR interaction with peptide:major histocompatibility (pMHC or peptide interaction with the MHC molecule. Both events could have a range of effects on T cell fate. Though responses to antigens that bind sub-optimally to TCR, known as altered peptide ligands (APL, have been studied extensively, the impact of disrupting antigen binding to MHC has been highlighted to a lesser extent and is usually considered to result in complete loss of epitope recognition. Here we present a model of viral evasion from CD8 T cell immuno-surveillance by a lymphocytic choriomeningitis virus (LCMV escape mutant with an epitope for which TCR affinity for pMHC remains high but where the antigenic peptide binds sub optimally to MHC. Despite high TCR affinity for variant epitope, levels of interferon regulatory factor-4 (IRF4 are not sustained in response to the variant indicating differences in perceived TCR signal strength. The CD8+ T cell response to the variant epitope is characterized by early proliferation and up-regulation of activation markers. Interestingly, this response is not maintained and is characterized by a lack in IL-2 and IFNγ production, increased apoptosis and an abrogated glycolytic response. We show that disrupting the stability of peptide in MHC can effectively disrupt TCR signal strength despite unchanged affinity for TCR and can significantly impact the CD8+ T cell response to a viral escape mutant.

  1. Decline of influenza-specific CD8+ T cell repertoire in healthy geriatric donors

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    Ramachandra Lakshmi

    2011-08-01

    Full Text Available Abstract Background While influenza vaccination results in protective antibodies against primary infections, clearance of infection is primarily mediated through CD8+ T cells. Studying the CD8+ T cell response to influenza epitopes is crucial in understanding the disease associated morbidity and mortality especially in at risk populations such as the elderly. We compared the CD8+ T cell response to immunodominant and subdominant influenza epitopes in HLA-A2+ control, adult donors, aged 21-42, and in geriatric donors, aged 65 and older. Results We used a novel artificial Antigen Presenting Cell (aAPC based stimulation assay to reveal responses that could not be detected by enzyme-linked immunosorbent spot (ELISpot. 14 younger control donors and 12 geriatric donors were enrolled in this study. The mean number of influenza-specific subdominant epitopes per control donor detected by ELISpot was only 1.4 while the mean detected by aAPC assay was 3.3 (p = 0.0096. Using the aAPC assay, 92% of the control donors responded to at least one subdominant epitopes, while 71% of control donors responded to more than one subdominant influenza-specific response. 66% of geriatric donors lacked a subdominant influenza-specific response and 33% of geriatric donors responded to only 1 subdominant epitope. The difference in subdominant response between age groups is statistically significant (p = 0.0003. Conclusion Geriatric donors lacked the broad, multi-specific response to subdominant epitopes seen in the control donors. Thus, we conclude that aging leads to a decrease in the subdominant influenza-specific CTL responses which may contribute to the increased morbidity and mortality in older individuals.

  2. CD4(+)/CD8(+) T-lymphocyte Ratio: Effects of Rehydration before Exercise in Dehydrated Men

    Science.gov (United States)

    Greenleaf, John E.; Jackson, Catherine G. R.; Lawless, Desales

    1995-01-01

    Effects of fluid ingestion on CD4+/CD8+ T-lymphocyte cell ratios were measured in four dehydrated men (ages 30-46 yr) before and after 70 min of supine submaximal (71 % VO(sub 2max) lower extremity cycle exercise. Just before exercise, Evans blue dye was injected for measurement of plasma volume. The subjects then drank one of six fluid formulations (12 ml/kg) in 3-4 min. All six mean post-hydration (pre-exercise) CD4+/CD8+ ratios (Becton-Dickinson Fluorescence Activated Cell Sorter and FACScan Consort-30 software program were below the normal range of 1.2-1.5; mean (+/- SE) and range were 0.77 +/- 0.12 and 0.39-1.15, respectively. The post-exercise ratios increased: mean = 1.36 =/- 0.15 (P less than 0.05) and range = 0.98-1.98. Regression of mean CD4+/CD8+ ratios on mean plasma osmolality resulted in pre- and post-exercise correlation coefficients of -0.76 (P less than 0.10) and -0.92 (P less than 0.01), respectively. The decreased pre-exercise ratios (after drinking) were probably not caused by the Evans blue dye but appeared to be associated more with the stress (osmotic) of dehydration. The increased post-exercise ratios to normal levels accompanied the rehydration and were not due to the varied electrolyte and osmotic concentrations of the ingested fluids or to the varied vascular volume shifts during exercise. Thus, the level of subject hydration and plasma osmotality may be factors involved in the mechanism of immune system modulation induced by exercise.

  3. Methods of Controlling Invasive Fungal Infections Using CD8+ T Cells

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    Pappanaicken R. Kumaresan

    2018-01-01

    Full Text Available Invasive fungal infections (IFIs cause high rates of morbidity and mortality in immunocompromised patients. Pattern-recognition receptors present on the surfaces of innate immune cells recognize fungal pathogens and activate the first line of defense against fungal infection. The second line of defense is the adaptive immune system which involves mainly CD4+ T cells, while CD8+ T cells also play a role. CD8+ T cell-based vaccines designed to prevent IFIs are currently being investigated in clinical trials, their use could play an especially important role in acquired immune deficiency syndrome patients. So far, none of the vaccines used to treat IFI have been approved by the FDA. Here, we review current and future antifungal immunotherapy strategies involving CD8+ T cells. We highlight recent advances in the use of T cells engineered using a Sleeping Beauty vector to treat IFIs. Recent clinical trials using chimeric antigen receptor (CAR T-cell therapy to treat patients with leukemia have shown very promising results. We hypothesized that CAR T cells could also be used to control IFI. Therefore, we designed a CAR that targets β-glucan, a sugar molecule found in most of the fungal cell walls, using the extracellular domain of Dectin-1, which binds to β-glucan. Mice treated with D-CAR+ T cells displayed reductions in hyphal growth of Aspergillus compared to the untreated group. Patients suffering from IFIs due to primary immunodeficiency, secondary immunodeficiency (e.g., HIV, or hematopoietic transplant patients may benefit from bioengineered CAR T cell therapy.

  4. Tolerogenic interactions between CD8+ dendritic cells and NKT cells prevent rejection of bone marrow and organ grafts.

    Science.gov (United States)

    Hongo, David; Tang, Xiaobin; Zhang, Xiangyue; Engleman, Edgar G; Strober, Samuel

    2017-03-23

    The combination of total lymphoid irradiation and anti-T-cell antibodies safely induces immune tolerance to combined hematopoietic cell and organ allografts in humans. Our mouse model required host natural killer T (NKT) cells to induce tolerance. Because NKT cells normally depend on signals from CD8 + dendritic cells (DCs) for their activation, we used the mouse model to test the hypothesis that, after lymphoid irradiation, host CD8 + DCs play a requisite role in tolerance induction through interactions with NKT cells. Selective deficiency of either CD8 + DCs or NKT cells abrogated chimerism and organ graft acceptance. After radiation, the CD8 + DCs increased expression of surface molecules required for NKT and apoptotic cell interactions and developed suppressive immune functions, including production of indoleamine 2,3-deoxygenase. Injection of naive mice with apoptotic spleen cells generated by irradiation led to DC changes similar to those induced by lymphoid radiation, suggesting that apoptotic body ingestion by CD8 + DCs initiates tolerance induction. Tolerogenic CD8 + DCs induced the development of tolerogenic NKT cells with a marked T helper 2 cell bias that, in turn, regulated the differentiation of the DCs and suppressed rejection of the transplants. Thus, reciprocal interactions between CD8 + DCs and invariant NKT cells are required for tolerance induction in this system that was translated into a successful clinical protocol. © 2017 by The American Society of Hematology.

  5. Batf3 and Id2 have a synergistic effect on Irf8-directed classical CD8α+ dendritic cell development

    KAUST Repository

    Jaiswal, Hemant

    2013-11-13

    Dendritic cells (DCs) are heterogeneous cell populations represented by different subtypes, each varying in terms of gene expression patterns and specific functions. Recent studies identified transcription factors essential for the development of different DC subtypes, yet molecular mechanisms for the developmental program and functions remain poorly understood. In this study, we developed and characterized a mouse DC progenitor-like cell line, designated DC9, from Irf8-/- bone marrow cells as a model for DC development and function. Expression of Irf8 in DC9 cells led to plasmacytoid DCs and CD8α+ DC-like cells, with a concomitant increase in plasmacytoid DC- and CD8α+ DC-specific gene transcripts and induction of type I IFNs and IL12p40 following TLR ligand stimulation. Irf8 expression in DC9 cells led to an increase in Id2 and Batf3 transcript levels, transcription factors shown to be important for the development of CD8α+ DCs. We show that, without Irf8 , expression of Id2 and Batf3 was not sufficient for directing classical CD8α+ DC development. When coexpressed with Irf8, Batf3 and Id2 had a synergistic effect on classical CD8α+ DC development. We demonstrate that Irf8 is upstream of Batf3 and Id2 in the classical CD8α+ DC developmental program and define the hierarchical relationship of transcription factors important for classical CD8α+ DC development.

  6. Diet-induced obesity does not impact the generation and maintenance of primary memory CD8 T cells.

    Science.gov (United States)

    Khan, Shaniya H; Hemann, Emily A; Legge, Kevin L; Norian, Lyse A; Badovinac, Vladimir P

    2014-12-15

    The extent to which obesity compromises the differentiation and maintenance of protective memory CD8 T cell responses and renders obese individuals susceptible to infection remains unknown. In this study, we show that diet-induced obesity did not impact the maintenance of pre-existing memory CD8 T cells, including acquisition of a long-term memory phenotype (i.e., CD27(hi), CD62L(hi), KLRG1(lo)) and function (i.e., cytokine production, secondary expansion, and memory CD8 T cell-mediated protection). Additionally, obesity did not influence the differentiation and maintenance of newly evoked memory CD8 T cell responses in inbred and outbred hosts generated in response to different types of systemic (LCMV, L. monocytogenes) and/or localized (influenza virus) infections. Interestingly, the rate of naive-to-memory CD8 T cell differentiation after a peptide-coated dendritic cell immunization was similar in lean and obese hosts, suggesting that obesity-associated inflammation, unlike pathogen- or adjuvant-induced inflammation, did not influence the development of endogenous memory CD8 T cell responses. Therefore, our studies reveal that the obese environment does not influence the development or maintenance of memory CD8 T cell responses that are either primed before or after obesity is established, a surprising notion with important implications for future studies aiming to elucidate the role obesity plays in host susceptibility to infections. Copyright © 2014 by The American Association of Immunologists, Inc.

  7. Expression, purification, crystallization and preliminary X-ray diffraction analysis of rhesus macaque CD8αα homodimer

    International Nuclear Information System (INIS)

    Zong, Lili; Chen, Yong; Yan, Jinghua; Zhang, Jianhua

    2010-01-01

    CD8α exodomain protein, a crucial immune-system factor in rhesus macaque (M. mulatta), one of the best animal models for vaccine design, was assembled and crystallized. The full structure data will contribute to future studies of immune responses in rhesus macaques. As a T-cell co-receptor, CD8 binds to MHC class I molecules and plays a pivotal role in the activation of cytotoxic T lymphocytes. To date, structures of CD8 have been solved for two different mammals: human and mouse. The infection of rhesus macaques (Macaca mulatta) by simian immunodeficiency virus (SIV) is the best animal model for studying HIV. In this study, the rhesus macaque CD8 (rCD8) αα homodimer was obtained and rCD8α exodomain protein crystals were successfully obtained for further structural analysis. Diffraction data were collected to a resolution of 2.4 Å. The crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 46.52, b = 56.28, c = 82.40 Å. These data will facilitate further studies on the structural differences between these CD8 structures and the cellular immune responses of rhesus macaque

  8. Antigen sensitivity is a major determinant of CD8+ T-cell polyfunctionality and HIV-suppressive activity.

    Science.gov (United States)

    Almeida, Jorge R; Sauce, Delphine; Price, David A; Papagno, Laura; Shin, So Youn; Moris, Arnaud; Larsen, Martin; Pancino, Gianfranco; Douek, Daniel C; Autran, Brigitte; Sáez-Cirión, Asier; Appay, Victor

    2009-06-18

    CD8(+) T cells are major players in the immune response against HIV. However, recent failures in the development of T cell-based vaccines against HIV-1 have emphasized the need to reassess our basic knowledge of T cell-mediated efficacy. CD8(+) T cells from HIV-1-infected patients with slow disease progression exhibit potent polyfunctionality and HIV-suppressive activity, yet the factors that unify these properties are incompletely understood. We performed a detailed study of the interplay between T-cell functional attributes using a bank of HIV-specific CD8(+) T-cell clones isolated in vitro; this approach enabled us to overcome inherent difficulties related to the in vivo heterogeneity of T-cell populations and address the underlying determinants that synthesize the qualities required for antiviral efficacy. Conclusions were supported by ex vivo analysis of HIV-specific CD8(+) T cells from infected donors. We report that attributes of CD8(+) T-cell efficacy against HIV are linked at the level of antigen sensitivity. Highly sensitive CD8(+) T cells display polyfunctional profiles and potent HIV-suppressive activity. These data provide new insights into the mechanisms underlying CD8(+) T-cell efficacy against HIV, and indicate that vaccine strategies should focus on the induction of HIV-specific T cells with high levels of antigen sensitivity to elicit potent antiviral efficacy.

  9. Antigen and Memory CD8 T Cells: Were They Both Right?

    Directory of Open Access Journals (Sweden)

    Epelman Slava

    2007-06-01

    Full Text Available Picture yourself as a researcher in immunology. To begin your project, you ask a question: Do CD8 T cells require antigen to maintain a memory response? This question is of prime importance to numerous medical fields. In chronologic order, you digest the literature, but unfortunately, you hit a major stumbling block in the 1990s. The crux of the problem is that which so often happens in science: two well-recognized, capable groups emerge with diametrically opposed conclusions, leaving you pondering which set of wellcontrolled data to believe. Fortunately, years later, a surprising group of articles sheds light on this mystery and subtly reconciles these two positions.

  10. The CD8+ memory T-cell state of readiness is actively maintained and reversible

    OpenAIRE

    Allam, Atef; Conze, Dietrich B.; Giardino Torchia, Maria Letizia; Munitic, Ivana; Yagita, Hideo; Sowell, Ryan T.; Marzo, Amanda L.; Ashwell, Jonathan D.

    2009-01-01

    The ability of the adaptive immune system to respond rapidly and robustly upon repeated antigen exposure is known as immunologic memory, and it is thought that acquisition of memory T-cell function is an irreversible differentiation event. In this study, we report that many phenotypic and functional characteristics of antigen-specific CD8 memory T cells are lost when they are deprived of contact with dendritic cells. Under these circumstances, memory T cells reverted from G1 to the G0 cell-cy...

