title: Intercellular adhesion molecule 1 is critical for activation of CD28-deficient T cells.
abstract: Presentation of Ag to T lymphocytes in the absence of the requisite costimulatory signals leads to an Ag-specific unresponsiveness termed anergy, whereas Ag presentation in conjunction with costimulation leads to clonal expansion. B7/CD28 signaling has been shown to provide this critical costimulatory signal and blockade of this pathway may inhibit in vitro and in vivo immune responses. Although T cells from CD28-deficient mice are lacking in a variety of responses, they nonetheless are capable of various primary and secondary responses without the induction of anergy expected in the absence of costimulation. This suggests that there may be alternative costimulatory pathways that can replace CD28 signaling under certain circumstances. In this paper, we show that ICAM-1becomes a dominant costimulatory molecule for CD28-deficient T cells. ICAM-1 costimulates anti-CD3-mediated T cell proliferation and IL-2 secretion in CD28-deficient murine T cells. Furthermore, splenocytes from ICAM-1-deficient mice could not activate CD28-deficient T cells and splenocytes lacking both ICAM and CD28 fail to proliferate in response to anti-CD3-induced T cell signals. This confirms that not only can ICAM-1 act as a CD28-independent costimulator, but it is the dominant, requisite costimulatory molecule for the activation of T cells in the absence of B7/CD28 costimulation.
authors.affiliation: Departments of Neurology and Pathology, Center For Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Gaglia
authors.forename: E A
authors.initials: EA
authors.lastname: Greenfield
authors.forename: A
authors.initials: A
authors.lastname: Mattoo
authors.forename: A H
authors.initials: AH
authors.lastname: Sharpe
authors.forename: G J
authors.initials: GJ
authors.lastname: Freeman
authors.forename: V K
authors.initials: VK
authors.lastname: Kuchroo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis / Q000235:genetics; D018122:B7-1 Antigen / Q000096:biosynthesis / Q000235:genetics; D051940:B7-2 Antigen; D018106:CD28 Antigens / Q000096:biosynthesis* / Q000235:genetics* / Q000502:physiology; D017252:CD3 Complex / Q000276:immunology; D016466:CHO Cells; D019556:COS Cells; D002522:Chlorocebus aethiops; D006224:Cricetinae; D007106:Immune Sera / Q000494:pharmacology; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000378:metabolism; D008213:Lymphocyte Activation / Q000235:genetics; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D017452:Receptors, IgG / Q000096:biosynthesis / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism*; D014162:Transfection
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D018106:CD28 Antigens; D017252:CD3 Complex; C497965:Cd86 protein, mouse; D007106:Immune Sera; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D017452:Receptors, IgG; D018799:Intercellular Adhesion Molecule-1