title: Constitutive alpha V beta 3 integrin-mediated adhesion of human lymphoid B cells to vitronectin substrate.
abstract: Adherence to cells and matrices participates in lymphocyte migration and tissue localization and contributes to the regulation of growth and differentiation of the lymphoid cells. The adherence is mainly mediated by three families of cell-surface proteins: integrins, immunoglobulin (Ig)-related molecules, and selectins. Integrins recognize Ig-related molecules such as ICAMs as well as fibronectin (FN), vitronectin (VN), and other matrix proteins. In this study, the in vitro adhesive properties of two Epstein-Barr virus-carrying B lymphoblastoid cell lines, IB-4 and NAD-20, were compared. IB-4 cells grow as a monolayer in contrast to NAD-20 cells, which grow as cell clusters. IB-4 cells were found to adhere to the tissue culture vessel through a component of the fetal bovine serum. By using blocking monoclonal antibodies to cell-surface molecules and serum proteins, IB-4 cells were found to use alpha V beta 3 integrin (CD51/CD61) and serum VN as the adhesive molecules. alpha V beta 3 integrin also mediated adhesion of IB-4 cells to human serum VN and to purified VN and FN. This constitutive adherence was not enhanced by phorbol ester treatment and was inhibited by RGD-containing peptides, in contrast to the homotypic adhesion of NAD-20 cells, which was mediated by beta 2 integrin CD11a/CD18 and its ligand ICAM-1 (CD54). Since VN is a component of both lymphoid tissue matrix and plasma, adhesion to this protein may affect functions and activities of B lymphocytes.
authors.affiliation: Microbiology and Tumor Biology Center, Karolinska Institutet, Stockholm, Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Salcedo
authors.forename: M
authors.initials: M
authors.lastname: Patarroyo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D001798:Blood Proteins / Q000502:physiology; D018845:CD11 Antigens / Q000502:physiology; D018821:CD18 Antigens; D002417:Cattle; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000502:physiology*; D002461:Cell Line, Transformed; D004492:Edetic Acid / Q000494:pharmacology; D005312:Fetal Blood / Q000502:physiology; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D016023:Integrins / Q000276:immunology / Q000502:physiology*; D018799:Intercellular Adhesion Molecule-1 / Q000502:physiology; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000494:pharmacology; D016024:Receptors, Cytoadhesin / Q000276:immunology / Q000502:physiology*; D019030:Receptors, Vitronectin; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D019096:Vitronectin
chemical_list: D000911:Antibodies, Monoclonal; D001798:Blood Proteins; D018845:CD11 Antigens; D018821:CD18 Antigens; D015815:Cell Adhesion Molecules; D006023:Glycoproteins; D016023:Integrins; D009842:Oligopeptides; D016024:Receptors, Cytoadhesin; D019030:Receptors, Vitronectin; D019096:Vitronectin; D018799:Intercellular Adhesion Molecule-1; C047981:arginyl-glycyl-aspartic acid; C058161:glycyl-arginyl-glycyl-aspartyl-seryl-proline; C058347:glycyl-arginyl-glycyl-glutamyl-seryl-proline; D004492:Edetic Acid; D013755:Tetradecanoylphorbol Acetate