  11. Qualitative and quantitative analysis of adenovirus type 5 vector-induced memory CD8 T cells

    DEFF Research Database (Denmark)

    Steffensen, Maria Abildgaard; Holst, Peter Johannes; Steengaard, Sanne Skovvang

    2013-01-01

    infection with lymphocytic choriomeningitis virus. We found that localized immunization with intermediate doses of Ad vector induce a moderate number of functional CD8 T cells, which qualitatively match those found in LCMV-infected mice. Numbers of these cells may be efficiently increased by additional...... adenoviral boosting and, importantly, the generated secondary memory cells cannot be qualitatively differentiated from those induced by primary infection with replicating virus. Quantitatively, DNA priming prior to Ad-vaccination will lead to even higher numbers of memory cells. In this case, the vaccination...

  12. Alpha 4 integrin directs virus-activated CD8+ T cells to sites of infection

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Andersson, E C; Scheynius, A

    1995-01-01

    This article examines the role of VLA-4 in directing lymphocytes to sites of viral infection using the murine lymphocytic choriomeningitis virus infection (LCMV) as the model system. This virus by itself induces little or no inflammation, but in most mouse/virus strain combinations a potent T cell...... response is induced, which is associated with marked CD8+ cell-mediated inflammation. Two expressions of LCMV-induced inflammation were studied: meningitis induced by intracerebral infection and adoptive transfer of virus-specific delayed-type hypersensitivity. Our previous studies have shown that LCMV...

  13. The contribution of Chlamydia-specific CD8⁺ T cells to upper genital tract pathology.

    Science.gov (United States)

    Vlcek, Kelly R; Li, Weidang; Manam, Srikanth; Zanotti, Brian; Nicholson, Bruce J; Ramsey, Kyle H; Murthy, Ashlesh K

    2016-02-01

    Genital chlamydial infections lead to severe upper reproductive tract pathology in a subset of untreated women. We demonstrated previously that tumor necrosis factor (TNF)-α-producing CD8(+) T cells contribute significantly to chlamydial upper genital tract pathology in female mice. In addition, we observed that minimal chlamydial oviduct pathology develops in OT-1 transgenic (OT-1) mice, wherein the CD8(+) T-cell repertoire is restricted to recognition of the ovalbumin peptide Ova(257-264), suggesting that non-Chlamydia-specific CD8(+) T cells may not be responsible for chlamydial pathogenesis. In the current study, we evaluated whether antigen-specific CD8(+) T cells mediate chlamydial pathology. Groups of wild-type (WT) C57BL/6J, OT-1 mice, and OT-1 mice replete with WT CD8(+) T cells (1 × 10(6) cells per mouse intravenously) were infected intravaginally with C. muridarum (5 × 10(4) IFU/mouse). Serum total anti-Chlamydia antibody and total splenic anti-Chlamydia interferon (IFN)-γ and TNF-α responses were comparable among the three groups of animals. However, Chlamydia-specific IFN-γ and TNF-α production from purified splenic CD8(+) T cells of OT-1 mice was minimal, whereas responses in OT-1 mice replete with WT CD8(+) T cells were comparable to those in WT animals. Vaginal chlamydial clearance was comparable between the three groups of mice. Importantly, the incidence and severity of oviduct and uterine horn pathology was significantly reduced in OT-1 mice but reverted to WT levels in OT-1 mice replete with WT CD8(+) T cells. Collectively, these results demonstrate that Chlamydia-specific CD8(+) T cells contribute significantly to upper genital tract pathology.

  14. CD8+ T Cells Mediate Female-Dominant IL-4 Production and Airway Inflammation in Allergic Asthma.

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    Chihiro Ito

    Full Text Available The prevalence and severity of bronchial asthma are higher in females than in males after puberty. Although antigen-specific CD8+ T cells play an important role in the development of asthma through their suppressive effect on cytokine production, the contribution of CD8+ T cells to sex differences in asthmatic responses remains unclear. In the present study, we investigated the sex-specific effect of CD8+ T cells in the suppression of asthma using an ovalbumin mouse model of asthma. The number of inflammatory cells in bronchoalveolar lavage (BAL fluid, lung type 2 T-helper cytokine levels, and interleukin-4 (IL-4 production by bronchial lymph node cells were significantly higher in female wild-type (WT mice compared with male mice, whereas no such sex differences were observed between male and female cd8α-disrupted mice. The adaptive transfer of male, but not female, CD8+ T cells reduced the number of inflammatory cells in the recovered BAL fluid of male recipient mice, while no such sex difference in the suppressive activity of CD8+ T cells was observed in female recipient mice. Male CD8+ T cells produced higher levels of IFN-γ than female CD8+ T cells did, and this trend was associated with reduced IL-4 production by male, but not female, CD4+ T cells. Interestingly, IFN-γ receptor expression on CD4+ T cells was significantly lower in female mice than in male mice. These results suggest that female-dominant asthmatic responses are orchestrated by the reduced production of IFN-γ by CD8+ T cells and the lower expression of IFN-γ receptor on CD4+ T cells in females compared with males.

  15. CD8 apoptosis may be a predictor of T cell number normalization after immune reconstitution in HIV

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    Martinez Maria L

    2007-01-01

    Full Text Available Abstract Background As part of the Houston Vanguard study, a subset of 10 patients randomized to receive IL-2 therapy were compared to 4 patients randomized to not receive IL-2, for markers of T cell activation and death during the first three cycles of IL-2. All patients were treated with combination antiretroviral therapy (ART and were virally suppressed. The purpose of the study was to examine the role of CD8+ T cell death in responses to ART and IL-2 therapy. Methods Lymphocytes were examined at Day 0, 5 and 30 days during three cycles of IL-2 therapy. CD25, CD38, HLA-DR expression and annexin (cell death were examined on CD4 and CD8 subpopulations. Follow up studies examined CD4 levels and CD4:CD8 reconstitution after 6 years using both univariant and multivariate analyses. Results Human lymphocytes responded to IL-2 therapy by upregulation of CD25 on CD4+ T cells, leading to an increase in CD4 cell counts. CD8+ T cells did not increase CD25 expression, but upregulated activation antigens (CD38 and DR and had increased death. At baseline, 7 of the 14 patients had high CD8+ T cell apoptosis (mean 17.0% ± 6.0. We did an exploratory analysis of immune status after six years, and found that baseline CD8+ T cell apoptosis was correlated with CD4 cell count gain beginning two years post enrollment. Patients with low levels of CD8+ T cell apoptosis at baseline (mean 2.2% ± 2.1 had significantly higher CD4 cell counts and more normalized CD4:CD8 ratios than patients with high CD8+ T cell apoptosis (mean CD4 cell counts 1,209 ± 164 vs 754 ± 320 cells/mm3; CD4:CD8 ratios 1.55 vs. 0.70, respectively. Conclusion We postulate that CD8+ T cell apoptosis may reflect inherent activation status, which continues in some patients even though viral replication is suppressed which influences the ability of CD4+ T cells to rebound. Levels of CD8+ T cell apoptosis may therefore be an independent predictor of immune status, which should be shown in a

  16. CD8 apoptosis may be a predictor of T cell number normalization after immune reconstitution in HIV

    Science.gov (United States)

    Lewis, Dorothy E; Gross, Kimber L; Diez, Martine M; Martinez, Maria L; Lukefahr, Helen N; Kozinetz, Claudia A; Arduino, Roberto C

    2007-01-01

    Background As part of the Houston Vanguard study, a subset of 10 patients randomized to receive IL-2 therapy were compared to 4 patients randomized to not receive IL-2, for markers of T cell activation and death during the first three cycles of IL-2. All patients were treated with combination antiretroviral therapy (ART) and were virally suppressed. The purpose of the study was to examine the role of CD8+ T cell death in responses to ART and IL-2 therapy. Methods Lymphocytes were examined at Day 0, 5 and 30 days during three cycles of IL-2 therapy. CD25, CD38, HLA-DR expression and annexin (cell death) were examined on CD4 and CD8 subpopulations. Follow up studies examined CD4 levels and CD4:CD8 reconstitution after 6 years using both univariant and multivariate analyses. Results Human lymphocytes responded to IL-2 therapy by upregulation of CD25 on CD4+ T cells, leading to an increase in CD4 cell counts. CD8+ T cells did not increase CD25 expression, but upregulated activation antigens (CD38 and DR) and had increased death. At baseline, 7 of the 14 patients had high CD8+ T cell apoptosis (mean 17.0% ± 6.0). We did an exploratory analysis of immune status after six years, and found that baseline CD8+ T cell apoptosis was correlated with CD4 cell count gain beginning two years post enrollment. Patients with low levels of CD8+ T cell apoptosis at baseline (mean 2.2% ± 2.1) had significantly higher CD4 cell counts and more normalized CD4:CD8 ratios than patients with high CD8+ T cell apoptosis (mean CD4 cell counts 1,209 ± 164 vs 754 ± 320 cells/mm3; CD4:CD8 ratios 1.55 vs. 0.70, respectively). Conclusion We postulate that CD8+ T cell apoptosis may reflect inherent activation status, which continues in some patients even though viral replication is suppressed which influences the ability of CD4+ T cells to rebound. Levels of CD8+ T cell apoptosis may therefore be an independent predictor of immune status, which should be shown in a prospective study. PMID:17263884

  17. Functional dichotomy between NKG2D and CD28-mediated co-stimulation in human CD8+ T cells.

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    Kamalakannan Rajasekaran

    2010-09-01

    Full Text Available Both CD28 and NKG2D can function as co-stimulatory receptors in human CD8+ T cells. However, their independent functional contributions in distinct CD8+ T cell subsets are not well understood. In this study, CD8+ T cells in human peripheral blood- and lung-derived lymphocytes were analyzed for CD28 and NKG2D expression and function. We found a higher level of CD28 expression in PBMC-derived naïve (CD45RA+CD27+ and memory (CD45RA-CD27+ CD8+ T cells (CD28Hi, while its expression was significantly lower in effector (CD45RA+CD27- CD8+ T cells (CD28Lo. Irrespective of the differences in the CD28 levels, NKG2D expression was comparable in all three CD8+ T cell subsets. CD28 and NKG2D expressions followed similar patterns in human lung-resident GILGFVFTL/HLA-A2-pentamer positive CD8+ T cells. Co-stimulation of CD28Lo effector T cells via NKG2D significantly increased IFN-γ and TNF-α levels. On the contrary, irrespective of its comparable levels, NKG2D-mediated co-stimulation failed to augment IFN-γ and TNF-α production in CD28Hi naïve/memory T cells. Additionally, CD28-mediated co-stimulation was obligatory for IL-2 generation and thereby its production was limited only to the CD28Hi naïve/memory subsets. MICA, a ligand for NKG2D was abundantly expressed in the tracheal epithelial cells, validating the use of NKG2D as the major co-stimulatory receptor by tissue-resident CD8+ effector T cells. Based on these findings, we conclude that NKG2D may provide an expanded level of co-stimulation to tissue-residing effector CD8+ T cells. Thus, incorporation of co-stimulation via NKG2D in addition to CD28 is essential to activate tumor or tissue-infiltrating effector CD8+ T cells. However, boosting a recall immune response via memory CD8+ T cells or vaccination to stimulate naïve CD8+ T cells would require CD28-mediated co-stimulation.

  18. Genome-Based In Silico Identification of New Mycobacterium tuberculosis Antigens Activating Polyfunctional CD8+ T Cells in Human Tuberculosis

    DEFF Research Database (Denmark)

    Tang, Sheila Tuyet; van Meijgaarden, Krista E.; Caccamo, Nadia

    2011-01-01

    8(+) T cell proliferation assays (CFSE dilution) in 41 M. tuberculosis-responsive donors identified 70 new M. tuberculosis epitopes. Using HLA/peptide tetramers for the 18 most prominently recognized HLA-A*0201-binding M. tuberculosis peptides, recognition by cured TB patients' CD8(+) T cells......-epitope/Ag repertoire for human CD8(+) T cells is much broader than hitherto suspected, and the newly identified M. tuberculosis Ags are recognized by (poly) functional CD8(+) T cells during control of infection. These results impact on TB-vaccine design and biomarker identification. The Journal of Immunology, 2011...

  19. CD8+ T Cells Mediate Female-Dominant IL-4 Production and Airway Inflammation in Allergic Asthma

    OpenAIRE

    Ito, Chihiro; Okuyama-Dobashi, Kaori; Miyasaka, Tomomitsu; Masuda, Chiaki; Sato, Miki; Kawano, Tasuku; Ohkawara, Yuichi; Kikuchi, Toshiaki; Takayanagi, Motoaki; Ohno, Isao

    2015-01-01

    The prevalence and severity of bronchial asthma are higher in females than in males after puberty. Although antigen-specific CD8+ T cells play an important role in the development of asthma through their suppressive effect on cytokine production, the contribution of CD8+ T cells to sex differences in asthmatic responses remains unclear. In the present study, we investigated the sex-specific effect of CD8+ T cells in the suppression of asthma using an ovalbumin mouse model of asthma. The numbe...

  20. Is a Human CD8 T-Cell Vaccine Possible, and if So, What Would It Take? CD8 T-Cell Vaccines: To B or Not to B?

    Science.gov (United States)

    Beura, Lalit K; Jameson, Stephen C; Masopust, David

    2017-12-18

    Although CD8 T-cell vaccines do not have the record of success of humoral-mediated vaccines, they do not receive the same degree of effort. Many diseases, including malaria, tuberculosis, and acquired immune deficiency syndrome (AIDS) have not yielded to vaccines, and intrinsic barriers may impede approaches limited solely to generating antibodies. Moreover, population growth and modernization are driving an increased pace of new emerging global health threats (human immunodeficiency virus [HIV] is a recent example), which will create unpredictable challenges for vaccinologists. Vaccine-elicited CD8 T cells may contribute to protective modalities, although their development will require a more thorough understanding of CD8 T-cell biology, practices for manufacturing and delivering CD8 T-cell-eliciting vectors that have acceptable safety profiles, and, ultimately, the political will and faith of those that make vaccine research funding decisions. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  1. Anaplasma phagocytophilum-Related Defects in CD8, NKT, and NK Lymphocyte Cytotoxicity

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    Diana G. Scorpio

    2018-04-01

    Full Text Available Human granulocytic anaplasmosis, caused by the tick-transmitted Anaplasma phagocytophilum, is not controlled by innate immunity, and induces a proinflammatory disease state with innate immune cell activation. In A. phagocytophilum murine infection models, hepatic injury occurs with production of IFNγ thought to be derived from NK, NKT cells, and CD8 T lymphocytes. Specific A. phagocytophilum ligands that drive inflammation and disease are not known, but suggest a clinical and pathophysiologic basis strikingly like macrophage activation syndrome (MAS and hemophagocytic syndrome (HPS. We studied in vivo responses of NK, NKT, and CD8 T lymphocytes from infected animals for correlates of lymphocyte-mediated cytotoxicity and examined in vitro interactions with A. phagocytophilum-loaded antigen-presenting cells (APCs. Murine splenocytes were examined and found deficient in cytotoxicity as determined by CD107a expression in vitro for specific CTL effector subsets as determined by flow cytometry. Moreover, A. phagocytophilum-loaded APCs did not lead to IFNγ production among CTLs in vitro. These findings support the concept of impaired cytotoxicity with A. phagocytophilum presentation by APCs that express MHC class I and that interact with innate and adaptive immune cells with or after infection. The findings strengthen the concept of an enhanced proinflammatory phenotype, such as MAS and HPS disease states as the basis of disease and severity with A. phagocytophilum infection, and perhaps by other obligate intracellular bacteria.

