title: Regulation of T:B cell interactions by the inducible costimulator molecule: does ICOS "induce" disease?
abstract: The Inducible Costimulator molecule (ICOS), a member of the CD28 family of costimulatory molecules, was identified in 1999 as a molecule expressed primarily on activated human T cells. Induced upon activation, ICOS appears to be an ideal target for modifying T-cell-mediated immune responses. ICOS was also found to be highly expressed on germinal center T cells, suggesting that ICOS was involved in T:B cell interactions. While ICOS has subsequently been shown to be important for both Th1 and Th2 cell activation and effector function, a central role for ICOS in the generation and maintenance of humoral immunity is emerging. In this review, we summarize the evidence that the level of ICOS expression regulates T-cell-dependent B cell responses and propose a model for the role of ICOS in diseases characterized by dysregulated humoral immunity.
authors.affiliation: Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago MC 6076, 5841 S. Maryland Ave, Chicago, IL 60637, USA. eshillin@medicine.bsd.uchicago.edu
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Shilling
authors.forename: Hozefa S
authors.initials: HS
authors.lastname: Bandukwala
authors.forename: Anne I
authors.initials: AI
authors.lastname: Sperling
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000502:physiology*; D001327:Autoimmune Diseases / Q000378:metabolism*; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002450:Cell Communication / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000378:metabolism*; D060889:Inducible T-Cell Co-Stimulator Protein; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; C556692:ICOS protein, human; D060889:Inducible T-Cell Co-Stimulator Protein