title: Changes in the expression of HLA and beta 2-microglobulin by cultured lymphoid cells.
abstract: Changes in the expression of HLA and beta 2-microglobulin (beta 2-m) antigens by cultured human lymphoid cell lines were investigated. HLA expression was assayed by indirect trace binding radioimmunoassay (RIA) with monoclonal antibodies and by determining sensitivity to complement-dependent lysis by alloantisera. Lymphoid cells in culture were found to undergo changes in the expression of HLA and beta 2-m antigens characterized by decreased membrane expression of these antigens at high cell densities or after a prolonged period of cultivation. The decreased expression of HLA and beta 2-m antigens apparently is due neither to a masking phenomenon nor to a lack of nutrients or an accumulation of metabolites in the culture media but is perhaps mediated by a cell-to-cell contact mechanism. Human interferon was found to enhance the expression of HLA and beta 2-m, apparently overriding the effects on major histocompatibility complex (MHC) expression induced by cell density.
mesh_terms: D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000276:immunology; D001609:Beta-Globulins / Q000276:immunology*; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D006680:HLA Antigens; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology; D008214:Lymphocytes / Q000276:immunology*; D011863:Radioimmunoassay; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors; D001613:beta 2-Microglobulin / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D001609:Beta-Globulins; D006680:HLA Antigens; D007370:Interferon Type I; D001613:beta 2-Microglobulin