Search results for " gamma-delta"
showing 10 items of 86 documents
γδ cells and tumor microenvironment: A helpful or a dangerous liason?
2017
Abstract γδ T cells are a subset of T lymphocytes that have been implicated in immunosurveillance against infections and tumors. γδ T cells are endowed with antitumor activities, and hence several γδ T cell-based small-scale clinical trials have been conducted either by in vivo activation by intravenous administration of aminobiphosphonates or by adoptive transfer of in vitro expanded γδ T cells. Although both these strategies have yielded promising results, there are a number of limitations associated with each of them which, if overcome may help to further improve efficacy. One of the most important limits is the possible polarization of tumor-infiltrating γδ T cells toward different γδ T…
T cells mediate autoantibody-induced cutaneous inflammation and blistering in epidermolysis bullosa acquisita
2016
AbstractT cells are key players in autoimmune diseases by supporting the production of autoantibodies. However, their contribution to the effector phase of antibody-mediated autoimmune dermatoses, i.e., tissue injury and inflammation of the skin, has not been investigated. In this paper, we demonstrate that T cells amplify the development of autoantibody-induced tissue injury in a prototypical, organ-specific autoimmune disease, namely epidermolysis bullosa acquisita (EBA) – characterized and caused by autoantibodies targeting type VII collagen. Specifically, we show that immune complex (IC)-induced inflammation depends on the presence of T cells – a process facilitated by T cell receptor (…
NKp46-expressing human gut-resident intraepithelial Vδ1 T cell subpopulation exhibits high antitumor activity against colorectal cancer
2019
γδ T cells account for a large fraction of human intestinal intraepithelial lymphocytes (IELs) endowed with potent anti-tumor activities. However, little is known about their origin, phenotype and clinical relevance in colorectal cancer (CRC). To determine γδ IEL gut-specificity, homing and functions, γδ T cells were purified from human healthy blood, lymph nodes, liver, skin, intestine either disease-free or affected by CRC or generated from thymic precursors. The constitutive expression of NKp46 specifically identifies a new subset of cytotoxic Vδ1 T cells representing the largest fraction of gut-resident IELs. The ontogeny and gut-tropism of NKp46pos/Vδ1 IELs depends both on distinctive …
Analysis of colon-infiltrating γδ T cells in chronic inflammatory bowel disease and in colitis-associated cancer
2019
Abstract Inflammatory bowel disease (IBD) remains a global health problem with a significant percentage of patients progressing to chronic inflammation and colitis-associated cancer (CAC). Whether or not γδ T cells contribute to initiation and maintenance of inflammation in IBD and in the development of CAC is not known. We have evaluated the frequency, phenotype, and functions of γδ T cells among tissue-infiltrating lymphocytes in healthy donors and IBD and CAC patients. Results show that Vδ1 T cells are the dominant γδ T-cell population in healthy tissue, whereas Vδ2 T significantly abound in chronic IBD. Vδ2 T cells produce more IFN-γ, TNF-α, and IL-17 than Vδ1 T cells in chronic inflame…
CD3ε Expression Defines Functionally Distinct Subsets of Vδ1 T Cells in Patients With Human Immunodeficiency Virus Infection
2018
Human γδ T cells expressing the Vδ1 T cell receptor (TCR) recognize self and microbial antigens and stress-inducible molecules in a major histocompatibility complex -unrestricted manner and are an important source of innate interleukin-17. Vδ1 T cells are expanded in the circulation and intestines of patients with human immunodeficiency virus (HIV) infection. In the present study, we show that patients with HIV have elevated frequencies, but not absolute numbers, of circulating Vδ1 T cells compared to control subjects. This increase was most striking in the patients with Candida albicans co-infection. Using flow cytometry and confocal microscopy, we identify two populations of Vδ1 T cells, …
Decrease in αβ/γδ T-cell ratio is accompanied by a reduction in high-fat diet-induced weight gain, insulin resistance, and inflammation.
2018
The implication of αβ and γδ T cells in obesity-associated inflammation and insulin resistance (IR) remains uncertain. Mice lacking γδ T cells show either no difference or a decrease in high-fat diet (HFD)-induced IR, whereas partial depletion in γδ T cells does not protect from HFD-induced IR. αβ T-cell deficiency leads to a decrease in white adipose tissue (WAT) inflammation and IR without weight change, but partial depletion of these cells has not been studied. We previously described a mouse model overexpressing peroxisome proliferator-activated receptor β (PPAR-β) specifically in T cells [transgenic (Tg) T-PPAR-β] that exhibits a partial depletion in αβ T cells and no change in γδ T-ce…
The actin remodeling protein cofilin is crucial for thymic αβ but not γδ T-cell development
2018
Cofilin is an essential actin remodeling protein promoting depolymerization and severing of actin filaments. To address the relevance of cofilin for the development and function of T cells in vivo, we generated knock-in mice in which T-cell–specific nonfunctional (nf) cofilin was expressed instead of wild-type (WT) cofilin. Nf cofilin mice lacked peripheral αβ T cells and showed a severe thymus atrophy. This was caused by an early developmental arrest of thymocytes at the double negative (DN) stage. Importantly, even though DN thymocytes expressed the TCRβ chain intracellularly, they completely lacked TCRβ surface expression. In contrast, nf cofilin mice possessed normal numbers of γδ T cel…
Chemotherapy accelerates immune-senescence and functional impairments of Vδ2pos T cells in elderly patients affected by liver metastatic colorectal c…
2019
Abstract Human (gamma delta) γδ T cells are unconventional innate-like lymphocytes displaying a broad array of anti-tumor activities with promising perspectives in cancer immunotherapy. In this context, Vδ2pos T cells represent the preferential target of several immunotherapy protocols against solid tumors. However, the impact of both aging and chemotherapy (CHT) on Vδ2pos T cells is still unknown. The present study evaluates with multi-parametric flow cytometry the frequencies, terminal differentiation, senescence and effector-functions of peripheral blood and tumor infiltrating Vδ2pos T cells purified from liver metastases (CLM) of patients affected by colorectal cancer (CRC) compared to …
Deciphering human γδ T cell response in cancer: Lessons from tumor‐infiltrating γδ T cells
2020
The finding that γδ T cells are present among tumor-infiltrating lymphocytes in humans suggests they participate in tumor immune surveillance, but their relevance is unclear because the relative abundance of tumor-infiltrating γδ T cells correlates with positive or negative, or even do not correlate with prognosis. This likely depends on the fact that tumor-infiltrating γδ T cells may play substantially different effector or regulatory functions, and correlation with patient's prognosis relies on distinct γδ T cell subsets in the context of the tumor. There is interest to exploit γδ T cells in tumor immunotherapy, but to make this approach successful there is urgent need to fully understand…
Γδ T Cell-Based Immunotherapy in Melanoma: State of the Art
2019
Metastatic melanoma is still associated with a poor prognosis, and there is increasing interest in immunotherapy alone or in combination with other adjuvant therapies. Γδ T lymphocytes play a pivot role in the immune response against cancer, but while γδ-based immunotherapy is already a clinical reality for several solid tumors, data on melanoma are still limited and fragmented. This systematic review presents preclinical and clinical evidence for a role of γδ T lymphocytes in immunotherapeutic strategies for advanced melanoma and discusses research state of the art and future perspectives. Current strategies focus on in vivo stimulation, and ex vivo adoptive therapy and vaccination; result…