  2. Aging Converts Innate B1a Cells into Potent CD8+ T Cell Inducers.

    Science.gov (United States)

    Lee-Chang, Catalina; Bodogai, Monica; Moritoh, Kanako; Chen, Xin; Wersto, Robert; Sen, Ranjan; Young, Howard A; Croft, Michael; Ferrucci, Luigi; Biragyn, Arya

    2016-04-15

    B cell dysregulation in aging is thought to mostly occur in conventional B2 cells without affecting innate B1 cells. Elderly humans and mice also accumulate 4-1BBL(+)MHC class-I(Hi)CD86(Hi)B cells of unknown origin. In this article, we report that these cells, termed 4BL cells, are activated murine and possibly human B1a cells. The activation is mediated by aging human monocytes and murine peritoneal macrophages. They induce expression and activation of 4-1BBL and IFN-γR1 on B1a cells to subsequently upregulate membrane TNF-α and CD86. As a result, activated B1a/4BL cells induce expression of granzyme B in CD8(+)T cells by targeting TNFR2 via membrane TNF-α and providing costimulation with CD86. Thus, for the first time, to our knowledge, these results indicate that aging affects the function of B1a cells. Upon aging, these cells lose their tumor-supporting activity and become inducers of potentially antitumor and autoimmune CD8(+)T cells. Copyright © 2016 by The American Association of Immunologists, Inc.

  3. The CD8+ memory T-cell state of readiness is actively maintained and reversible

    Science.gov (United States)

    Allam, Atef; Conze, Dietrich B.; Giardino Torchia, Maria Letizia; Munitic, Ivana; Yagita, Hideo; Sowell, Ryan T.; Marzo, Amanda L.

    2009-01-01

    The ability of the adaptive immune system to respond rapidly and robustly upon repeated antigen exposure is known as immunologic memory, and it is thought that acquisition of memory T-cell function is an irreversible differentiation event. In this study, we report that many phenotypic and functional characteristics of antigen-specific CD8 memory T cells are lost when they are deprived of contact with dendritic cells. Under these circumstances, memory T cells reverted from G1 to the G0 cell-cycle state and responded to stimulation like naive T cells, as assessed by proliferation, dependence upon costimulation, and interferon-γ production, without losing cell surface markers associated with memory. The memory state was maintained by signaling via members of the tumor necrosis factor receptor superfamily, CD27 and 4-1BB. Foxo1, a transcription factor involved in T-cell quiescence, was reduced in memory cells, and stimulation of naive CD8 cells via CD27 caused Foxo1 to be phosphorylated and emigrate from the nucleus in a phosphatidylinositol-3 kinase–dependent manner. Consistent with these results, maintenance of G1 in vivo was compromised in antigen-specific memory T cells in vesicular stomatitis virus-infected CD27-deficient mice. Therefore, sustaining the functional phenotype of T memory cells requires active signaling and maintenance. PMID:19617575

  4. PD-1 Dependent Exhaustion of CD8+ T Cells Drives Chronic Malaria

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    Joshua M. Horne-Debets

    2013-12-01

    Full Text Available Malaria is a highly prevalent disease caused by infection by Plasmodium spp., which infect hepatocytes and erythrocytes. Blood-stage infections cause devastating symptoms and can persist for years. Antibodies and CD4+ T cells are thought to protect against blood-stage infections. However, there has been considerable difficulty in developing an efficacious malaria vaccine, highlighting our incomplete understanding of immunity against this disease. Here, we used an experimental rodent malaria model to show that PD-1 mediates up to a 95% reduction in numbers and functional capacity of parasite-specific CD8+ T cells. Furthermore, in contrast to widely held views, parasite-specific CD8+ T cells are required to control both acute and chronic blood-stage disease even when parasite-specific antibodies and CD4+ T cells are present. Our findings provide a molecular explanation for chronic malaria that will be relevant to future malaria-vaccine design and may need consideration when vaccine development for other infections is problematic.

  5. Strong homeostatic TCR signals induce formation of self-tolerant virtual memory CD8 T cells.

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    Drobek, Ales; Moudra, Alena; Mueller, Daniel; Huranova, Martina; Horkova, Veronika; Pribikova, Michaela; Ivanek, Robert; Oberle, Susanne; Zehn, Dietmar; McCoy, Kathy D; Draber, Peter; Stepanek, Ondrej

    2018-05-11

    Virtual memory T cells are foreign antigen-inexperienced T cells that have acquired memory-like phenotype and constitute 10-20% of all peripheral CD8 + T cells in mice. Their origin, biological roles, and relationship to naïve and foreign antigen-experienced memory T cells are incompletely understood. By analyzing T-cell receptor repertoires and using retrogenic monoclonal T-cell populations, we demonstrate that the virtual memory T-cell formation is a so far unappreciated cell fate decision checkpoint. We describe two molecular mechanisms driving the formation of virtual memory T cells. First, virtual memory T cells originate exclusively from strongly self-reactive T cells. Second, the stoichiometry of the CD8 interaction with Lck regulates the size of the virtual memory T-cell compartment via modulating the self-reactivity of individual T cells. Although virtual memory T cells descend from the highly self-reactive clones and acquire a partial memory program, they are not more potent in inducing experimental autoimmune diabetes than naïve T cells. These data underline the importance of the variable level of self-reactivity in polyclonal T cells for the generation of functional T-cell diversity. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.

  6. Cholesterol negatively regulates IL-9-producing CD8+ T cell differentiation and antitumor activity.

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    Ma, Xingzhe; Bi, Enguang; Huang, Chunjian; Lu, Yong; Xue, Gang; Guo, Xing; Wang, Aibo; Yang, Maojie; Qian, Jianfei; Dong, Chen; Yi, Qing

    2018-05-09

    CD8 + T cells can be polarized into IL-9-secreting (Tc9) cells. We previously showed that adoptive therapy using tumor-specific Tc9 cells generated stronger antitumor responses in mouse melanoma than classical Tc1 cells. To understand why Tc9 cells exert stronger antitumor responses, we used gene profiling to compare Tc9 and Tc1 cells. Tc9 cells expressed different levels of cholesterol synthesis and efflux genes and possessed significantly lower cholesterol content than Tc1 cells. Unique to Tc9, but not other CD8 + or CD4 + T cell subsets, manipulating cholesterol content in polarizing Tc9 cells significantly affected IL-9 expression and Tc9 differentiation and antitumor response in vivo. Mechanistic studies showed that IL-9 was indispensable for Tc9 cell persistence and antitumor effects, and cholesterol or its derivatives inhibited IL-9 expression by activating liver X receptors (LXRs), leading to LXR Sumoylation and reduced p65 binding to Il9 promoter. Our study identifies cholesterol as a critical regulator of Tc9 cell differentiation and function. © 2018 Ma et al.

  7. TCR Down-Regulation Controls Virus-Specific CD8+ T Cell Responses

    DEFF Research Database (Denmark)

    Bonefeld, Charlotte Menné; Haks, Mariëlle; Nielsen, Bodil

    2008-01-01

    The CD3gamma di-leucine-based motif plays a central role in TCR down-regulation. However, little is understood about the role of the CD3gamma di-leucine-based motif in physiological T cell responses. In this study, we show that the expansion in numbers of virus-specific CD8(+) T cells is impaired...... in mice with a mutated CD3gamma di-leucine-based motif. The CD3gamma mutation did not impair early TCR signaling, nor did it compromise recruitment or proliferation of virus-specific T cells, but it increased the apoptosis rate of the activated T cells by increasing down-regulation of the antiapoptotic...... molecule Bcl-2. This resulted in a 2-fold reduction in the clonal expansion of virus-specific CD8(+) T cells during the acute phase of vesicular stomatitis virus and lymphocytic choriomeningitis virus infections. These results identify an important role of CD3gamma-mediated TCR down-regulation in virus...

  8. Acquired transcriptional programming in functional and exhausted virus-specific CD8 T cells.

    Science.gov (United States)

    Youngblood, Ben; Wherry, E John; Ahmed, Rafi

    2012-01-01

    Failure to control viral infections such as HIV results in T-cell receptor (TCR) and inhibitory receptor driven exhaustion of antigen-specific T cells. Persistent signaling by these receptors during chronic viral infection sculpts the transcriptional regulatory programs of virus-specific T cells. The resulting gene expression profile is tailored to temper the potentially damaging effector functions of cytotoxic T cells and adapt them to an antigen-rich and inflammation-rich environment. Here we review recent studies investigating mechanisms of transcriptional regulation of effector, functional memory, and exhausted T-cell functions during acute versus chronic infections. Patterns of gene expression in virus-specific CD8 T cells are a result of a combination of pro and inhibitory signals from antigen presentation (TCR-mediated) and co-inhibitory receptor ligation (PD-1, 2B4). Further, memory-specific transcriptional regulation of 2B4 expression and signaling impose a self-limiting secondary effector response to a prolonged viral infection. Additionally, differentiation of functional memory CD8 T cells is coupled with acquisition of a repressive epigenetic program for PD-1 expression. However, chronic infection provides a signal that blocks the acquisition of these epigenetic modifications reinforcing the suppression of cytotoxic lymphocyte (CTL) functions in exhausted cells. Current findings suggest that the mechanism(s) that delineate functional memory versus exhaustion are coupled with acquisition of transcriptional programs at the effector stage of differentiation, reinforced by cessation or persistence of TCR signaling.

  9. Conventional CD4+ T cells present bacterial antigens to induce cytotoxic and memory CD8+ T cell responses.

    Science.gov (United States)

    Cruz-Adalia, Aránzazu; Ramirez-Santiago, Guillermo; Osuna-Pérez, Jesús; Torres-Torresano, Mónica; Zorita, Virgina; Martínez-Riaño, Ana; Boccasavia, Viola; Borroto, Aldo; Martínez Del Hoyo, Gloria; González-Granado, José María; Alarcón, Balbino; Sánchez-Madrid, Francisco; Veiga, Esteban

    2017-11-17

    Bacterial phagocytosis and antigen cross-presentation to activate CD8 + T cells are principal functions of professional antigen presenting cells. However, conventional CD4 + T cells also capture and kill bacteria from infected dendritic cells in a process termed transphagocytosis (also known as transinfection). Here, we show that transphagocytic T cells present bacterial antigens to naive CD8 + T cells, which proliferate and become cytotoxic in response. CD4 + T-cell-mediated antigen presentation also occurs in vivo in the course of infection, and induces the generation of central memory CD8 + T cells with low PD-1 expression. Moreover, transphagocytic CD4 + T cells induce protective anti-tumour immune responses by priming CD8 + T cells, highlighting the potential of CD4 + T cells as a tool for cancer immunotherapy.

  10. Prevalence of Oral Manifestations and Their Association with CD4/CD8 Ratio and HIV Viral Load in South India

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    Sharma Gaurav

    2011-01-01

    Full Text Available The objective of the present research was to determine the prevalence of oral manifestations in an HIV infected population from south India and evaluate their association with HIV viral load and CD4/CD8 ratio. Intraoral examination of 103 patients, whose CD4/CD8 ratio was available, were conducted. HIV viral loads were available for thirty patients only. The prevalence of oral manifestations was 80.6% (83/103. The most common oromucosal lesion was erythematous candidiasis (EC (38.8% followed by melanotic hyperpigmentation (35.9%. Patients having any oral manifestation had a mean CD4/CD8 ratio of 0.24. EC had positive predictive value of 85.0% for CD4/CD8 ratio 20,000 copies/mL (20,000 copies/mL.

  11. Progesterone impairs antigen-non-specific immune protection by CD8 T memory cells via interferon-γ gene hypermethylation.

    Science.gov (United States)

    Yao, Yushi; Li, Hui; Ding, Jie; Xia, Yixin; Wang, Lei

    2017-11-01

    Pregnant women and animals have increased susceptibility to a variety of intracellular pathogens including Listeria monocytogenes (LM), which has been associated with significantly increased level of sex hormones such as progesterone. CD8 T memory(Tm) cell-mediated antigen-non-specific IFN-γ responses are critically required in the host defense against LM. However, whether and how increased progesterone during pregnancy modulates CD8 Tm cell-mediated antigen-non-specific IFN-γ production and immune protection against LM remain poorly understood. Here we show in pregnant women that increased serum progesterone levels are associated with DNA hypermethylation of IFN-γ gene promoter region and decreased IFN-γ production in CD8 Tm cells upon antigen-non-specific stimulation ex vivo. Moreover, IFN-γ gene hypermethylation and significantly reduced IFN-γ production post LM infection in antigen-non-specific CD8 Tm cells are also observed in pregnant mice or progesterone treated non-pregnant female mice, which is a reversible phenotype following demethylation treatment. Importantly, antigen-non-specific CD8 Tm cells from progesterone treated mice have impaired anti-LM protection when adoptive transferred in either pregnant wild type mice or IFN-γ-deficient mice, and demethylation treatment rescues the adoptive protection of such CD8 Tm cells. These data demonstrate that increased progesterone impairs immune protective functions of antigen-non-specific CD8 Tm cells via inducing IFN-γ gene hypermethylation. Our findings thus provide insights into a new mechanism through which increased female sex hormone regulate CD8 Tm cell functions during pregnancy.

  12. Progesterone impairs antigen-non-specific immune protection by CD8 T memory cells via interferon-γ gene hypermethylation.

    Directory of Open Access Journals (Sweden)

    Yushi Yao

    2017-11-01

    Full Text Available Pregnant women and animals have increased susceptibility to a variety of intracellular pathogens including Listeria monocytogenes (LM, which has been associated with significantly increased level of sex hormones such as progesterone. CD8 T memory(Tm cell-mediated antigen-non-specific IFN-γ responses are critically required in the host defense against LM. However, whether and how increased progesterone during pregnancy modulates CD8 Tm cell-mediated antigen-non-specific IFN-γ production and immune protection against LM remain poorly understood. Here we show in pregnant women that increased serum progesterone levels are associated with DNA hypermethylation of IFN-γ gene promoter region and decreased IFN-γ production in CD8 Tm cells upon antigen-non-specific stimulation ex vivo. Moreover, IFN-γ gene hypermethylation and significantly reduced IFN-γ production post LM infection in antigen-non-specific CD8 Tm cells are also observed in pregnant mice or progesterone treated non-pregnant female mice, which is a reversible phenotype following demethylation treatment. Importantly, antigen-non-specific CD8 Tm cells from progesterone treated mice have impaired anti-LM protection when adoptive transferred in either pregnant wild type mice or IFN-γ-deficient mice, and demethylation treatment rescues the adoptive protection of such CD8 Tm cells. These data demonstrate that increased progesterone impairs immune protective functions of antigen-non-specific CD8 Tm cells via inducing IFN-γ gene hypermethylation. Our findings thus provide insights into a new mechanism through which increased female sex hormone regulate CD8 Tm cell functions during pregnancy.

