title: T-cell regulation by CD28 and CTLA-4.
abstract: Activation of T lymphocytes is thought to require at least two signals, one delivered by the T-cell receptor complex after antigen recognition, and one provided on engagement of co-stimulatory receptors, such as CD28. Recent studies are providing clues as to the specific signalling roles of co-stimulatory receptors. Furthermore, superimposition of inhibitory signals, such as those delivered by cytotoxic T-lymphocyte antigen 4 (CTLA-4), leads to a complex network of positive and negative co-stimulatory signals, the integration of which modulates immune responses.
authors.affiliation: Department of Medicine, Section of Rheumatology and Committee in Immunology, Chicago, Illinois 60637, USA. malegre@midway.uchicago.edu
authors.forename: M L
authors.initials: ML
authors.lastname: Alegre
authors.forename: K A
authors.initials: KA
authors.lastname: Frauwirth
authors.forename: C B
authors.initials: CB
authors.lastname: Thompson
mesh_terms: D000069594:Abatacept; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D000943:Antigens, Differentiation / Q000378:metabolism*; D018122:B7-1 Antigen / Q000378:metabolism; D051940:B7-2 Antigen; D018106:CD28 Antigens / Q000378:metabolism*; D060908:CTLA-4 Antigen; D006801:Humans; D007108:Immune Tolerance; D018796:Immunoconjugates; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D018448:Models, Immunological; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D018106:CD28 Antigens; C497964:CD86 protein, human; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; C497965:Cd86 protein, mouse; C556707:Ctla4 protein, mouse; D018796:Immunoconjugates; D008562:Membrane Glycoproteins; D011948:Receptors, Antigen, T-Cell; D000069594:Abatacept