The immune suppressive protein CTLA-4 is constitutively expressed by Tregs and induced in effector T cells upon activation. Its crucial role in adaptive immunity is apparent from the fatal autoimmune pathology seen in CTLA-4 knockout mice. However, little is known regarding factors that regulate CTLA-4 expression and their effect upon its function to remove CD80 and CD86 from antigen presenting...

We present a theoretical framework for simulating the synaptic accumulation of the costimulatory molecules CD28, CTLA-4, B7-1, and B7-2, based on a system of mean-field, ordinary differential equations, and rigorous biophysical and expression data. The simulations show that binding affinity, stoichiometric properties, expression levels, and, in particular, competition effects all profoundly inf...

The T cell co-stimulatory receptors CD28 and CTLA-4 appear to have opposite effects on T cell activation, mediating augmentation and inhibition of T cell responses respectively. Since these two receptors use the same ligands, CD80 (B7-1) and CD86 (B7-2), the co-ordinate timing of CD28 and CTLA-4 expression has a major impact on the regulation of immune responses. While the kinetics of co-stimul...

Cytokine-induced killer (CIK) cells are in vitro-expanded cells harboring potent toxicity against tumor cells. Recently, it was identified that the cytotoxicity and proliferation of CIK cells are restricted by a prolonged CIK cell culture period. Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) serves a negative role in T cell activation and proliferation. This study aims to determine wheth...

This antitumor effect of sorafenib is considered to be dependent not only on its direct cytotoxicity to cancer cells but also due to the inhibition of myeloid-derived suppressor cells (MDSCs). Recently, a novel antibody against cytotoxic T-lymphocyte antigen 4 (CTLA-4), which activates lymphocytes, is currently in clinical applications. The aim of the present study was to investigate the synerg...

The cytotoxic T lymphocyte antigen-4 (CTLA-4) molecule on T cells acts to maintain homeostasis by regulating the proliferation of recently activated T cells. Blockade of CTLA-4 by anti-CTLA-4 antibody enhances T cell responses and has elicited significant tumor regression in some cancer patients. Clinical trials are ongoing to investigate the efficacy of anti-CTLA-4 antibody as a cancer therape...

OBJECTIVE Functionally impaired Treg cells expressing abnormally low levels of CTLA-4 have been well documented in rheumatoid arthritis (RA). However, the molecular defect underlying this reduced expression is unknown. The aims of this study were to assess the role of DNA methylation in regulating CTLA-4 expression in Treg cells isolated from RA patients and to elucidate the mechanism of their ...

background: immunological factors are important in pregnancy loss because of the interaction between mother and fetus. t-regulatory cells as the component of humeral immune response play important role in the fetu-maternal interface. one of the regulatory mechanisms for these cells is mediated by antigen independent co-stimulatory signals and interaction of cytotoxic t-lymphocyte antigen 4 (b7/...

conclusions according to the results, the polymorphisms within the +49 position of ctla-4 can be associated with vl and may be considered as risk factors for the disease. results our results indicated that both ctla-4 +49a/g polymorphisms were significantly associated with vl. materials and methods in this cross-sectional study, 88 patients with clinical presentations of vl, who were seropositi...

allergic rhinitis (ar) is an ige-mediated upper airway disease, and its impact on asthma has been widely recognized. protein tyrosine phosphatase non-receptor 22 (ptpn22) gene and the cytotoxic t-lymphocyte–associated antigen 4 (ctla-4) gene polymorphisms have been reported to be associated with several immune-related diseases. here we investigated the reffect of these two genes’ polymorphisms ...