title: Monoclonal anti-actin antibody recognizes a surface molecule on normal and transformed human B lymphocytes: expression varies with phase of cell cycle.
abstract: A monoclonal anti-actin antibody, 2C9, was used to study the distribution of an actin-like cell-surface antigen (hereafter termed actin) on a lymphoblastoid cell line LA350 and on human peripheral blood lymphocytes. It was determined that 8-40% of LA350 cells and 3-15% of peripheral blood lymphocytes from healthy donors stain specifically with 2C9, almost exclusively on IgM-positive cells. Treatment of cells with 2C9 prior to incubation caused cell-surface actin to first patch and then to cap. Treatment of cells with nonspecific protease caused a loss of surface actin, with reexpression of the marker after 8-12 hr. The expression of LA350 surface actin also increased with DNA synthesis and was demonstrated to be maximal during late G1/early S phase. Thus, this antigen may be a sensitive marker for activated lymphocytes. These studies contribute to our understanding of the expression and distribution of actin-like membrane proteins that may participate in regulatory signals mediated by anti-actin antibody.
mesh_terms: D000199:Actins / Q000032:analysis* / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000954:Antigens, Surface / Q000032:analysis*; D001402:B-Lymphocytes / Q000276:immunology*; D002453:Cell Cycle; D002460:Cell Line; D004247:DNA / Q000032:analysis; D006801:Humans; D051379:Mice
chemical_list: D000199:Actins; D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D004247:DNA