Role of the CTLA-4 receptor in T cell activation and immunity. Physiologic function of the CTLA-4 receptor.
Costimulatory molecules of the B7 family regulate the activation of T lymphocytes. T cell activation is promoted by binding of B7 molecules to CD28 and inhibited by binding to CTLA-4 (CD152). The balance between positive signals through CD28 and negative signals through CTLA-4 is critical for the fate of the T cell and is subject to tight regulation. Recent in vitro and in vivo studies have significantly advanced our understanding of the function of the CTLA-4 receptor. The results of these experiments suggest that CTLA-4 is critical for the induction of self-tolerance, and that it may have distinct signaling functions in resting and activated T cells. In resting T cells, CTLA-4 crosslinking leads to cell-cycle arrest, whereas in activated T cells, CTLA-4 crosslinking induces apoptosis. In this article, we will review the physiologic functions of the CTLA-4 receptor.
Scheipers
P
P
Department of Immunology, Imperial College School of Medicine, Hammersmith Hospital, London, UK.
Reiser
H
H
D000069594:Abatacept; D000818:Animals; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000737:chemistry / Q000502:physiology*; D017209:Apoptosis; D060908:CTLA-4 Antigen; D006801:Humans; D007108:Immune Tolerance / Q000502:physiology; D018796:Immunoconjugates; D008213:Lymphocyte Activation; D051379:Mice; D051381:Rats; D015398:Signal Transduction / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology
D015703:Antigens, CD; D000943:Antigens, Differentiation; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; C556707:Ctla4 protein, mouse; D018796:Immunoconjugates; D000069594:Abatacept