title: Characterization and expression of H-21 region gene products on bone marrow-derived macrophages.
abstract: Antigen-presenting macrophages (M phi) were derived from day 7 cultures of bone marrow stem cells using L cell conditioned medium. The adherent bone marrow-derived macrophages (BMM phi) were 100% esterase-positive, 95% positive for C3 receptors, 93% positive for Fc receptors, and 95% actively phagocytic. Indirect immunofluorescence using anti-Ia monoclonal antibodies resulted in 60% Ia-positive BMM phi on day 7 of stem cell culture. BMM phi could stimulate mixed lymphocyte reaction (MLR) proliferation across an I-A subregion difference, but not across I-J subregion differences. This contrasted with splenic M phi which stimulated MLR proliferation across both an I-A and I-J subregion difference. The apparent lack of I-J subregion determinants on BMM phi correlated with their ability to function as antigen-presenting cells. In these experiments, BMM phi effectively reconstituted the trinitrophenyl-specific IgM plaque-forming cell (PFC) response of B cells but not the primary burro red blood cell (BRBC)-specific IgM-PFC response of M phi-depleted spleen cells. When BMM phi were added to BRBC-primed T and B cells, they reconstituted the secondary IgG PFC response to levels obtained using splenic M phi. These experiments relate the differential expression of H-21 region determinants on antigen-presenting cells with their functional capacity.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D002450:Cell Communication; D005786:Gene Expression Regulation; D005802:Genes, MHC Class II; D006183:H-2 Antigens / Q000235:genetics*; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D066298:In Vitro Techniques; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D006183:H-2 Antigens