  13. Analysis of CD57+ natural killer cells and CD8+ T lymphocytes in periapical granulomas and radicular cysts.

    Science.gov (United States)

    Silva, Luiz Arthur Barbosa da; Sá, Maria Alice Ramalho; Melo, Rafaela Albuquerque; Pereira, Joabe Dos Santos; Silveira, Éricka Janine Dantas da; Miguel, Márcia Cristina da Costa

    2017-12-18

    The aim of this study was to compare the number of CD57+ natural killer (NK) cells and CD8+ T lymphocytes between periapical granulomas (PGs) and radicular cysts (RCs). Twenty-fives cases of PGs and 25 of RCs were submitted to histological analysis and immunohistochemistry using anti-CD57 and anti-CD8 biomarkers. Positive cells were counted in 10 fields (400× magnification) and the median value was calculated for each case. Statistical tests were used to evaluate differences in the number of CD57+ NK cells and CD8+ T lymphocytes according to type of lesion, intensity of the infiltrate and thickness of the lining epithelium. The number of CD57+ NK cells and CD8+ T lymphocytes was higher in PGs than in RCs (p = 0.129 and p = 0.541, respectively). Comparison of the number of CD57+ NK cells in atrophic and hyperplastic epithelium revealed a larger number of cells in the atrophic epithelium (p = 0.042). A larger number of CD57+ NK cells and CD8+ T lymphocytes were observed in grade III infiltrates compared to grade I/II (p = 0.145 and p = 0.725, respectively). CD8+ T lymphocytes were more prevalent than CD57+ NK cells in most cases when PGs and RCs were analyzed separately or in combination (p < 0.0001). CD57+ NK cells and CD8+ T lymphocytes play a key role in antiviral defense and the presence of these cells supports evidence suggesting the participation of these microorganisms in the pathogenesis of PGs and RCs. The response mediated by CD8+ T lymphocytes was more frequent, indicating greater participation of the adaptive immunity in these chronic lesions.

  14. Analysis of CD57+ natural killer cells and CD8+ T lymphocytes in periapical granulomas and radicular cysts

    Directory of Open Access Journals (Sweden)

    Luiz Arthur Barbosa da Silva

    2017-12-01

    Full Text Available Abstract: The aim of this study was to compare the number of CD57+ natural killer (NK cells and CD8+ T lymphocytes between periapical granulomas (PGs and radicular cysts (RCs. Twenty-fives cases of PGs and 25 of RCs were submitted to histological analysis and immunohistochemistry using anti-CD57 and anti-CD8 biomarkers. Positive cells were counted in 10 fields (400× magnification and the median value was calculated for each case. Statistical tests were used to evaluate differences in the number of CD57+ NK cells and CD8+ T lymphocytes according to type of lesion, intensity of the infiltrate and thickness of the lining epithelium. The number of CD57+ NK cells and CD8+ T lymphocytes was higher in PGs than in RCs (p = 0.129 and p = 0.541, respectively. Comparison of the number of CD57+ NK cells in atrophic and hyperplastic epithelium revealed a larger number of cells in the atrophic epithelium (p = 0.042. A larger number of CD57+ NK cells and CD8+ T lymphocytes were observed in grade III infiltrates compared to grade I/II (p = 0.145 and p = 0.725, respectively. CD8+ T lymphocytes were more prevalent than CD57+ NK cells in most cases when PGs and RCs were analyzed separately or in combination (p < 0.0001. CD57+ NK cells and CD8+ T lymphocytes play a key role in antiviral defense and the presence of these cells supports evidence suggesting the participation of these microorganisms in the pathogenesis of PGs and RCs. The response mediated by CD8+ T lymphocytes was more frequent, indicating greater participation of the adaptive immunity in these chronic lesions.

  15. Oncolytic measles virus enhances antitumour responses of adoptive CD8+NKG2D+ cells in hepatocellular carcinoma treatment.

    Science.gov (United States)

    Chen, Aiping; Zhang, Yonghui; Meng, Gang; Jiang, Dengxu; Zhang, Hailin; Zheng, Meihong; Xia, Mao; Jiang, Aiqin; Wu, Junhua; Beltinger, Christian; Wei, Jiwu

    2017-07-12

    There is an urgent need for novel effective treatment for hepatocellular carcinoma (HCC). Oncolytic viruses (OVs) not only directly lyse malignant cells, but also induce potent antitumour immune responses. The potency and precise mechanisms of antitumour immune activation by attenuated measles virus remain unclear. In this study, we investigated the potency of the measles virus vaccine strain Edmonston (MV-Edm) in improving adoptive CD8 + NKG2D + cells for HCC treatment. We show that MV-Edm-infected HCC enhanced the antitumour activity of CD8 + NKG2D + cells, mediated by at least three distinct mechanisms. First, MV-Edm infection compelled HCC cells to express the specific NKG2D ligands MICA/B, which may contribute to the activation of CD8 + NKG2D + cells. Second, MV-Edm-infected HCC cells stimulated CD8 + NKG2D + cells to express high level of FasL resulting in enhanced induction of apoptosis. Third, intratumoural administration of MV-Edm enhanced infiltration of intravenously injected CD8 + NKG2D + cells. Moreover, we found that MV-Edm and adoptive CD8 + NKG2D + cells, either administered alone or combined, upregulated the immune suppressive enzyme indoleamine 2,3-dioxygenase 1 (IDO1) in HCC. Elimination of IDO1 by fludarabine enhanced antitumour responses. Taken together, our data provide a novel and clinically relevant strategy for treatment of HCC.

  16. Cytomegalovirus vector expressing RAE-1γ induces enhanced anti-tumor capacity of murine CD8+ T cells.

    Science.gov (United States)

    Tršan, Tihana; Vuković, Kristina; Filipović, Petra; Brizić, Ana Lesac; Lemmermann, Niels A W; Schober, Kilian; Busch, Dirk H; Britt, William J; Messerle, Martin; Krmpotić, Astrid; Jonjić, Stipan

    2017-08-01

    Designing CD8 + T-cell vaccines, which would provide protection against tumors is still considered a great challenge in immunotherapy. Here we show the robust potential of cytomegalovirus (CMV) vector expressing the NKG2D ligand RAE-1γ as CD8 + T cell-based vaccine against malignant tumors. Immunization with the CMV vector expressing RAE-1γ, delayed tumor growth or even provided complete protection against tumor challenge in both prophylactic and therapeutic settings. Moreover, a potent tumor control in mice vaccinated with this vector can be further enhanced by blocking the immune checkpoints TIGIT and PD-1. CMV vector expressing RAE-1γ potentiated expansion of KLRG1 + CD8 + T cells with enhanced effector properties. This vaccination was even more efficient in neonatal mice, resulting in the expansion and long-term maintenance of epitope-specific CD8 + T cells conferring robust resistance against tumor challenge. Our data show that immunomodulation of CD8 + T-cell responses promoted by herpesvirus expressing a ligand for NKG2D receptor can provide a powerful platform for the prevention and treatment of CD8 + T-cell sensitive tumors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. T CD3+CD8+ Lymphocytes Are More Susceptible for Apoptosis in the First Trimester of Normal Human Pregnancy

    Directory of Open Access Journals (Sweden)

    Dorota Darmochwal-Kolarz

    2014-01-01

    Full Text Available Aims. Normal human pregnancy is a complex process of many immunoregulatory mechanisms which protect fetus from the activation of the maternal immune system. The aim of the study was to investigate the apoptosis of lymphocytes in peripheral blood of normal pregnant patients and healthy nonpregnant women. Methods. Sixty pregnant women and 17 nonpregnant women were included in the study. Lymphocytes were isolated and labeled with anti-CD3, anti-CD4, and anti-CD8 monoclonal antibodies. Apoptosis was detected by CMXRos staining and analyzed using the flow cytometric method. Results. We found significantly higher apoptosis of total lymphocytes in peripheral blood of pregnant patients when compared to healthy nonpregnant women. The percentage of apoptotic T CD3+CD8+ cells in the first trimester was significantly higher when compared to the third trimester of normal pregnancy. The ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic lymphocytes was significantly lower in the first trimester when compared to other trimesters of pregnancy and to both of the phases of the menstrual cycle. Conclusions. The higher apoptosis of T CD3+CD8+ lymphocytes and the lower ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic cells in the first trimester of normal pregnancy may suggest a higher susceptibility of T CD3+CD8+ cells for apoptosis as a protective mechanism at the early stage of pregnancy.

  18. Mechanisms involved in the differential recovery of CD4 and CD8 T-lymphocytes after local irradiation in mice

    International Nuclear Information System (INIS)

    De Ruysscher, D; Waer, M.; Vandeputte, M.; Van der Schueren, E.

    1990-01-01

    The mechanisms involved in the differential recovery of CD4 (helper/inducer phenotype) and CD8 (Cytotoxic/suppressor phenotype) T-lymphocytes after fractionated local irradiation were investigated. In mice, a better recovery of CD4 cells than of CD8 cells was found, while the reverse has been described in humans. Differences in radiosensivitity between CD4 and CD8 mouse splenocytes could not be found. No sequestration of CD8 cells in irradiated tissues could be demonstrated. Irradiation of the thymus did not influence the observed immune changes. Altered thymic production of CD4 and CD8 cells could be excluded by intrathymic injection of FITC (fluorescein isothiocyanate). Hindlimb and tail irradiation did suggest that the differential recovery of CD4 and CD8 T-lymphocytes after local irradiation is determined by extrathymic factors in man and mice, and that the observed differences in immune recovery between man and mice are due to defective thymic function in the former and normal function in the latter. (author). 12 refs.; 5 figs.; 2 tabs

  19. Blimp-1–mediated CD4 T cell exhaustion causes CD8 T cell dysfunction during chronic toxoplasmosis

    Science.gov (United States)

    Cobb, Dustin A.; Bhadra, Rajarshi

    2016-01-01

    CD8, but not CD4, T cells are considered critical for control of chronic toxoplasmosis. Although CD8 exhaustion has been previously reported in Toxoplasma encephalitis (TE)–susceptible model, our current work demonstrates that CD4 not only become exhausted during chronic toxoplasmosis but this dysfunction is more pronounced than CD8 T cells. Exhausted CD4 population expressed elevated levels of multiple inhibitory receptors concomitant with the reduced functionality and up-regulation of Blimp-1, a transcription factor. Our data demonstrates for the first time that Blimp-1 is a critical regulator for CD4 T cell exhaustion especially in the CD4 central memory cell subset. Using a tamoxifen-dependent conditional Blimp-1 knockout mixed bone marrow chimera as well as an adoptive transfer approach, we show that CD4 T cell–intrinsic deletion of Blimp-1 reversed CD8 T cell dysfunction and resulted in improved pathogen control. To the best of our knowledge, this is a novel finding, which demonstrates the role of Blimp-1 as a critical regulator of CD4 dysfunction and links it to the CD8 T cell dysfunctionality observed in infected mice. The critical role of CD4-intrinsic Blimp-1 expression in mediating CD4 and CD8 T cell exhaustion may provide a rational basis for designing novel therapeutic approaches. PMID:27481131

  20. FOXP3+ regulatory T cells in cutaneous T-cell lymphomas: association with disease stage and survival

    DEFF Research Database (Denmark)

    Gjerdrum, L M; Woetmann, A; Odum, Niels

    2007-01-01

    FOXP3 is a unique marker for CD4+CD25+ regulatory T cells (Tregs). In solid tumours, high numbers of Tregs are associated with a poor prognosis. Knowledge about the implications of Tregs for the behaviour of haematological malignancies is limited. In this study, skin biopsies from 86 patients...... with mycosis fungoides (MF) and cutaneous T-cell lymphoma (CTCL) unspecified were analysed for the expression of FOXP3 on tumour cells and tumour-infiltrating Tregs. Labelling of above 10% of the neoplastic cells was seen in one case classified as an aggressive epidermotropic CD8+ cytotoxic CTCL....... In the remaining 85 cases, the atypical neoplastic infiltrate was either FOXP3 negative (n=80) or contained only very occasional weakly positive cells (n=5). By contrast, all biopsies showed varying numbers of strongly FOXP3+ tumour-infiltrating Tregs. MF with early or infiltrated plaques had significantly higher...

  1. CD8+ T Cells Complement Antibodies in Protecting against Yellow Fever Virus

    DEFF Research Database (Denmark)

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A

    2015-01-01

    The attenuated yellow fever (YF) vaccine (YF-17D) was developed in the 1930s, yet little is known about the protective mechanisms underlying its efficiency. In this study, we analyzed the relative contribution of cell-mediated and humoral immunity to the vaccine-induced protection in a murine model...... of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune...... response inside the infected CNS, we observed an accelerated T cell influx into the brain after intracerebral challenge of vaccinated mice, and this T cell recruitment correlated with improved virus control in the brain. Using mice deficient in B cells we found that, in the absence of Abs, YF vaccination...

  2. Selected microRNAs define cell fate determination of murine central memory CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Gonzalo Almanza

    2010-06-01

    Full Text Available During an immune response T cells enter memory fate determination, a program that divides them into two main populations: effector memory and central memory T cells. Since in many systems protection appears to be preferentially mediated by T cells of the central memory it is important to understand when and how fate determination takes place. To date, cell intrinsic molecular events that determine their differentiation remains unclear. MicroRNAs are a class of small, evolutionarily conserved RNA molecules that negatively regulate gene expression, causing translational repression and/or messenger RNA degradation. Here, using an in vitro system where activated CD8 T cells driven by IL-2 or IL-15 become either effector memory or central memory cells, we assessed the role of microRNAs in memory T cell fate determination. We found that fate determination to central memory T cells is under the balancing effects of a discrete number of microRNAs including miR-150, miR-155 and the let-7 family. Based on miR-150 a new target, KChIP.1 (K (+ channel interacting protein 1, was uncovered, which is specifically upregulated in developing central memory CD8 T cells. Our studies indicate that cell fate determination such as surface phenotype and self-renewal may be decided at the pre-effector stage on the basis of the balancing effects of a discrete number of microRNAs. These results may have implications for the development of T cell vaccines and T cell-based adoptive therapies.

  3. Cell-mediated immunity in recent-onset type 1 diabetic children

    African Journals Online (AJOL)

    EL-HAKIM

    diabetes (disease duration <6 months) who were compared to 10 healthy children. ... percentage (p<0.01) and significantly lower CD8+ CD25+ lymphocytes percentage (p<0.05) ..... cells CD8+ CD25+ T-reg cells act by direct cell to cell contact ...

