title: Selective inhibition of growth factor-dependent human B cell proliferation by monoclonal antibody AB1 to an antigen expressed by activated B cells.
abstract: A monoclonal antibody, AB1, was established with activated human B cells as immunogen. AB1 stained activated B cells but not activated T cells. Its selective reactivity to activated B cells was further documented by its nonreactivity to activated T cells, resting T and B cells, monocytes, granulocytes, bone marrow cells, leukemic cells, and cells from cell lines of T, B, and myeloid lineages. Upon activation, the antigen appeared on B cells as early as 3-4 h after stimulation and was fully expressed by 38 h. The expression of this antigen was not dependent on the presence of B cell stimulatory factor(s). Anti-IgM antibodies by themselves induced its expression. AB1 inhibited B cell proliferation that was induced by a low dose anti-IgM antibody and conditioned medium containing B cell stimulatory factor. It did not inhibit B cell proliferation induced by either high doses of anti-IgM antibodies or by formalinized Staphylococcus aureus. It also failed to inhibit T cell mitogenesis. The possibility exists that this antigen is related to the receptor for B cell stimulatory factor.
mesh_terms: D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000276:immunology*; D002455:Cell Division; D005434:Flow Cytometry; D006133:Growth Substances / Q000276:immunology*; D006801:Humans; D015847:Interleukin-4; D007700:Kinetics; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D006133:Growth Substances; D008222:Lymphokines; D015847:Interleukin-4