Virus-specific cluster of differentiation 8 (CD8+) cytotoxic T cells (CTL) recognize viral antigens presented on major histocompatibility complex (MHC) class I chains on infected hepatocytes, with help from CD4+ T cells. However, this CTL response is frequently weak or undetectable in patients with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. Programmed cell death 1 (P...

Chronic T cell responses, as they occur in rheumatoid arthritis, are complex and are likely to involve many mechanisms. There is a growing body of evidence that, in concert with the T cell antigen receptor signal, CD28 and cytotoxic T-lymphocyte antigen-4 (CTLA-4; CD152) are the primary regulators of T cell responses. Whereas CD28 primarily activates T cell processes, CTLA-4 inhibits them. The ...

Crosslinking ligand-engaged cytotoxic T lymphocyte antigen-4 (CTLA-4) to the T cell receptor (TCR) with a bispecific fusion protein (BsB) comprised of a mutant mouse CD80 and lymphocyte activation antigen-3 (LAG-3) has been shown to attenuate TCR signaling and to direct T-cell differentiation toward Foxp3(+) regulatory T cells (Tregs) in an allogenic mixed lymphocyte reaction (MLR). Here, we sh...

CD4 T cells activated in vitro by anti-CD3/28-coated beads are resistant to infection by CC chemokine receptor 5 (CCR5)-dependent HIV-1 isolates. In vivo, antigen-presenting cells (APCs) activate CD4 T cells in part by signaling through the T cell receptor and CD28, yet cells stimulated in this manner are susceptible to HIV-1 infection. We show that cytotoxic T lymphocyte antigen 4 (CTLA-4) eng...

Cytotoxic T lymphocyte antigen 4 (CTLA-4) is an important regulator of T cell homeostasis. Ligation of this receptor leads to prominent downregulation of T cell proliferation, mainly as a consequence of interference with IL-2 production. We here report that CTLA-4 engagement strikingly selectively shuts off activation of downstream T cell receptor (TCR)/CD28 signaling events, i.e., activation o...

Metastatic cutaneous melanoma has poor prognosis with 2-year survival rate of 10-20%. Melanoma cells express various antigens including gp100, melanoma antigen recognized by T cells 1 (MART-1), and tyrosinase, which can induce immune-mediated anticancer response via T cell activation. Cytotoxic T-lymphocyte associated antigen-4 (CTLA-4) is an immune check point molecule that negatively regulate...

Background: It is thought that a limited number of aberrant cancer stem cells (CSCs), which encourage carcinogenesis, tumor metastasis, and treatment resistance, are the cause pancreatic cancer, disease with high mortality rate. Increasing evidence shows CSCs use immunosuppressive properties to avoid immune system identification. In Pancreatic therapeutic consequences relationship between expre...

Type 1 Diabetes (T1D) is a serious chronic disease that results from an autoimmune destruction of the insulin-producing beta cells. Sweden has the second highest incidence of T1D in the world, and it affects more and more children each year. Genes controlling key functions of the immune system regulation of autoimmunity has been associated to T1D. Polymorphism in the Human Leukocyte Antigen (HL...

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4; CD152) is of pivotal importance for self-tolerance, with deficiency or unfavorable polymorphisms leading to autoimmune disease. Tolerance to self-antigens is achieved through thymic deletion of highly autoreactive conventional T (Tconv) cells and generation of FoxP3(+) regulatory T (Treg) cells. The main costimulatory molecule, CD28, augments...

Cytotoxic T lymphocyte antigen-4 (CTLA-4) is an inhibitory receptor on T cells essential for maintaining T cell homeostasis and tolerance to self. Mice lacking CTLA-4 develop an early onset, fatal breakdown in T cell tolerance. Whether this autoimmune disease occurs because of the loss of CTLA-4 function in regulatory T cells, conventional T cells, or both is unclear. We show here that lack of ...