  4. CXCL10/CXCR3-Dependent Mobilization of Herpes Simplex Virus-Specific CD8+ TEM and CD8+ TRM Cells within Infected Tissues Allows Efficient Protection against Recurrent Herpesvirus Infection and Disease.

    Science.gov (United States)

    Srivastava, Ruchi; Khan, Arif A; Chilukuri, Sravya; Syed, Sabrina A; Tran, Tien T; Furness, Julie; Bahraoui, Elmostafa; BenMohamed, Lbachir

    2017-07-15

    Herpes simplex virus 1 (HSV-1) establishes latency within the sensory neurons of the trigeminal ganglia (TG). HSV-specific memory CD8 + T cells play a critical role in preventing HSV-1 reactivation from TG and subsequent virus shedding in tears that trigger recurrent corneal herpetic disease. The CXC chemokine ligand 10 (CXCL10)/CXC chemokine receptor 3 (CXCR3) chemokine pathway promotes T cell immunity to many viral pathogens, but its importance in CD8 + T cell immunity to recurrent herpes has been poorly elucidated. In this study, we determined how the CXCL10/CXCR3 pathway affects TG- and cornea-resident CD8 + T cell responses to recurrent ocular herpesvirus infection and disease using a well-established murine model in which HSV-1 reactivation was induced from latently infected TG by UV-B light. Following UV-B-induced HSV-1 reactivation, a significant increase in both the number and function of HSV-specific CXCR3 + CD8 + T cells was detected in TG and corneas of protected C57BL/6 (B6) mice, but not in TG and corneas of nonprotected CXCL10 -/- or CXCR3 -/- deficient mice. This increase was associated with a significant reduction in both virus shedding and recurrent corneal herpetic disease. Furthermore, delivery of exogenous CXCL10 chemokine in TG of CXCL10 -/- mice, using the neurotropic adeno-associated virus type 8 (AAV8) vector, boosted the number and function of effector memory CD8 + T cells (T EM ) and tissue-resident memory CD8 + T cells (T RM ), but not of central memory CD8 + T cells (T CM ), locally within TG, and improved protection against recurrent herpesvirus infection and disease in CXCL10 -/- deficient mice. These findings demonstrate that the CXCL10/CXCR3 chemokine pathway is critical in shaping CD8 + T cell immunity, locally within latently infected tissues, which protects against recurrent herpesvirus infection and disease. IMPORTANCE We determined how the CXCL10/CXCR3 pathway affects CD8 + T cell responses to recurrent ocular herpesvirus

  5. Tissue-specific control of latent CMV reactivation by regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Maha Almanan

    2017-08-01

    Full Text Available Cytomegalovirus (CMV causes a persistent, lifelong infection. CMV persists in a latent state and undergoes intermittent subclinical viral reactivation that is quelled by ongoing T cell responses. While T cells are critical to maintain control of infection, the immunological factors that promote CMV persistence remain unclear. Here, we investigated the role of regulatory T cells (Treg in a mouse model of latent CMV infection using Foxp3-diphtheria toxin receptor (Foxp3-DTR mice. Eight months after infection, MCMV had established latency in the spleen, salivary gland, lung, and pancreas, which was accompanied by an increased frequency of Treg. Administration of diphtheria toxin (DT after establishment of latency efficiently depleted Treg and drove a significant increase in the numbers of functional MCMV-specific CD4+ and CD8+ T cells. Strikingly, Treg depletion decreased the number of animals with reactivatable latent MCMV in the spleen. Unexpectedly, in the same animals, ablation of Treg drove a significant increase in viral reactivation in the salivary gland that was accompanied with augmented local IL-10 production by Foxp3-CD4+T cells. Further, neutralization of IL-10 after Treg depletion significantly decreased viral load in the salivary gland. Combined, these data show that Treg have divergent control of MCMV infection depending upon the tissue. In the spleen, Treg antagonize CD8+ effector function and promote viral persistence while in the salivary gland Treg prevent IL-10 production and limit viral reactivation and replication. These data provide new insights into the organ-specific roles of Treg in controlling the reactivation of latent MCMV infection.

  6. Effector/memory CD8+ T cells synergize with co-stimulation competent macrophages to trigger autoimmune peripheral neuropathy.

    Science.gov (United States)

    Yang, Mu; Shi, Xiang Qun; Peyret, Corentin; Oladiran, Oladayo; Wu, Sonia; Chambon, Julien; Fournier, Sylvie; Zhang, Ji

    2018-04-05

    Autoimmune peripheral neuropathy (APN) such as Guillain Barre Syndrome (GBS) is a debilitating illness and sometimes life threatening. The molecular and cellular mechanisms remain elusive but exposure to environmental factors including viral/bacterial infection and injury is highly associated with disease incidence. We demonstrated previously that both male and female B7.2 (CD86) transgenic L31 and L31/CD4KO mice develop spontaneous APN. Here we further reveal that CD8 + T cells in these mice exhibit an effector/memory phenotype, which bears a resemblance to the CD8 + T cell response following persistent cytomegalovirus (CMV) infection in humans and mice, whilst CMV has been considered as one of the most relevant pathogens in APN development. These activated, peripheral myelin Ag specific CD8 + T cells are required for the disease initiation. While an injury to a peripheral nerve results in Wallerian degeneration in control littermates, the same injury accelerates the development of APN in other non-injured nerves of L31 mice which have a predisposed inflammatory background consisting of effector/memory CD8 + T (CD8 + T EM ) cells. However, CD8 + T EM cells alone are not sufficient. A certain threshold of B7.2 expression on nerve macrophages is an additional requisite. Our findings reveal that indeed, the synergism between CD8 + T EM cells and co-stimulation competent macrophages is crucial in inducing autoimmune-mediated peripheral neuropathy. The identification of decisive molecular/cellular players connecting environmental triggers and the occurrence of APN provides opportunities to prevent disease onset, reduce relapses and develop new therapeutic strategies. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  7. CD8+ T-Cells Count in Acute Myocardial Infarction in HIV Disease in a Predominantly Male Cohort

    Directory of Open Access Journals (Sweden)

    Oluwatosin A. Badejo

    2015-01-01

    Full Text Available Human Immunodeficiency Virus- (HIV- infected persons have a higher risk for acute myocardial infarction (AMI than HIV-uninfected persons. Earlier studies suggest that HIV viral load, CD4+ T-cell count, and antiretroviral therapy are associated with cardiovascular disease (CVD risk. Whether CD8+ T-cell count is associated with CVD risk is not clear. We investigated the association between CD8+ T-cell count and incident AMI in a cohort of 73,398 people (of which 97.3% were men enrolled in the U.S. Veterans Aging Cohort Study-Virtual Cohort (VACS-VC. Compared to uninfected people, HIV-infected people with high baseline CD8+ T-cell counts (>1065 cells/mm3 had increased AMI risk (adjusted HR=1.82, P<0.001, 95% CI: 1.46 to 2.28. There was evidence that the effect of CD8+ T-cell tertiles on AMI risk differed by CD4+ T-cell level: compared to uninfected people, HIV-infected people with CD4+ T-cell counts ≥200 cells/mm3 had increased AMI risk with high CD8+ T-cell count, while those with CD4+ T-cell counts <200 cells/mm3 had increased AMI risk with low CD8+ T-cell count. CD8+ T-cell counts may add additional AMI risk stratification information beyond that provided by CD4+ T-cell counts alone.

  8. Killing of targets by effector CD8 T cells in the mouse spleen follows the law of mass action

    Energy Technology Data Exchange (ETDEWEB)

    Ganusov, Vitaly V [Los Alamos National Laboratory

    2009-01-01

    In contrast with antibody-based vaccines, it has been difficult to measure the efficacy of T cell-based vaccines and to correlate the efficacy of CD8 T cell responses with protection again viral infections. In part, this difficulty is due to poor understanding of the in vivo efficacy of CD8 T cells produced by vaccination. Using a: recently developed experimental method of in vivo cytotoxicity we have investigated quantitative aspects of killing of peptide-pulsed targets by effector and memory CD8 T cells, specific to three epitopes of lymphocytic choriomeningitis virus (LCMV), in the mouse spleen. By analyzing data on killing of targets with varying number of epitope-specific effector and memory CD8 T cells, we find that killing of targets by effectors follows the law of mass-action, that is the death rate of peptide-pulsed targets is proportional to the frequency of CTLs in the spleen. In contrast, killing of targets by memory CD8 T cells does not follow the mass action law because the death rate of targets saturates at high frequencies of memory CD8 T cells. For both effector and memory cells, we also find little support for the killing term that includes the decrease of the death rate of targets with target cell density. Interestingly, our analysis suggests that at low CD8 T cell frequencies, memory CD8 T cells on the per capita basis are more efficient at killing peptide-pulsed targets than effectors, but at high frequencies, effectors are more efficient killers than memory T cells. Comparison of the estimated killing efficacy of effector T cells with the value that is predicted from theoretical physics and based on motility of T cells in lymphoid tissues, suggests that limiting step in the killing of peptide-pulsed targets is delivering the lethal hit and not finding the target. Our results thus form a basis for quantitative understanding of the process of killing of virus-infected cells by T cell responses in tissues and can be used to correlate the

  9. Priming of CD8 T Cells by Adenoviral Vectors Is Critically Dependent on B7 and Dendritic Cells but Only Partially Dependent on CD28 Ligation on CD8 T Cells

    DEFF Research Database (Denmark)

    Nielsen, Karen N; Steffensen, Maria A; Christensen, Jan P

    2014-01-01

    expression resulted in a delayed primary response, whereas memory CD8 T cells generated in CD28-deficient mice appeared almost normal in terms of both phenotype and effector cytokine profile, but they exhibited a significantly reduced proliferative capacity upon secondary challenge while retaining immediate...... in vivo effector capabilities: in vivo cytotoxicity and short-term in vivo protective capacity. Overall, our data point to an absolute requirement for professional APCs and the expression of the costimulatory molecules CD80/86 for efficient CD8 T cell priming by adenoviral vectors. Additionally, our......Adenoviral vectors have long been forerunners in the development of effective CD8 T cell-based vaccines; therefore, it is imperative that we understand the factors controlling the induction of robust and long-lasting transgene-specific immune responses by these vectors. In this study, we...

  10. Splenectomy alters distribution and turnover but not numbers or protective capacity of de novo generated memory CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Marie eKim

    2014-11-01

    Full Text Available The spleen is a highly compartmentalized lymphoid organ that allows for efficient antigen presentation and activation of immune responses. Additionally, the spleen itself functions to remove senescent red blood cells, filter bacteria, and sequester platelets. Splenectomy, commonly performed after blunt force trauma or splenomegaly, has been shown to increase risk of certain bacterial and parasitic infections years after removal of the spleen. Although previous studies report defects in memory B cells and IgM titers in splenectomized patients, the effect of splenectomy on CD8 T cell responses and memory CD8 T cell function remains ill defined. Using TCR-transgenic P14 cells, we demonstrate that homeostatic proliferation and representation of pathogen-specific memory CD8 T cells in the blood are enhanced in splenectomized compared to sham surgery mice. Surprisingly, despite the enhanced turnover, splenectomized mice displayed no changes in total memory CD8 T cell numbers nor impaired protection against lethal dose challenge with Listeria monocytogenes. Thus, our data suggest that memory CD8 T cell maintenance and function remain intact in the absence of the spleen.

  11. Experimental myositis inducible with transfer of dendritic cells presenting a skeletal muscle C protein-derived CD8 epitope peptide.

    Science.gov (United States)

    Okiyama, Naoko; Hasegawa, Hisanori; Oida, Takatoku; Hirata, Shinya; Yokozeki, Hiroo; Fujimoto, Manabu; Miyasaka, Nobuyuki; Kohsaka, Hitoshi

    2015-07-01

    It is suggested that polymyositis, an autoimmune inflammatory myopathy, is mediated by autoaggressive CD8 T cells. Skeletal muscle C protein is a self-antigen that induces C protein-induced myositis, a murine model of polymyositis. To establish a new murine model of myositis inducible with a single CD8 T-cell epitope peptide that derives from the C protein, three internet-based prediction systems were employed to identify 24 candidate peptides of the immunogenic fragment of the C protein and bind theoretically to major histocompatibility complex class I molecules of C57BL/6 (B6) mice. RMA-S cell assay revealed that a HILIYSDV peptide, amino acid position 399-406 of the C protein, had the highest affinity to the H2-K(b) molecules. Transfer of mature bone marrow-derived dendritic cells pulsed with HILIYSDV induced myositis in naive B6 mice. This myositis was suppressed by anti-CD8-depleting antibodies but not by anti-CD4-depleting antibodies. Because this myositis model is mediated by CD8 T cells independently of CD4 T cells, it should be a useful tool to investigate pathology of polymyositis and develop therapies targeting CD8 T cells. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Enumeration of CD4 and CD8 T-cells in HIV infection in Zimbabwe using a manual immunocytochemical method

    DEFF Research Database (Denmark)

    Gomo, E; Ndhlovu, P; Vennervald, B J

    2001-01-01

    OBJECTIVES: To enumerate CD4 and CD8 T-cells using the simple and cheap immuno-alkaline phosphatase (IA) method and to compare it with flow cytometry (FC); and to study the effects of duration of sample storage on the IA method results. DESIGN: Method comparison study. SETTING: Blair Research...... Laboratory, Harare, Zimbabwe. SUBJECTS: 41 HIV positive and 11 HIV negative men and women from Harare participating in HIV studies at Blair Research Laboratory, Zimbabwe. MAIN OUTCOME MEASURES: CD4 and CD8 T-cell counts by FC and the IA method. RESULTS: The IA method and FC were highly correlated for CD4...... counts (Spearman rs = 0.91), CD4 percentage (rs = 0.84), CD8 count (rs = 0.83), CD8 percentage (rs = 0.96) and CD4/CD8 ratio (rs = 0.89). However, CD4 cell counts and percentage measured by the IA method were (mean difference +/- SE) 133 +/- 24 cells/microL [corrected] and 6.7 +/- 1.1% higher than those...

  13. NOD1 cooperates with TLR2 to enhance T cell receptor-mediated activation in CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Blandine C Mercier

    Full Text Available Pattern recognition receptors (PRR, like Toll-like receptors (TLR and NOD-like receptors (NLR, are involved in the detection of microbial infections and tissue damage by cells of the innate immune system. Recently, we and others have demonstrated that TLR2 can additionally function as a costimulatory receptor on CD8 T cells. Here, we establish that the intracytosolic receptor NOD1 is expressed and functional in CD8 T cells. We show that C12-iEDAP, a synthetic ligand for NOD1, has a direct impact on both murine and human CD8 T cells, increasing proliferation and effector functions of cells activated via their T cell receptor (TCR. This effect is dependent on the adaptor molecule RIP2 and is associated with an increased activation of the NF-κB, JNK and p38 signaling pathways. Furthermore, we demonstrate that NOD1 stimulation can cooperate with TLR2 engagement on CD8 T cells to enhance TCR-mediated activation. Altogether our results indicate that NOD1 might function as an alternative costimulatory receptor in CD8 T cells. Our study provides new insights into the function of NLR in T cells and extends to NOD1 the recent concept that PRR stimulation can directly control T cell functions.

