Tc17

Successful reconstitution of T lymphocytes after allogeneic haematopoietic stem cell transplantation (HSCT) is needed to establish the graft-versus-leukaemia effect and an effective anti-microbial defense, but the ratio between functionally different T-cell subsets needs to be balanced to avoid graft-versus-host disease (GVHD). IL-7 is essential for T-cell generation in the thymus and peripheral T-cell homeostasis. High IL-7 levels have been associated with impaired T-cell reconstitution, increased risk of acute GVHD and treatment-related mortality, but the underlying cellular mechanisms behind these associations have not been investigated previously...

A critical question facing the field of transplantation is how to control effector T cell (Teff) activation while preserving regulatory T cell (Treg) function. Standard calcineurin inhibitor-based strategies can partially control Teffs, but breakthrough activation still occurs, and these agents are antagonistic to Treg function. Conversely, mechanistic target of rapamycin (mTOR) inhibition with sirolimus is more Treg-compatible but is inadequate to fully control Teff activation. In contrast, blockade of OX40L signaling has the capacity to partially control Teff activation despite maintaining Treg function...

Background: TFF1 deficiency induces a mucosal pro-inflammatory phenotype that contributes to gastric tumorigenesis in mouse and human. Methods: We utilized the Tff1-KO mouse model to assess the impact of TFF1 loss on immune cells infiltration in the stomach. We used single cell suspension, flow cytometry, immunohistochemistry, and quantitative PCR (qPCR) assays. Results: The Tff1-KO gastric mucosa demonstrated high chronic inflammatory scores (score: 3-4) at age 2 months, which exacerbated at age 8 months (score: 4-6)...

Strongyloides stercoralis (Ss) infection is associated with diminished antigen - specific Th1- and Th17-associated responses and enhanced Th2-associated responses. IL-27 and IL-37 are 2 known anti-inflammatory cytokines that are highly expressed in Ss infection. We, therefore wanted to examine the role of IL-27 and IL-37 in regulating CD4(+) and CD8(+) T cell responses in Ss infection. To this end, we examined the frequency of Th1/Tc1, Th2/Tc2, Th9/Tc9, Th17/Tc17 and Th22/Tc22 cells in 15 Ss- infected individuals and 10 uninfected individuals, stimulated with parasite antigen following IL-27 or IL-37 neutralization...

Human natural killer receptor protein 1 (NKR-P1, CD161, gene klrb1) is a C-type lectin-like receptor of natural killer (NK) cells responsible for recognition of its cognate protein ligand lectin-like transcript 1 (LLT1). NKR-P1 is the single human orthologue of the prototypical rodent NKR-P1 receptors. Naturally, human NKR-P1 is expressed on the surface of NK cells, where it serves as inhibitory receptor; and on T and NKT cells functioning as co-stimulatory receptor promoting secretion of IFNγ. Most notably, it is expressed on Th17 and Tc17 lymphocytes where presumably promotes targeting into LLT1 expressing immunologically privileged niches...

The ability of different CD4(+) T cell subsets to help CD8(+) T-cell response is not fully understood. Here, we found using the murine system that Th17 cells induced by IL-1β, unlike Th1, were not effective helpers for antiviral CD8 responses as measured by IFNγ-producing cells or protection against virus infection. However, they skewed CD8 responses to a Tc17 phenotype. Thus, the apparent lack of help was actually immune deviation. This skewing depended on both IL-21 and IL-23. To overcome this effect, we inhibited Th17 induction by blocking TGF-β...

An HBsAg-HBIG therapeutic vaccine (Yeast-derived Immune Complexes, YIC) for chronic hepatitis B (CHB) patients has undergone a series of clinical trials. The HBeAg sero-conversion rate of YIC varied from 21.9% to 14% depending on the immunization protocols from 6 to 12 injections. To analyze the immunological mechanisms exerted by 6 injections of YIC, 44 CHB patients were separately immunized with YIC, alum as adjuvant control or normal saline as blank control, with add on of antiviral drug Adefovir in all groups...

BACKGROUND: An association between microscopic colitis (MC), i.e., lymphocytic colitis (LC) and collagenous colitis (CC), and inflammatory bowel diseases (IBD) has been noticed. A subset of MC cases may evolve into IBD, and IBD in remission may present as MC in a histologic pattern. Moreover, MC and IBD may coexist in different regions of the bowel. A link between MC and IBD in their pathogenesis is, therefore, suggested. Abnormal mucosal immunity is likely the key. METHODS: We reviewed 2324 MC cases in Calgary over 14 years and identified 20 cases evolved into IBD (IBD transformers)...

Type 2 diabetes mellitus (DM) is associated with the down modulation of Th1, Th2 and Th17 responses in latent Mycobacterium tuberculosis infection but the role of prediabetes (PDM) in this setting is not well understood. To examine the role of CD4+ and CD8+ T cell cytokines in latent tuberculosis (LTB) with coincident PDM, we studied the baseline, mycobacterial, control antigen and mitogen-stimulated T cell cytokine responses in LTB individuals with (LTB-PDM; n = 20) or without (LTB-NDM; n = 20) concomitant prediabetes...

Our understanding of persistence and plasticity of IL-17A+ memory T cells is clouded by conflicting results in models analyzing T helper 17 cells. We studied memory IL-17A+ CD8+ T-cell (Tc17) homeostasis, persistence and plasticity during fungal vaccine immunity. We report that vaccine-induced memory Tc17 cells persist with high fidelity to the type 17 phenotype. Tc17 cells persisted durably for a year as functional IL-17A+ memory cells without converting to IFNγ+ (Tc1) cells, although they produced multiple type I cytokines in the absence of residual vaccine antigen...

