title: Cloning of B7-2: a CTLA-4 counter-receptor that costimulates human T cell proliferation.
abstract: Although presentation of antigen to the T cell receptor is necessary for the initiation of an immune response, additional molecules expressed on antigen-presenting cells deliver essential costimulatory signals. T cell activation, in the absence of costimulation, results in T cell anergy. The B7-1 protein is a costimulator molecule that regulates interleukin-2 (IL-2) secretion by signaling through the pathway that uses CD28 and CTLA-4 (hereafter referred to as the CD28 pathway). We have cloned a counter-receptor of CD28 and CTLA-4, termed B7-2. Although only 26 percent identical to B7-1, B7-2 also costimulates IL-2 production and T cell proliferation. Unlike B7-1, B7-2 messenger RNA is constitutively expressed in unstimulated B cells. It is likely that B7-2 provides a critical early costimulatory signal determining if the T cell will contribute to an immune response or become anergic.
authors.affiliation: Division of Hematologic Malignancies, Dana-Farber Cancer Institute.
authors.forename: G J
authors.initials: GJ
authors.lastname: Freeman
authors.forename: J G
authors.initials: JG
authors.lastname: Gribben
authors.forename: V A
authors.initials: VA
authors.lastname: Boussiotis
authors.forename: J W
authors.initials: JW
authors.lastname: Ng
authors.forename: V A
authors.initials: VA
authors.lastname: Restivo
authors.forename: L A
authors.initials: LA
authors.lastname: Lombard
authors.forename: G S
authors.initials: GS
authors.lastname: Gray
authors.forename: L M
authors.initials: LM
authors.lastname: Nadler
mesh_terms: D000069594:Abatacept; D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000378:metabolism*; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D018122:B7-1 Antigen / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D051940:B7-2 Antigen; D018106:CD28 Antigens / Q000378:metabolism; D060908:CTLA-4 Antigen; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D018796:Immunoconjugates; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D016415:Sequence Alignment; 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; D018076:DNA, Complementary; D018796:Immunoconjugates; D008562:Membrane Glycoproteins; D000069594:Abatacept