title: Identification of an alternative CTLA-4 ligand costimulatory for T cell activation.
abstract: Stimulation of T cell proliferation generally requires two signals: The first signal is provided by the T cell receptor binding to antigen, and the second signal or costimulus is provided by a different receptor-ligand interaction. In mouse and human, the CD28-B7 interaction has been identified as a source of costimulatory signals. We have identified a cell surface molecule (GL1) that is distinct from B7 and abundantly expressed on activated B cells. On activated B cells GL1, rather than B7, is the predominant ligand for the T cell-activation molecule CTLA-4. GL1 provides a critical signal for T cell-dependent responses in vitro and in vivo.
authors.affiliation: Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
authors.forename: K S
authors.initials: KS
authors.lastname: Hathcock
authors.forename: G
authors.initials: G
authors.lastname: Laszlo
authors.forename: H B
authors.initials: HB
authors.lastname: Dickler
authors.forename: J
authors.initials: J
authors.lastname: Bradshaw
authors.forename: P
authors.initials: P
authors.lastname: Linsley
authors.forename: R J
authors.initials: RJ
authors.lastname: Hodes
mesh_terms: D000069594:Abatacept; D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000378:metabolism; D000943:Antigens, Differentiation / Q000378:metabolism*; D000954:Antigens, Surface / Q000276:immunology / Q000378:metabolism*; D001402:B-Lymphocytes / Q000276:immunology*; D018122:B7-1 Antigen / Q000276:immunology / Q000378:metabolism*; D018821:CD18 Antigens; D016466:CHO Cells; D060908:CTLA-4 Antigen; D006224:Cricetinae; D018796:Immunoconjugates; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000943:Antigens, Differentiation; D000954:Antigens, Surface; D018122:B7-1 Antigen; D018821:CD18 Antigens; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; C556707:Ctla4 protein, mouse; D018796:Immunoconjugates; D007376:Interleukin-2; D000069594:Abatacept