title: Regulation of pre-B cell proliferation in bone marrow: immunofluorescence stathmokinetic studies of cytoplasmic mu chain-bearing cells in anti-IgM-treated mice, hematologically deficient mutant mice and mice given sheep red blood cells.
abstract: To identify factors influencing the in vivo proliferate activity of bone marrow pre-B cells, the metaphase-blocking drug, vincristine sulfate, was injected into (a) mice depleted of B lymphocytes by treatment with anti-mouse IgM antibodies from birth; (b) hematologically deficient W/Wv and Sl/Sld mutants, and (c) mice injected with a foreign agent, sheep red blood cells (SRBC). Subsequently, a quantitative measure of pre-B cell proliferation was provided by examining marrow cells by immunofluorescence labeling for the absolute number of pre-B cells, identified by the presence of cytoplasmic mu chains (c mu) without surface mu (s mu), which had been arrested in metaphase. In anti-IgM-treated mice, some changes were observed in the size of the large pre-B cell population and in the incidence of mitotic cells after vincristine administration, but the overall production rate of pre-B cells did not differ from that in controls given normal rabbit serum. Pre-B cell kinetics in W/Wv and Sl/Sld mice also generally resembled those in homozygous controls. In contrast, after SRBC injection, there was an increase in the rate at which large pre-B cells entered mitosis. Thus, the proliferation of c mu + s mu- bone marrow pre-B cells shows no evidence of feedback control from the mature B lymphocyte pool, as indicated by lack of stimulation of pre-B cell production in anti-IgM-treated mice, and is independent of the hemopoietic defects of W/Wv or Sl/Sld mutants. On the other hand, the increased bone marrow pre-B cell proliferation after SRBC injection demonstrates that the magnitude of B cell genesis in the bone marrow can be influenced by extrinsic agents and thus may be influenced by environmental stimuli.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000276:immunology; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology; D001854:Bone Marrow Cells; D002455:Cell Division; D003593:Cytoplasm / Q000276:immunology; D004912:Erythrocytes / Q000276:immunology; D005246:Feedback; D005260:Female; D006410:Hematopoiesis; D007075:Immunoglobulin M / Q000276:immunology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008817:Mice, Mutant Strains; D011947:Receptors, Antigen, B-Cell / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell