Search results for "Lymphocyte"
showing 10 items of 2280 documents
Effect of isoprinosine on IL-2, IFN-γ and IL-4 production in vivo and in vitro
1991
The effects of an immunopotentiating drug, isoprinosine, on the splenocytes of BALB/c mice to produce cytokines were investigated. Isoprinosine enhanced IL-2 production, upregulating the expression of IL-2 receptor in vitro. It also significantly increased the IFN-gamma secretion and decreased the IL-4 production in vivo. The significance of these findings in terms of immune regulation is discussed.
Growth, interleukin-2 production, and responsiveness to IL-2 in T4- positive T Lymphocyte populations from malignant cutaneous T cell lymphoma (Sezar…
1984
Abstract Functional analysis and surface phenotyping using monoclonal antibodies have revealed that malignant T lymphocyte populations in the peripheral blood of patients with Sezary's syndrome resemble the T helper cell populations from normal individuals. In this article we have studied the effects of the immunosuppressive drug cyclosporine A (CsA) on growth, interleukin-2 (IL-2) production, and the induction of IL-2 responsiveness of peripheral blood monocytes (PBMs) from five patients with Sezary's syndrome in vitro, using the lectin phytohemagglutinin (PHA) and the phorbol ester phorbol myristate acetate (PMA) as stimuli. The following results were obtained: PHA-induced cell proliferat…
Inhibition of Delayed-Type Hypersensitivity by Cucurbitacin R through the Curbing of Lymphocyte Proliferation and Cytokine Expression by Means of Nuc…
2009
Cucurbitacin R is known to exhibit an anti-inflammatory effect in different experimental models of inflammation. In this article, we outline the effect of cucurbitacin R on T lymphocyte proliferation, cytokine production, and nuclear factor activation, as well as its influence on various experimental models of delayed-type hypersensitivity (DTH) in mice. Cucurbitacin R reduced the proliferation of phytohemagglutinin A-stimulated human T lymphocytes (IC(50), 18 microM), modifying the cell cycle, as well as the production of cytokines [interleukin (IL)-2, IL-4, IL-10, and especially interferon-gamma] and the induction of the principal cyclins implicated in the cell cycle (A(1), B(1), D(2), an…
Establishment of different T cell sublines using either interleukin 2 or interleukin 4 as growth factors
1990
Purified protein derivative reactive T cell lines were established under identical conditions with the exception that different lymphokines, namely interleukin (IL) 2 and IL 4 were employed as growth factors. IL 2 favored the development of T cell lines (LNC.2) which upon activation by concanavalin A (Con A) secreted predominantly lymphokines characteristic of TH1 cells. By contrast, T cell lines established with the aid of IL 4 as growth factor (LNC.4) produced mainly lymphokines representative of TH2 cells. Apart from their pattern of lymphokine secretion LNC.2 and LNC.4 T cells were found to differ in their proliferative response to lymphokines and Con A. LNC.2 T cells proliferated only …
Induction of regulatory Tr1 cells and inhibition of TH17 cells by IL-27
2011
Accumulating evidence indicates that IL-27, a member of the IL-12 family of cytokines, alleviates the severity of autoimmune diseases in both mice and men. The IL-27-induced activation of signal transducer and activator of transcription (Stat)1 and Stat3 promotes the generation of IL-10- producing type 1 regulatory T (Tr1) cells that inhibit effector T cells. In addition, IL-27 also suppresses the development of pathogenic IL-17-producing CD4(+) T cells (T(H)17) cells suggesting that pharmacological manipulations of IL-27 signaling pathway could be exploited therapeutically in regulating tissue inflammation. Here, we review how IL-27 controls inflammation through the regulation of Tr1 and T…
Functionally Active T Cell Receptor/CD3 Complexes Are Present at the Surface of Cloned Cytotoxic T Cells without Fluorescence-Immunological Detectabi…
1996
The cytotoxic T cell clone 10BK.1 is activated in response to the ovalbumin peptide OVA257-264 in a major histocompatibility complex class I-restricted manner. Following activation 10BK.1 cells proliferate, secrete lymphokines, and kill syn- and allogeneic target cells. Using immunofluorescence analysis we detected CD8, LFA-1, and ICAM-1 on the surface of 10BK.1 cells, but no CD3 or T cell receptor (TCR). In contrast, the proliferative response of 10BK.1 cells to antigen was efficiently blocked by soluble antibodies directed at CD3 epsilon or TCR alpha beta, but not by antibodies directed at TCR gamma delta. In addition, lysis of target cells was blocked by F(ab')2 fragments of antibodies d…
Concentration-Dependent Protection by Ethanol Extract ofPropolis against γ
2011
[EN] Radioprotection with natural products may be relevant to the mitigation of ionizing radiation-induced damage in mammalian systems; in this sense, propolis extracts have shown effects such as antioxidant, antitumoral, anti-inflammatory, and immunostimulant. We report for the first time a cytogenetic study to evaluate the radioprotective effect, in vitro, of propolis against radiation-induced chromosomal damage. Lymphocytes were cultured with increasing concentrations of ethanol extract of propolis (EEP), including 20, 40, 120, 250, 500, 750, 1000, and 2000 ¿g mL-1 and then exposed to 2 Gy ¿-rays. A significant and concentration-dependent decrease is observed in the frequency of chromoso…
Mise en évidence et étude d'une isoforme alternative du facteur de transcription IRF-1 dans la différenciation lymphocytaire Th1
2019
It is now clearly established that immune system can affect cancer response to therapy. However, the influence of tumor microenvironment on immune cells is not completely understood. In this respect, alternative splicing is increasingly described to affect immune system biology.Here, we showed that tumor microenvironment, by increasing alternative splicing events, induced the expression of an alternative isoform of the IRF1 transcription factor in Th1 cells. Furthermore, we also showed, in both mice and humans, that IRF1 alternative isoform alters IRF1 full form transcriptional activity on Il12rb1 promotor, resulting in decreased IFN-γ secretion in Th1 cells.Thus, the expression of the IRF1…
Étude de la régulation transcriptionnelle des lymphocytes Th9
2017
CD4 helper T cells support a wide range of functions due to their ability to differentiate into different effector subsets depending on the antigen encountered and the cytokine environment in which they are. Current knowledge on the differentiation of helper T cells highlights the existence of complex transcriptional networks specific to each T helper subset. In 2008, IL-9 secreting CD4 T cells (Th9) are identified as a new helper T cell subtype. Differentiated in the presence of IL-4 and TGF-β, Th9 cells secrete IL-9 and IL-21, and contribute to the development of autoimmune and allergic diseases. Th9 lymphocytes also exhibit strong anti-tumor properties.The transcriptional network of the …
Generation of Cytotoxic T Lymphocytes Against Ly Alloantigen
2008
Cytotoxic T lymphocytes specific for immune alloantigens controlled by alleles of the Ly system have been induced in vivo. These results were obtained either in a secondary type of response or by treating mice before immunization with a single dose of cyclophosphamide (80 mg/kg).