Rajia Bahri

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Human leukocyte antigen G (HLA-G) is a regulatory molecule that is expressed in the cytotrophoblast during implantation and is thought to allow the tolerance and the development of the semiallogeneic embryo. In vitro, HLA-G inhibits natural killer (NK) cell and CD8 T-cell cytotoxicity. HLA-G also decreases CD4 T-cell expansion. This suggests that it(More)
The characteristics, importance, and molecular requirements for interactions between mast cells (MCs) and CD8(+) T cells have not been elucidated. Here, we demonstrated that MCs induced antigen-specific CD8(+) T cell activation and proliferation. This process required direct cell contact and MHC class I-dependent antigen cross-presentation by MCs and(More)
HLA-G is involved in regulating T cell responses. Various mechanisms have been proposed to explain the inhibition of T cell proliferation. In this context, the possible role of HLA-G in cell cycle regulation remains to be explored. Using stably transfected M8 cells expressing the secreted isoform (HLA-G5) of HLA-G, we investigated the role of HLA-G in(More)
Human leukocyte antigen G (HLA-G) is involved in regulating T-cell responses through its interaction with inhibitory receptors belonging to the immunoglobulin-like transcript family (ILT). In this context, we investigated the pathways involved in the control of cell-cycle entry of T cells following HLA-G interaction with its inhibitory receptor. We show(More)
CTLA4-Ig (Belatacept) is a new recombinant molecule that interferes with the signal of T lymphocyte activation and prevents acute rejection after renal transplantation. HLA-G acts as a naturally tolerogenic molecule in humans. In this study, we analyzed whether HLA-G contributes to CTLA4-Ig-mediated graft acceptance. Our results demonstrate that patients(More)
BACKGROUND NK cells have been long time considered as cytotoxic lymphocytes competent in killing virus-infected cells and tumors. However, NK cells may also play essential immuno-regulatory functions. In this context, the real existence of a defined NK subset with negative regulatory properties has been hypothesized but never clearly demonstrated. (More)
Regulatory CD8(+) T cells are critical for self-tolerance and restricting excessive immune responses. The variety of immune functions they fulfill, the heterogeneity of their phenotype, and the mechanism of action are still poorly understood. Here we describe that regulatory CD8(+) T cells exhibiting immunosuppressive actions in vitro and in vivo are(More)
The common gamma (γc)-chain cytokine interleukin 15 (IL15) is a multifunctional immune-modulator which impacts the generation, maturation and activity of many cell types of the innate, as well as the adaptive immune system, including natural killer (NK) and CD8(+) T cells. Using a new series of transgenic mice, we analyzed the in vivo potential of IL15 as(More)
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