  14. Multiscale Modeling of the Early CD8 T-Cell Immune Response in Lymph Nodes: An Integrative Study

    Directory of Open Access Journals (Sweden)

    Sotiris A. Prokopiou

    2014-09-01

    Full Text Available CD8 T-cells are critical  in controlling infection by intracellular  pathogens. Upon encountering antigen presenting cells, T-cell receptor activation promotes the differentiation of naïve CD8 T-cells into strongly proliferating  activated and effector stages. We propose a 2D-multiscale computational model to study the maturation of CD8 T-cells in a lymph node controlled by their molecular profile. A novel molecular pathway is presented and converted into an ordinary differential  equation model, coupled with a cellular Potts model to describe cell-cell interactions. Key molecular  players such as activated IL2 receptor and Tbet levels  control the differentiation  from naïve into activated and effector stages, respectively,  while caspases and Fas-Fas ligand interactions control cell apoptosis.  Coupling  this molecular model to the cellular scale successfully  reproduces  qualitatively the evolution of total CD8 T-cell counts observed in mice lymph node, between Day 3 and 5.5 post-infection. Furthermore, this model allows us to make testable predictions  of the evolution of the different CD8 T-cell stages.

  15. Radiosensitivity of CD4 and CD8 positive human T lymphocytes by an in vitro colony formation assay

    International Nuclear Information System (INIS)

    Nakamura, Nori; Kusunoki, Yoichiro; Akiyama, Mitoshi.

    1989-12-01

    The recent development of an in vitro lymphocyte colony assay provides a new opportunity to examine possible variations in human radiosensitivity using peripheral blood lymphocytes (PBL) in place of the hitherto used skin fibroblast assay. Our recent study showed that most of the colonies consisted of lymphocytes bearing CD4 or CD8 antigens. Since the fraction of CD4 + and CD8 + cells in PBL differs among individuals, it was suspected that individual radiosensitivity might be biased by the different subset frequencies if the dose-survival curves of the CD4 + and CD8 + cells differed. In the present study, CD4 + lymphocytes (helper/inducer T cells) and CD8 + lymphocytes (suppressor/cytotoxic T cells) were isolated from PBL and their dose-survival curves were determined. The results showed that the D 10 (the dose required to reduce the surviving fraction to 10 %) was quite similar for these two types of cells (3.13 ± 0.10 Gy [mean ±SD] for CD4 + , 3.34 ± 0.50 Gy for CD8 + and 3.07 ± 0.05 Gy for the unsorted cells), supporting the use of a whole PBL population for screening of individuals with altered radiosensitivity. (author)

  16. Engagement of NKG2D on bystander memory CD8 T cells promotes increased immunopathology following Leishmania major infection.

    Directory of Open Access Journals (Sweden)

    Erika J Crosby

    2014-02-01

    Full Text Available One of the hallmarks of adaptive immunity is the development of a long-term pathogen specific memory response. While persistent memory T cells certainly impact the immune response during a secondary challenge, their role in unrelated infections is less clear. To address this issue, we utilized lymphocytic choriomeningitis virus (LCMV and Listeria monocytogenes immune mice to investigate whether bystander memory T cells influence Leishmania major infection. Despite similar parasite burdens, LCMV and Listeria immune mice exhibited a significant increase in leishmanial lesion size compared to mice infected with L. major alone. This increased lesion size was due to a severe inflammatory response, consisting not only of monocytes and neutrophils, but also significantly more CD8 T cells. Many of the CD8 T cells were LCMV specific and expressed gzmB and NKG2D, but unexpectedly expressed very little IFN-γ. Moreover, if CD8 T cells were depleted in LCMV immune mice prior to challenge with L. major, the increase in lesion size was lost. Strikingly, treating with NKG2D blocking antibodies abrogated the increased immunopathology observed in LCMV immune mice, showing that NKG2D engagement on LCMV specific memory CD8 T cells was required for the observed phenotype. These results indicate that bystander memory CD8 T cells can participate in an unrelated immune response and induce immunopathology through an NKG2D dependent mechanism without providing increased protection.

  17. Prediction of CD8+ Epitopes in Leishmania braziliensis Proteins Using EPIBOT: In Silico Search and In Vivo Validation.

    Directory of Open Access Journals (Sweden)

    Angelo Duarte

    Full Text Available Leishmaniasis is caused by intracellular Leishmania parasites that induce a T-cell mediated response associated with recognition of CD4+ and CD8+ T cell Line 1Lineepitopes. Identification of CD8+ antigenic determinants is crucial for vaccine and therapy development. Herein, we developed an open-source software dedicated to search and compile data obtained from currently available on line prediction algorithms.We developed a two-phase algorithm and implemented in an open source software called EPIBOT, that consolidates the results obtained with single prediction algorithms, generating a final output in which epitopes are ranked. EPIBOT was initially trained using a set of 831 known epitopes from 397 proteins from IEDB. We then screened 63 Leishmania braziliensis vaccine candidates with the EPIBOT trained tool to search for CD8+ T cell epitopes. A proof-of-concept experiment was conducted with the top eight CD8+ epitopes, elected by EPIBOT. To do this, the elected peptides were synthesized and validated for their in vivo cytotoxicity. Among the tested epitopes, three were able to induce lysis of pulsed-target cells.Our results show that EPIBOT can successfully search across existing prediction tools, generating a compiled list of candidate CD8+ epitopes. This software is fast and a simple search engine that can be customized to search over different MHC alleles or HLA haplotypes.

  18. In Situ Detection of Regulatory T Cells in Human Genital Herpes Simplex Virus Type 2 (HSV-2) Reactivation and Their Influence on Spontaneous HSV-2 Reactivation.

    Science.gov (United States)

    Milman, Neta; Zhu, Jia; Johnston, Christine; Cheng, Anqi; Magaret, Amalia; Koelle, David M; Huang, Meei-Li; Jin, Lei; Klock, Alexis; Layton, Erik D; Corey, Lawrence

    2016-07-01

    Herpes simplex virus type 2 (HSV-2) reactivation is accompanied by a sustained influx of CD4(+) and CD8(+) T cells that persist in genital tissue for extended periods. While CD4(+) T cells have long been recognized as being present in herpetic ulcerations, their role in subclinical reactivation and persistence is less well known, especially the role of CD4(+) regulatory T cells (Tregs). We characterized the Treg (CD4(+)Foxp3(+)) population during human HSV-2 reactivation in situ in sequential genital skin biopsy specimens obtained from HSV-2-seropositive subjects at the time of lesion onset up to 8 weeks after healing. High numbers of Tregs infiltrated to the site of viral reactivation and persisted in proximity to conventional CD4(+) T cells (Tconvs) and CD8(+) T cells. Treg density peaked during the lesion stage of the reactivation. The number of Tregs from all time points (lesion, healed, 2 weeks after healing, 4 weeks after healing, and 8 weeks after healing) was significantly higher than in control biopsy specimens from unaffected skin. There was a direct correlation between HSV-2 titer and Treg density. The association of a high Treg to Tconv ratio with high viral shedding suggests that the balance between regulatory and effector T cells influences human HSV-2 disease. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  19. Recent Advances in Targeting CD8 T-Cell Immunity for More Effective Cancer Immunotherapy

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    Aurélie Durgeau

    2018-01-01

    Full Text Available Recent advances in cancer treatment have emerged from new immunotherapies targeting T-cell inhibitory receptors, including cytotoxic T-lymphocyte associated antigen (CTLA-4 and programmed cell death (PD-1. In this context, anti-CTLA-4 and anti-PD-1 monoclonal antibodies have demonstrated survival benefits in numerous cancers, including melanoma and non-small-cell lung carcinoma. PD-1-expressing CD8+ T lymphocytes appear to play a major role in the response to these immune checkpoint inhibitors (ICI. Cytotoxic T lymphocytes (CTL eliminate malignant cells through recognition by the T-cell receptor (TCR of specific antigenic peptides presented on the surface of cancer cells by major histocompatibility complex class I/beta-2-microglobulin complexes, and through killing of target cells, mainly by releasing the content of secretory lysosomes containing perforin and granzyme B. T-cell adhesion molecules and, in particular, lymphocyte-function-associated antigen-1 and CD103 integrins, and their cognate ligands, respectively, intercellular adhesion molecule 1 and E-cadherin, on target cells, are involved in strengthening the interaction between CTL and tumor cells. Tumor-specific CTL have been isolated from tumor-infiltrating lymphocytes and peripheral blood lymphocytes (PBL of patients with varied cancers. TCRβ-chain gene usage indicated that CTL identified in vitro selectively expanded in vivo at the tumor site compared to autologous PBL. Moreover, functional studies indicated that these CTL mediate human leukocyte antigen class I-restricted cytotoxic activity toward autologous tumor cells. Several of them recognize truly tumor-specific antigens encoded by mutated genes, also known as neoantigens, which likely play a key role in antitumor CD8 T-cell immunity. Accordingly, it has been shown that the presence of T lymphocytes directed toward tumor neoantigens is associated with patient response to immunotherapies, including ICI, adoptive cell transfer

  20. Tissue-Resident Memory CD8+ T Cells: From Phenotype to Function

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    David J. Topham

    2018-03-01

    Full Text Available Tissue-resident memory CD8+ T cells are an important first line of defense from infection in peripheral non-lymphoid tissues, such as the mucosal tissues of the respiratory, digestive, and urogenital tracts. This memory T cell subset is established late during resolution of primary infection of those tissues, has a distinct genetic signature, and is often defined by the cell surface expression of CD69, CD103, CD49a, and CD44 in both mouse and human studies. The stimuli that program or imprint the unique gene expression and cell surface phenotypes on TRM are beginning to be defined, but much work remains to be done. It is not clear, for example, when and where the TRM precursors receive these signals, and there is evidence that supports imprinting in both the lymph node and the peripheral tissue sites. In most studies, expression of CD49a, CD103, and CD69 on T cells in the tissues appears relatively late in the response, suggesting there are precise environmental cues that are not present at the height of the acute response. CD49a and CD103 are not merely biomarkers of TRM, they confer substrate specificities for cell adhesion to collagen and E-cadherin, respectively. Yet, little attention has been paid to how expression affects the positioning of TRM in the peripheral tissues. CD103 and CD49a are not mutually exclusive, and not always co-expressed, although whether they can compensate for one another is unknown. In fact, they may define different subsets of TRM in certain tissues. For instance, while CD49a+CD8+ memory T cells can be found in almost all peripheral tissues, CD103 appears to be more restricted. In this review, we discuss the evidence for how these hallmarks of TRM affect positioning of T cells in peripheral sites, how CD49a and CD103 differ in expression and function, and why they are important for immune protection conferred by TRM in mucosal tissues such as the respiratory tract.

  1. Is an increase in CD4/CD8 T-cell ratio in lymph node fine needle aspiration helpful for diagnosing Hodgkin lymphoma? A study of 85 lymph node FNAs with increased CD4/CD8 ratio

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    Hernandez Osvaldo

    2005-01-01

    Full Text Available Abstract Background An elevated CD4/CD8 T-cell ratio on flow cytometry (FCM analysis has been reported in the literature to be associated with Hodgkin lymphoma (HL. The purpose of our study was to determine the diagnostic significance of an elevated CD4/CD8 ratio in lymph node fine needle aspiration (FNA specimens. Design Between 1996 and 2002, out of 837 lymph node FNAs submitted for flow cytometry analysis, 85 cases showed an elevated CD4/CD8 ratio, defined as greater than or equal to 4, without definitive evidence of a lymphoproliferative disorder. The cytologic diagnoses of these 85 cases were grouped into four categories: reactive, atypical, Hodgkin lymphoma (HL, and non-Hodgkin lymphoma (NHL. Histologic follow-up was available in 17/85 (20% of the cases. Results 5 of the 64 cases in which FCM and cytology did not reveal evidence of a lymphoproliferative disease had tissue follow-up because of persistent lymphadenopathy and high clinical suspicion. 3/5 (60% confirmed the diagnosis of reactive lymphadenopathy. The two remaining cases (40% were positive for lymphoma (1HL, 1NHL. 8/15 cases called atypical on cytology had histologic follow-up. 7/8 (87.5% cases were positive for lymphoma (3HL, 4NHL. 3/4 cases called HL on cytology had tissue follow-up and all 3 (100% confirmed the diagnosis of HL. One case diagnosed as NHL on cytology was found to be a diffuse large B-cell lymphoma. In summary, out of 17 cases with histologic follow-up 4/17 (24% were reactive with CD4/CD8 T-cell ratio of 4.1–29, 7/17 (41% were HLs with CD4/CD8 T-cell ratio of 5.3 – 11, and 6/17 (35% were NHLs with CD4/CD8 T-cell ratio of 4.2 – 14. Conclusion An elevated CD4/CD8 ratio on FCM is a nonspecific finding which may be seen in both reactive and lymphoproliferative disorders. The cytomorphologic features of the smear are more relevant than the sole flow cytometric finding of an elevated CD4/CD8 ratio.

  2. Increased level of both CD4+FOXP3+ regulatory T cells and CD14+HLA-DR⁻/low myeloid-derived suppressor cells and decreased level of dendritic cells in patients with multiple myeloma

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    Brimnes, Marie Klinge; Vangsted, Annette Juul; Meldgaard Knudsen, Lene

    2010-01-01

    +FOXP3+ Treg cells was increased in patients at diagnosis and not in patients in remission or with MGUS. Also, Treg cells from patients with MM were functionally intact as they were able to inhibit proliferation of both CD4 and CD8 T cells. Finally, we observed an increase in the proportion of CD14+HLA-DR...... as a consequence of the disease....

  3. SA-4-1BBL costimulation inhibits conversion of conventional CD4+ T cells into CD4+ FoxP3+ T regulatory cells by production of IFN-γ.

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    Shravan Madireddi

    Full Text Available Tumors convert conventional CD4(+ T cells into induced CD4(+CD25(+FoxP3(+ T regulatory (iTreg cells that serve as an effective means of immune evasion. Therefore, the blockade of conventional CD4(+ T cell conversion into iTreg cells represents an attractive target for improving the efficacy of various immunotherapeutic approaches. Using a novel form of 4-1BBL molecule, SA-4-1BBL, we previously demonstrated that costimulation via 4-1BB receptor renders both CD4(+and CD8(+ T effector (Teff cells refractory to inhibition by Treg cells and increased intratumoral Teff/Treg cell ratio that correlated with therapeutic efficacy in various preclinical tumor models. Building on these studies, we herein show for the first time, to our knowledge, that signaling through 4-1BB inhibits antigen- and TGF-β-driven conversion of naïve CD4(+FoxP3(- T cells into iTreg cells via stimulation of IFN-γ production by CD4(+FoxP3(- T cells. Importantly, treatment with SA-4-1BBL blocked the conversion of CD4(+FoxP3(- T cells into Treg cells by EG.7 tumors. Taken together with our previous studies, these results show that 4-1BB signaling negatively modulate Treg cells by two distinct mechanisms: i inhibiting the conversion of CD4(+FoxP3(- T cells into iTreg cells and ii endowing Teff cells refractory to inhibition by Treg cells. Given the dominant role of Treg cells in tumor immune evasion mechanisms, 4-1BB signaling represents an attractive target for favorably tipping the Teff:Treg balance toward Teff cells with important implications for cancer immunotherapy.

