title: In vitro response of human peripheral blood lymphocytes of protein A. DNA synthesis and generation of cells synthesizing the three major classes of Ig.
abstract: Increased DNA synthesis and immunoglobulin secretion was observed in human peripheral blood lymphocytes (PBL) cultured in vitro with soluble protein A from Staphylococcus aureus (Sp-A). Optimal Ig secretion was obtained in 6 day cultures containing 1 x 10(6) cells/ml and 10 microgram/ml Sp-A. The presence of 5 x 10(-5) M 2-mercaptoethanol in the culture medium as well as careful selection of foetal calf serum were needed for optimal results. In response to Sp-A stimulation, the three main classes of immunoglobulins were secreted by PBL. In some individuals, concentration of Sp-A optimal for IgG and IgM secretion inhibited IgA production. Immunoglobulin-containing cells were less abundant (0.5--5% of total cells) and smaller in Sp-A than in PWM-stimulated cultures (5--15%). The data suggest that Sp-A and PWM stimulated different subsets of circulating lymphocytes.
mesh_terms: D002478:Cells, Cultured; D003470:Culture Media; D004247:DNA / Q000096:biosynthesis*; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology* / Q000378:metabolism; D011043:Pokeweed Mitogens / Q000494:pharmacology; D013205:Staphylococcal Protein A / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D003470:Culture Media; D007136:Immunoglobulins; D011043:Pokeweed Mitogens; D013205:Staphylococcal Protein A; D004247:DNA