INTRODUCTION: HIV infection is characterized by a persistent immune activation associated to a compromised gut barrier immunity and alterations in the profile of the fecal flora linked with the progression of inflammatory symptoms. The effects of high concentration multistrain probiotic (Vivomixx®, Viale del Policlinico 155, Rome, Italy in EU; Visbiome®, Dupont, Madison, Wisconsin in USA) on several aspects of intestinal immunity in ART-experienced HIV-1 patients was evaluated. METHODS: A sub-study of a longitudinal pilot study was performed in HIV-1 patients who received the probiotic supplement twice a day for 6 months (T6)...

Immunometabolism is emerging as a critical determinant of cancer pathophysiology. In this study, we explored the contributions of macrophage-expressed lactate dehydrogenase-A (LDH-A) to tumor formation in a K-Ras murine model of lung carcinoma. Myeloid-specific deletion of LDH-A promoted accumulation of macrophages with a CD86(high) and MCP-1(high) M1-like phenotype that suppressed tumor growth. This phenotypic effect was accompanied by reduced VEGF expression and angiogenesis, diminished numbers of PD-L1(+) cancer cells, increased numbers of CD3(+) T cells, and activation status of CD8(+) T cells...

OBJECTIVE: In allergic asthma, regulatory T cell (Treg) number and function are decreased. Antigen-primed CD8(+) T cells play an indispensable role in the full development of airway inflammation and airway hyper-responsiveness (AHR) occurring in asthma. In this study, we investigated the relationship between subpopulations of CD8(+) T cells and CD39(+) Tregs. METHODS: Female C57BL/6 mice were used to develop the model of allergic asthma. Experimental mice were immunized with ovalbumin (OVA) by intra-peritoneal (i...

As the blockade of inhibitory surface-molecules such as CTLA-4 on T cells has led to recent advances in antitumor immune therapy, there is great interest in identifying novel mechanisms of action of CD8(+) T cells to evoke effective cytotoxic antitumor responses. Using in vitro and in vivo models, we investigated the molecular pathways underlying the CTLA-4-mediated differentiation of IL-17-producing CD8(+) T cells (Tc17 cells) that strongly impairs cytotoxicity. Our studies demonstrate that Tc17 cells lacking CTLA-4 signaling have limited production of STAT3-target gene products such as IL-17, IL-21, IL-23R and RORγt...

BACKGROUND: Poor graft function (PGF) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Nevertheless, whether abnormalities of T cell subsets in the bone marrow (BM) immune microenvironment, including Th17, Tc17, Th1, Tc1, Th2, Tc2 cells and regulatory T cells (Tregs), are involved in the pathogenesis of PGF remains unclear. METHODS: This prospective nested case-control study enrolled 20 patients with PGF, 40 matched patients with good graft function (GGF) after allo-HSCT, and 20 healthy donors (HD)...

Although a correlation between polymorphisms of NOD-like receptor family-pyrin domain containing 3 (NLRP3) and predisposition to type 1 diabetes (T1D) has been identified, the potential function and activation of the NLRP3 inflammasome in T1D have not been clarified. The present study shows that non-obese diabetic mice exhibited increased NLRP3, and pro-IL-1β gene expression in pancreatic lymph nodes (PLNs). Similar increases in gene expression of NLRP3, apoptosis associated speck like protein (ASC) and pro-IL-1β were induced by multiple low doses of streptozotocin (STZ) in C57BL/6 mice...

CD8(+) T cells that secrete proinflammatory cytokines play a central role in exacerbation of inflammation; however, a new subpopulation of CD8 regulatory T cells has recently been characterized. This study analyzes the prominent role of these different subpopulations in the development of graft-versus-host disease (GVHD). Samples from 8 healthy donors mobilized with Filgrastim® (G-CSF) and 18 patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) were evaluated by flow cytometry. Mobilization induced an increase in Tc1 (p < 0...

CD8(+) T cells that express retinoic acid-related orphan receptor (ROR)γt (TC17 cells) have been shown to promote procarcinogenic inflammation and contribute to a tolerogenic microenvironment in tumors. We investigated their phenotype and functional properties in relationship to the pathogenesis of human distal bile duct cancer (DBDC). DBDC patients had an elevated level of type 17 immune responses and the frequency of CD8(+)RORγt(+) T cells (TC17 cells) was increased in peripheral blood. The CD8(+)RORγt(+) T cells represented a highly activated subset and produced IL-17A in equal amount as CD4(+)RORγt(+) T cells (TH17 cells)...

BACKGROUND: Cytotoxic CD8+ T cells, as essential parts of the adaptive immune system, play pivotal roles in anti-tumor immune responses. It is well documented that cytokine expression profiles and activation status of these cells during anti-tumor immune responses affect the outcome of host-tumor interaction. OBJECTIVE: To investigate the percentages of CD8+ lymphocytes and their subsets in tumor draining lymph nodes of patients with bladder cancer. METHODS: Forty-five patients with bladder cancer, candidate for radical cystectomy, were recruited...

INTRODUCTION: Tc17 cells are interleukin (IL)-17-producing CD8(+) T cells and have been found to participate in the development of allergic asthma. Interleukin-23 is a cytokine that may be involved in modulating the IL-17 response via Th17 cells. This study aimed to investigate whether IL-23 also has immunomodulatory effects on Tc17 cells. MATERIAL AND METHODS: An allergic asthmatic mouse model was induced by sensitizing and challenging with ovalbumin (OVA). Anti-IL-23 antibody was administered intratracheally before challenge to the OVA-induced asthmatic mouse model...