  4. Co-receptor choice by V alpha14i NKT cells is driven by Th-POK expression rather than avoidance of CD8-mediated negative selection.

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    Engel, Isaac; Hammond, Kirsten; Sullivan, Barbara A; He, Xi; Taniuchi, Ichiro; Kappes, Dietmar; Kronenberg, Mitchell

    2010-05-10

    Mouse natural killer T (NKT) cells with an invariant V alpha14-J alpha18 rearrangement (V alpha14 invariant [V alpha14i] NKT cells) are either CD4(+)CD8(-) or CD4(-)CD8(-). Because transgenic mice with forced CD8 expression in all T cells exhibited a profound NKT cell deficit, the absence of CD8 has been attributed to negative selection. We now present evidence that CD8 does not serve as a coreceptor for CD1d recognition and that the defect in development in CD8 transgene homozygous mice is the result of a reduction in secondary T cell receptor alpha rearrangements. Thymocytes from mice hemizygous for the CD8 transgene have a less severe rearrangement defect and have functional CD8(+) V alpha14i NKT cells. Furthermore, we demonstrate that the transcription factor Th, Poxviruses and Zinc finger, and Krüppel family (Th-POK) is expressed by V alpha14i NKT cells throughout their differentiation and is necessary both to silence CD8 expression and for the functional maturity of V alpha14i NKT cells. We therefore suggest that Th-POK expression is required for the normal development of V alpha14i NKT cells and that the absence of CD8 expression by these cells is a by-product of such expression, as opposed to the result of negative selection of CD8-expressing V alpha14i NKT cells.

  5. Vaginal type-II mucosa is an inductive site for primary CD8+ T-cell mucosal immunity

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    Wang, Yichuan; Sui, Yongjun; Kato, Shingo; Hogg, Alison E.; Steel, Jason C.; Morris, John C.; Berzofsky, Jay A.

    2014-01-01

    The structured lymphoid tissues are considered the only inductive sites where primary T cell immune responses occur. The naïve T cells in structured lymphoid tissues, once being primed by antigen -bearing dendritic cells, differentiate into memory T cells and traffic back to the mucosal sites through the bloodstream. Contrary to this belief, here we show that the vaginal type-II mucosa itself, despite lack of structured lymphoid tissues, can act as an inductive site during primary CD8+ T cell immune responses. We provide evidence that the vaginal mucosa supports both the local immune priming of naïve CD8+ T cells and the local expansion of antigen-specific CD8+ T cells, thereby demonstrating a different paradigm for primary mucosal T cell immune induction. PMID:25600442

  6. In vivo proliferation of naïve and memory influenza-specific CD8(+) T cells

    DEFF Research Database (Denmark)

    Flynn, K J; Riberdy, J M; Christensen, Jan Pravsgaard

    1999-01-01

    days. The greatly expanded population of CD8(+)NPP(+) memory T cells in the lymphoid tissue of secondarily challenged mice declines progressively in mean prevalence over the ensuing 100 days, despite the fact that at least some of these lymphocytes continue to cycle. The recall of cell......The virus-specific CD8(+) T cell response has been analyzed through the development, effector, and recovery phases of primary and secondary influenza pneumonia. Apparently, most, if not all, memory T cells expressing clonotypic receptors that bind a tetrameric complex of influenza nucleoprotein (NP......)(366-374) peptide+H-2D(b) (NPP) are induced to divide during the course of this localized respiratory infection. The replicative phase of the recall response ends about the time that virus can no longer be recovered from the lung, whereas some primary CD8(+)NPP(+) T cells may proliferate for a few more...

  7. Incomplete effector/memory differentiation of antigen-primed CD8+ T cells in gene gun DNA-vaccinated mice

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    Bartholdy, Christina; Stryhn, Anette; Hansen, Nils Jacob Vest

    2003-01-01

    DNA vaccination is an efficient way to induce CD8+ T cell memory, but it is still unclear to what extent such memory responses afford protection in vivo. To study this, we induced CD8+ memory responses directed towards defined viral epitopes, using DNA vaccines encoding immunodominant MHC class I......-restricted epitopes of lymphocytic choriomeningitis virus covalently linked to beta2-microglobulin. This vaccine construct primed for a stronger recall response than did a more conventional minigene construct. Despite this, vaccinated mice were only protected against systemic infection whereas protection against...... sites. Thus, our DNA vaccine induces a long-lived memory CD8+ T cell population that provides efficient protection against high-dose systemic infection. However, viral replication in solid non-lymphoid organs is not curtailed sufficiently fast to prevent significant virus-induced inflammation. Our...

  8. Estradiol-induced vaginal mucus inhibits antigen penetration and CD8(+) T cell priming in response to intravaginal immunization.

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    Seavey, Matthew M; Mosmann, Tim R

    2009-04-14

    Although vaginal immunization has been explored as a strategy to induce mucosal immunity in the female reproductive tract, this site displays unique immunological features that probably evolved to inhibit anti-paternal T cell responses after insemination to allow successful pregnancy. We previously demonstrated that estradiol, which induces an estrus-like state, prevented CD8(+) T cell priming during intravaginal immunization of mice. We now show that estradiol prevented antigen loading of vaginal antigen presenting cells (APCs) after intravaginal immunization. Histological examination confirmed that estradiol prevented penetration of peptide antigen into the vaginal wall. Removal of the estradiol-induced mucus barrier by mucinase partially restored antigen loading of vaginal APC and CD8(+) T cell proliferation in vivo. The estradiol-induced mucus barrier may thus prevent exposure to antigens delivered intravaginally, supplementing additional estradiol-dependent mechanism(s) that inhibit CD8(+) T cell priming after insemination or vaginal vaccination.

  9. Estradiol-induced vaginal mucus inhibits antigen penetration and CD8+ T cell priming in response to intravaginal immunization

    Science.gov (United States)

    Seavey, Matthew M.; Mosmann, Tim R.

    2010-01-01

    Although vaginal immunization has been explored as a strategy to induce mucosal immunity in the female reproductive tract, this site displays unique immunological features that probably evolved to inhibit anti-paternal T cell responses after insemination to allow successful pregnancy. We previously demonstrated that estradiol, which induces an estrus-like state, prevented CD8+ T cell priming during intravaginal immunization of mice. We now show that estradiol prevented antigen loading of vaginal antigen presenting cells (APC) after intravaginal immunization. Histological examination confirmed that estradiol prevented penetration of peptide antigen into the vaginal wall. Removal of the estradiol-induced mucus barrier by mucinase partially restored antigen loading of vaginal APC and CD8+ T cell proliferation in vivo. The estradiol-induced mucus barrier may thus prevent exposure to antigens delivered intravaginally, supplementing additional estradiol-dependent mechanism(s) that inhibit CD8+ T cell priming after insemination or vaginal vaccination. PMID:19428849

  10. Role of Therapeutic Plasma Exchange in Treatment of Tumefactive Multiple Sclerosis-Associated Low CD4 and CD8 Levels

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    Kristen Lew

    2016-08-01

    Full Text Available We report a 35-year-old healthy male who developed central nervous system inflammatory demyelinating disease consistent with tumefactive multiple sclerosis. About 2 weeks after onset of symptoms and prior to initiation of therapy, the patient had lymphopenia and low CD4 and CD8 levels. His lymphocyte count was 400 cells/µl (850–3,900 cells/µl, CD4 was 193 cells/µl (490–1,740 cells/µl and CD8 was 103 cells/µl (180–1,170 cells/µl. He was treated with intravenous methylprednisolone followed by therapeutic plasma exchange, the levels of CD4 and CD8 normalized, and ultimately, he recovered completely.

  11. A molecular threshold for effector CD8(+) T cell differentiation controlled by transcription factors Blimp-1 and T-bet.

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    Xin, Annie; Masson, Frederick; Liao, Yang; Preston, Simon; Guan, Tianxia; Gloury, Renee; Olshansky, Moshe; Lin, Jian-Xin; Li, Peng; Speed, Terence P; Smyth, Gordon K; Ernst, Matthias; Leonard, Warren J; Pellegrini, Marc; Kaech, Susan M; Nutt, Stephen L; Shi, Wei; Belz, Gabrielle T; Kallies, Axel

    2016-04-01

    T cell responses are guided by cytokines that induce transcriptional regulators, which ultimately control differentiation of effector and memory T cells. However, it is unknown how the activities of these molecular regulators are coordinated and integrated during the differentiation process. Using genetic approaches and transcriptional profiling of antigen-specific CD8(+) T cells, we reveal a common program of effector differentiation that is regulated by IL-2 and IL-12 signaling and the combined activities of the transcriptional regulators Blimp-1 and T-bet. The loss of both T-bet and Blimp-1 leads to abrogated cytotoxic function and ectopic IL-17 production in CD8(+) T cells. Overall, our data reveal two major overlapping pathways of effector differentiation governed by the availability of Blimp-1 and T-bet and suggest a model for cytokine-induced transcriptional changes that combine, quantitatively and qualitatively, to promote robust effector CD8(+) T cell differentiation.

  12. HLA-A*0201-restricted CD8+ cytotoxic T lymphocyte epitopes identified from herpes simplex virus glycoprotein D

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    Chentoufi, Aziz Alami; Zhang, Xiuli; Lamberth, Kasper

    2008-01-01

    Evidence obtained from both animal models and humans suggests that T cells specific for HSV-1 and HSV-2 glycoprotein D (gD) contribute to protective immunity against herpes infection. However, knowledge of gD-specific human T cell responses is limited to CD4+ T cell epitopes, with no CD8+ T cell ...... following ocular or genital infection with either HSV-1 or HSV-2. The functional gD CD8+ T cell epitopes described herein are potentially important components of clinical immunotherapeutic and immunoprophylactic herpes vaccines.......Evidence obtained from both animal models and humans suggests that T cells specific for HSV-1 and HSV-2 glycoprotein D (gD) contribute to protective immunity against herpes infection. However, knowledge of gD-specific human T cell responses is limited to CD4+ T cell epitopes, with no CD8+ T cell...

  13. Frequency of regulatory T cells determines the outcome of the T-cell-engaging antibody blinatumomab in patients with B-precursor ALL.

    Science.gov (United States)

    Duell, J; Dittrich, M; Bedke, T; Mueller, T; Eisele, F; Rosenwald, A; Rasche, L; Hartmann, E; Dandekar, T; Einsele, H; Topp, M S

    2017-10-01

    Blinatumomab can induce a complete haematological remission in patients in 46.6% with relapsed/refractory B-precursor acute lymphoblastic leukemia (r/r ALL) resulting in a survival benefit when compared with chemotherapy. Only bone marrow blast counts before therapy have shown a weak prediction of response. Here we investigated the role of regulatory T cells (Tregs), measured by CD4/CD25/FOXP3 expression, in predicting the outcome of immunotherapy with the CD19-directed bispecific T-cell engager construct blinatumomab. Blinatumomab responders (n=22) had an average of 4.82% Tregs (confidence interval (CI): 1.79-8.34%) in the peripheral blood, whereas non-responders (n=20) demonstrated 10.25% Tregs (CI: 3.36-65.9%). All other tested markers showed either no prediction value or an inferior prediction level including blast BM counts and the classical enzyme marker lactate dehydrogenase. With a cutoff of 8.525%, Treg enumeration can identify 100% of all blinatumomab responders and exclude 70% of the non-responders. The effect is facilitated by blinatumomab-activated Tregs, leading to interleukin-10 production, resulting in suppression of T-cell proliferation and reduced CD8-mediated lysis of ALL cells. Proliferation of patients' T cells can be restored by upfront removal of Tregs. Thus, enumeration of Treg identifies r/r ALL patients with a high response rate to blinatumomab. Therapeutic removal of Tregs may convert blinatumomab non-responders to responders.

  14. Increased numbers of CD4+ and CD8+ T cells in lesional skin of cats with allergic dermatitis.

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    Roosje, P J; van Kooten, P J; Thepen, T; Bihari, I C; Rutten, V P; Koeman, J P; Willemse, T

    1998-07-01

    The aim of this study was to characterize T cells in the skin of cats with an allergic dermatitis histologically compatible with atopic dermatitis, since T cells play an important role in the pathogenesis of atopic dermatitis in humans. We observed a significantly greater number of T cells in lesional skin of domestic short-haired cats with allergic dermatitis (n = 10; median age 5.8 years) than in the skin of healthy control animals (n = 10; median age 5.0 years). In the skin of the healthy control animals, one or two CD4+ cells and no CD8+ cells were found. A predominant increase of CD4+ T cells and a CD4+/CD8+ ratio (mean +/- SD: 3.9 +/- 2.0) was found in the lesional skin of 10 cats with allergic dermatitis. The CD4+/CD8+ cell ratio in the skin of healthy control animals could not be determined because of the absence of CD8+ cells. The CD4+/CD8+ cell ratio in the peripheral blood of 10 cats with allergic dermatitis (mean +/- SD: 1.9 +/- 0.4) did not differ significantly from that in 10 healthy control animals (2.2 +/- 0.4). The CD4+/CD8+ cell ratio and predominance of CD4+ T cells in the lesional skin of cats with allergic dermatitis is comparable to that found in atopic dermatitis in humans. In addition, the observed increase of CD4+ T cells in the nonlesional skin of cats with allergic dermatitis compared to the skin of healthy cats is similar to what is seen in humans. Cytokines produced by T cells and antigen-specific T cells are important mediators in the inflammatory cascade resulting in atopic dermatitis in humans. This study is a first step to investigate their role in feline allergic dermatitis.

  15. Collapse of Cytolytic Potential in SIV-Specific CD8+ T Cells Following Acute SIV Infection in Rhesus Macaques.

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    Emily R Roberts

    2016-12-01

    Full Text Available Poor maintenance of cytotoxic factor expression among HIV-specific CD8+ T cells, in part caused by dysregulated expression of the transcription factor T-bet, is associated with HIV disease progression. However, the precise evolution and context in which CD8+ T cell cytotoxic functions become dysregulated in HIV infection remain unclear. Using the rhesus macaque (RM SIV infection model, we evaluated the kinetics of SIV-specific CD8+ T cell cytolytic factor expression in peripheral blood, lymph node, spleen, and gut mucosa from early acute infection through chronic infection. We identified rapid acquisition of perforin and granzyme B expression in SIV-specific CD8+ T cells in blood, secondary lymphoid tissues and gut mucosa that collapsed rapidly during the transition to chronic infection. The evolution of this expression profile was linked to low expression of T-bet and occurred independent of epitope specificity, viral escape patterns and tissue origin. Importantly, during acute infection SIV-specific CD8+ T cells that maintained T-bet expression retained the ability to express granzyme B after stimulation, but this relationship was lost in chronic infection. Together, these data demonstrate the loss of cytolytic machinery in SIV-specific CD8+ T cells in blood and at tissue sites of viral reservoir and active replication during the transition from acute to chronic infection. This phenomenon occurs despite persistent high levels of viremia suggesting that an inability to maintain properly regulated cytotoxic T cell responses in all tissue sites enables HIV/SIV to avoid immune clearance, establish persistent viral reservoirs in lymphoid tissues and gut mucosa, and lead ultimately to immunopathogenesis and death.

