CTLA-4 is a negative regulator for T cell activation and plays an important role in down-regulating immune responses and the maintenance of peripheral tolerance. The effect of initial treatment with anti-CTLA-4 mAb on murine acute and chronic graft-versus-host diseases (GVHD) induced by transfer of either C57BL/6 or BALB/c splenocytes into F1 recipient mice has been investigated. The treatment ...

BACKGROUND Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a potent immunoregulatory molecule that suppresses antitumor response by downregulating T cell activation. The most studied +49A>G polymorphism of the CTLA-4 gene has been associated with several autoimmune diseases. However, little is known about the association between this functional polymorphism of CTLA-4 and cancer prognosis. OBJECT...

CTLA-4 is an activation-induced, homodimeric inhibitory receptor in T cells. Recent crystallographic reports have suggested that it may form lattice-like arrays on the cell surface upon binding B7.1/B7.2 (CD80, CD86) molecules. To test the biological relevance of these CTLA-4-B7 lattices, we introduced a C122A point mutation in human CTLA-4, because this residue was shown to be essential for di...

CTLA-4 proteins contribute to the suppressor function of regulatory T cells (Tregs), but the mechanism by which they do so remains incompletely understood. In the present study, we assessed CTLA-4 protein function in both Tregs and conventional (Tconv) CD4 T cells. We report that CTLA-4 proteins are responsible for all 3 characteristic Treg functions of suppression, TCR hyposignaling, and anerg...

CTLA-4 plays an important role in the down-regulation of activated T cells and in the establishment of peripheral tolerance. It has been hypothesized that CTLA-4 on the cell surface signals directly into T cells during primary immune responses, resulting in intrinsic T cell down-regulation. It is not known, however, whether CTLA-4 directly inhibits the less intense activating signals received b...

Recently, "ipilimumab," an anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4) monoclonal antibody, has been demonstrated to improve overall survival in metastatic melanoma. "CTLA-4" is an immune-checkpoint molecule that downregulates pathways of T-cell activation. Ipilimumab, by targeting CTLA-4, is able to remove the CTLA-4 inhibitory signal, allowing the immune system to react to cancer cells. Du...

Cytotoxic T lymphocyte antigen-4 (CTLA-4/CD152) is a member of the CD28 family of T cell effector antigens. Current belief, based primarily on results from gene-deleted mice, is that CTLA-4 promotes suppression of T cell proliferation. In this manuscript, Mark Slifka and colleagues compare antiviral responses of unmanipulated virus-specific CTLA-4 and CTLA-4 T cells. The results of this work su...

INTRODUCTION Spondylarthropathies (SpA) are characterized by abnormal immune responses including T cell activation. Cytotoxic T lymphocyte associated molecule-4 (CTLA-4) is involved in down-regulating immune responses. A soluble form of CTLA-4 (sCTLA-4), resulting from an alternative splicing, has been identified and was found increased in several autoimmune diseases. Here, we evaluated circula...

Successful immune cell control requires a delicate balance of positive and negative regulatory signals. Costimulatory pathways involving molecules such as CD28, inducible costimulator (ICOS), 4-1BB, and CD40L are essential coactivators of proliferation, cytokine production, and cell migration. To balance these signals, cell surface molecules like Fas, tumor necrosis factorreceptor (TNFR), and p...

results our study showed that there were no statistically significant differences in the allele and genotype frequencies of -1661 a/g snp between patients with sle and healthy controls (p > 0.05). conclusions in conclusion, we found no association between snp-1661 a/g of the ctla-4 promoter region and susceptibility to sle in our population. objectives to evaluate the potential influences of co...