title: Ia antigen expression is increased on tunicamycin-resistant human B-lymphoid cells.
abstract: Cultured human B-lymphoid cells WIL-2 were mutated with ethylmethane sulfonate and selected for resistance to tunicamycin, an antibiotic that selectively inhibits N-linked glycosylation. Ultrastructural analysis of five isolated tunicamycin-resistant mutants (TMR) showed changes in surface microvilli, dilation of the endoplasmic reticulum, and an increase in surface myelin figures. Cytofluorometric analysis of TMR cells incubated with anti-HLA monoclonal antibodies showed a normal density of HLA-A, B antigens and an increased density of Ia antigens. The properties of these TMR mutants have remained stable for at least 18 months. These TMR cells may serve as a useful model to study the biochemical events in the processing and expression of Ia antigens.
mesh_terms: D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000276:immunology* / Q000648:ultrastructure; D004351:Drug Resistance; D005944:Glucosamine / Q000031:analogs & derivatives*; D006680:HLA Antigens / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D009154:Mutation; D014415:Tunicamycin / Q000494:pharmacology*
chemical_list: D000911:Antibodies, Monoclonal; D006680:HLA Antigens; D000949:Histocompatibility Antigens Class II; D014415:Tunicamycin; D005944:Glucosamine