  16. Presentation of an immunodominant immediate-early CD8+ T cell epitope resists human cytomegalovirus immunoevasion.

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    Stefanie Ameres

    Full Text Available Control of human cytomegalovirus (HCMV depends on CD8+ T cell responses that are shaped by an individual's repertoire of MHC molecules. MHC class I presentation is modulated by a set of HCMV-encoded proteins. Here we show that HCMV immunoevasins differentially impair T cell recognition of epitopes from the same viral antigen, immediate-early 1 (IE-1, that are presented by different MHC class I allotypes. In the presence of immunoevasins, HLA-A- and HLA-B-restricted T cell clones were ineffective, but HLA-C*0702-restricted T cell clones recognized and killed infected cells. Resistance of HLA-C*0702 to viral immunoevasins US2 and US11 was mediated by the alpha3 domain and C-terminal region of the HLA heavy chain. In healthy donors, HLA-C*0702-restricted T cells dominated the T cell response to IE-1. The same HLA-C allotype specifically protected infected cells from attack by NK cells that expressed a corresponding HLA-C-specific KIR. Thus, allotype-specific viral immunoevasion allows HCMV to escape control by NK cells and HLA-A- and HLA-B-restricted T cells, while the virus becomes selectively vulnerable to an immunodominant population of HLA-C-restricted T cells. Our work identifies a T cell population that may be of particular efficiency in HCMV-specific immunotherapy.

  17. The chromatin accessibility signature of human immune aging stems from CD8+ T cells.

    Science.gov (United States)

    Ucar, Duygu; Márquez, Eladio J; Chung, Cheng-Han; Marches, Radu; Rossi, Robert J; Uyar, Asli; Wu, Te-Chia; George, Joshy; Stitzel, Michael L; Palucka, A Karolina; Kuchel, George A; Banchereau, Jacques

    2017-10-02

    Aging is linked to deficiencies in immune responses and increased systemic inflammation. To unravel the regulatory programs behind these changes, we applied systems immunology approaches and profiled chromatin accessibility and the transcriptome in PBMCs and purified monocytes, B cells, and T cells. Analysis of samples from 77 young and elderly donors revealed a novel and robust aging signature in PBMCs, with simultaneous systematic chromatin closing at promoters and enhancers associated with T cell signaling and a potentially stochastic chromatin opening mostly found at quiescent and repressed sites. Combined analyses of chromatin accessibility and the transcriptome uncovered immune molecules activated/inactivated with aging and identified the silencing of the IL7R gene and the IL-7 signaling pathway genes as potential biomarkers. This signature is borne by memory CD8 + T cells, which exhibited an aging-related loss in binding of NF-κB and STAT factors. Thus, our study provides a unique and comprehensive approach to identifying candidate biomarkers and provides mechanistic insights into aging-associated immunodeficiency. © 2017 Ucar et al.

  18. Local Inflammatory Cues Regulate Differentiation and Persistence of CD8+ Tissue-Resident Memory T Cells

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    Tessa Bergsbaken

    2017-04-01

    Full Text Available Many pathogens initiate infection at mucosal surfaces, and tissue-resident memory T (Trm cells play an important role in protective immunity, yet the tissue-specific signals that regulate Trm differentiation are poorly defined. During Yersinia infection, CD8+ T cell recruitment to areas of inflammation within the intestine is required for differentiation of the CD103−CD69+ Trm subset. Intestinal proinflammatory microenvironments have elevated interferon (IFN-β and interleukin-12 (IL-12, which regulated Trm markers, including CD103. Type I interferon-receptor- or IL-12-receptor-deficient T cells functioned similarly to wild-type (WT cells during infection; however, the inability of T cells to respond to inflammation resulted in defective differentiation of CD103−CD69+ Trm cells and reduced Trm persistence. Intestinal macrophages were the main producers of IFN-β and IL-12 during infection, and deletion of CCR2+ IL-12-producing cells reduced the size of the CD103− Trm population. These data indicate that intestinal inflammation drives phenotypic diversity and abundance of Trm cells for optimal tissue-specific immunity.

  19. An unexpected antibody response to an engineered influenza virus modifies CD8+ T cell responses.

    Science.gov (United States)

    Thomas, Paul G; Brown, Scott A; Yue, Wen; So, Jenny; Webby, Richard J; Doherty, Peter C

    2006-02-21

    The ovalbumin(323-339) peptide that binds H2I-A(b) was engineered into the globular heads of hemagglutinin (H) molecules from serologically non-cross-reactive H1N1 and H3N2 influenza A viruses, the aim being to analyze recall CD4+ T cell responses in a virus-induced respiratory disease. Prime/challenge experiments with these H1ova and H3ova viruses in H2(b) mice gave the predicted, ovalbumin-specific CD4+ T cell response but showed an unexpectedly enhanced, early expansion of viral epitope-specific CD8+ T cells in spleen and a greatly diminished inflammatory process in the virus-infected respiratory tract. At the same time, the primary antibody response to the H3N2 challenge virus was significantly reduced, an effect that has been associated with preexisting neutralizing antibody in other experimental systems. Analysis of serum from the H1ova-primed mice showed low-level binding to H3ova but not to the wild-type H3N2 virus. Experiments with CD4+ T cell-depleted and Ig-/- mice indicated that this cross-reactive Ig is indeed responsible for the modified pathogenesis after respiratory challenge. Furthermore, the effect does not seem to be virus-dose related, although it does require infection. These findings suggest intriguing possibilities for vaccination and, at the same time, emphasize that engineered modifications in viruses may have unintended immunological consequences.

  20. CD8+ Tumor-Infiltrating T Cells Are Trapped in the Tumor-Dendritic Cell Network

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    Alexandre Boissonnas

    2013-01-01

    Full Text Available Chemotherapy enhances the antitumor adaptive immune T cell response, but the immunosuppressive tumor environment often dominates, resulting in cancer relapse. Antigen-presenting cells such as tumor-associated macrophages (TAMs and tumor dendritic cells (TuDCs are the main protagonists of tumor-infiltrating lymphocyte (TIL immuno-suppression. TAMs have been widely investigated and are associated with poor prognosis, but the immuno-suppressive activity of TuDCs is less well understood. We performed two-photon imaging of the tumor tissue to examine the spatiotemporal interactions between TILs and TuDCs after chemotherapy. In a strongly immuno-suppressive murine tumor model, cyclophosphamide-mediated chemotherapy transiently enhanced the antitumor activity of adoptively transferred ovalbumin-specific CD8+ T cell receptor transgenic T cells (OTI but barely affected TuDC compartment within the tumor. Time lapse imaging of living tumor tissue showed that TuDCs are organized as a mesh with dynamic interconnections. Once infiltrated into the tumor parenchyma, OTI T cells make antigen-specific and long-lasting contacts with TuDCs. Extensive analysis of TIL infiltration on histologic section revealed that after chemotherapy the majority of OTI T cells interact with TuDCs and that infiltration is restricted to TuDC-rich areas. We propose that the TuDC network exerts antigen-dependent unproductive retention that trap T cells and limit their antitumor effectiveness.

  1. IL-15 Harnesses Pro-inflammatory Function of TEMRA CD8 in Kidney-Transplant Recipients

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    Gaëlle Tilly

    2017-06-01

    Full Text Available The involvement of TEMRA CD8 is evident in a large array of immunological conditions ranging from auto- to allo-immunity. Nevertheless, the factors leading to their accumulation and activation remain ill-defined and, efficient therapeutics to control their inflammatory response is lacking. Here, we show that IL-15-stimulated TEMRA from kidney-transplant (KT recipients promote inflammation by inducing the expression of CX3CL1 by endothelial cells in an IFN-γ- and TNF-α-dependent manner. The responsiveness of TEMRA to IL-15 is not restricted to chronic stimulation, as TEMRA from healthy volunteers respond earlier and faster when compared to effector memory (EM. IL-15 induces antiapoptotic signals and promotes proliferation dependent of PI3K/Akt, MAPK, and ERK pathways. Without ex vivo stimulation, TEMRA cells are metabolically more active than naive and EM, as shown by their high ATP reservoir and a high expression of genes involved in glycolysis, glutaminolysis, and the Pentose Phosphate Pathway. Upon stimulation, TEMRA adapt their metabolism by sustaining an increased mitochondrial respiration and glycolysis. Finally, we show that the inhibition of glycolysis is highly effective in preventing endothelial inflammation induced by TEMRA from KT recipients. Together, our findings highlight the metabolic fitness that tightly regulates the immune function of TEMRA in physiological and pathogenic situations.

  2. Protective Role of Cross-Reactive CD8 T Cells Against Dengue Virus Infection

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    Annie Elong Ngono

    2016-11-01

    Full Text Available Infection with one of the four dengue virus serotypes (DENV1-4 presumably leads to lifelong immunity against the infecting serotype but not against heterotypic reinfection, resulting in a greater risk of developing Dengue Hemorrhagic Fever/Dengue Shock Syndrome (DHF/DSS during secondary infection. Both antibodies and T cell responses have been implicated in DHF/DSS pathogenesis. According to the T cell-based hypothesis termed “original antigenic sin,” secondary DENV infection is dominated by non-protective, cross-reactive T cells that elicit an aberrant immune response. The goal of our study was to compare the roles of serotype-specific and cross-reactive T cells in protection vs. pathogenesis during DENV infection in vivo. Specifically, we utilized IFN-α/βR−/− HLA*B0702 transgenic mice in the context of peptide vaccination with relevant human CD8 T cell epitopes. IFN-α/βR−/− HLA*B0702 transgenic mice were immunized with DENV serotype 2 (DENV2-specific epitopes or variants found in any of the other three serotypes (DENV1, DENV3 or DENV4, followed by challenge with DENV. Although cross-reactive T cell responses were lower than responses elicited by serotype-specific T cells, immunization with either serotype-specific or variant peptide epitopes enhanced viral clearance, demonstrating that both serotype-specific and cross-reactive T cells can contribute to protection in vivo against DENV infection.

  3. The role of Hsp0, CD-8 and IFN-γ in immunopathobiogenesis of periapical granuloma in dental caries

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    Risya Cilmiaty

    2014-03-01

    Full Text Available Background: The incidence of dental caries with periapical granulomas in Indonesia is quite high. However, the mechanism of the formation of periapical granulomas in dental caries caused by bacterial infection in immunopathobiogenesis cannot be explained completely. Thus, this explanation is necessary in order to be used as a basis for diagnostic, preventive and therapeutic measures. Purpose: This research was aimed to determine the role of Hsp60, CD-8 and IFN-γ in immunopatobiogenesis of periapical granuloma in dental caries. Methods: This research was an analytic observational study with cross sectional approach. Samples of this research were 36 teeth of patients with dental caries, consisting of 18 caries teeth with periapical granulomas and 18 caries teeth without periapical granulomas. The variables observed in this research were Hsp60, CD-8 and IFN-γ. Measurements were conducted by using immunohistochemical methods on periapical tissue. Results: The mean of Hsp60, CD-8 and IFN-γ in granuloma group was significantly higher than those in non granuloma group (p<0.05. The positive role of IFN-γ on the incidence of granulomas appeared to be more prominent. Conclusion: The study suggested that in immunopathobiogenesis of periapical granuloma in dental caries, Hsp60, CD-8 and IFN-γ played important roles, but the role of IFN-γ was found to be more prominent.Latar belakang: Angka kejadian gigi karies dengan granuloma periapikal di Indonesia cukup tinggi, Namun mekanisme terbentuknya granuloma periapikal pada gigi karies yang disebabkan oleh infeksi bakteri secara imunopatobiogenesis belum dapat dijelaskan secara tuntas. Adanya penjelasan ini diperlukan agar dapat digunakan sebagai dasar pengembangan diagnosis, langkah preventif dan terapinya. Tujuan: Penelitian ini bertujuan untuk mengetahui peran Hsp60, CD-8 dan IFN-γ dalam immunopatobiogenesis dari granuloma periapikal karies gigi. Metode: Penelitian ini merupakan penelitian observasional

  4. Interference with Intraepithelial TNF-α Signaling Inhibits CD8+ T-Cell-Mediated Lung Injury in Influenza Infection

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    Srikiatkhachorn, Anon; Chintapalli, Jyothi; Liu, Jun; Jamaluddin, Mohammad; Harrod, Kevin S.; Whitsett, Jeffrey A.; Enelow, Richard I.; Ramana, Chilakamarti V.

    2010-01-01

    CD8+ T-cell-mediated pulmonary immunopathology in respiratory virus infection is mediated in large part by antigen-specific TNF-α expression by antiviral effector T cells, which results in epithelial chemokine expression and inflammatory infiltration of the lung. To further define the signaling events leading to lung epithelial chemokine production in response to CD8+ T-cell antigen recognition, we expressed the adenoviral 14.7K protein, a putative inhibitor of TNF-α signaling, in the distal ...

  5. Comprehensive Analysis of CD8+-T-Cell Responses against Hepatitis C Virus Reveals Multiple Unpredicted Specificities

    OpenAIRE

    Lauer, Georg M.; Ouchi, Kei; Chung, Raymond T.; Nguyen, Tam N.; Day, Cheryl L.; Purkis, Deborah R.; Reiser, Markus; Kim, Arthur Y.; Lucas, Michaela; Klenerman, Paul; Walker, Bruce D.

    2002-01-01

    The hepatitis C virus (HCV)-specific CD8+-T-cell response is thought to play a critical role in HCV infection. Studies of these responses have largely relied on the analysis of a small number of previously described or predicted HCV epitopes, mostly restricted by HLA A2. In order to determine the actual breadth and magnitude of CD8+-T-cell responses in the context of diverse HLA class I alleles, we performed a comprehensive analysis of responses to all expressed HCV proteins. By using a panel...

  6. Expression and Significance of gp96 and Immune-related Gene CTLA-4, CD8 in Lung Cancer Tissues

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    Haiyan ZHENG

    2010-08-01

    Full Text Available Background and objective It has been proven that gp96 plays an important role in specific cytotoxic immune response which is involved in anti-tumor effect in the body. The aim of this study is to investigate the biological significance of heat shock protein gp96 and immune-related gene CTLA-4, CD8 expressions in lung cancer tissues of different progressive stages. Methods We used Envision immunohistochemistry method to detect the levels of expression of gp9