title: Regulation of bone marrow lymphocyte production. IV. Cells mediating the stimulation of marrow lymphocyte production by sheep red blood cells: studies in anti-IgM-suppressed mice, athymic mice, and silica-treated mice.
abstract: Some cellular requirements have been examined for the stimulation of lymphocyte production in mouse bone marrow by injected sheep red blood cells (SRBC). The increased genesis of marrow lymphocytes after a single dose of SRBC assayed radioautographically after [3H]thymidine labeling was unimpaired in the marrow of mice treated with anti-IgM antibodies from birth to eliminate B lymphocytes, and in congenitally athymic mice lacking T lymphocytes. However, pretreatment of mice with silica to depress macrophage function completely abolished the SRBC effect both on the total lymphocyte production and on the number of B and null small lymphocytes in the marrow. Comparative studies were performed on the thymus and spleen. The results demonstrate that the stimulation of marrow lymphocytes production by SRBC is mediated by a silica-sensitive mechanism, does not require B or T lymphocytes, and is independent of the humoral immune response. Thus, extrinsic agents may amplify the production of primary B cells and other lymphocytes in the bone marrow by an antigen-nonspecific mechanism, putatively mediated by macrophages.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000008:administration & dosage*; D001854:Bone Marrow Cells; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D007075:Immunoglobulin M / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000145:classification / Q000276:immunology*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D011817:Rabbits; D012822:Silicon Dioxide / Q000494:pharmacology; D013154:Spleen / Q000166:cytology; D013950:Thymus Gland / Q000166:cytology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007075:Immunoglobulin M; D012822:Silicon Dioxide