Serum-free culture of hamster lymphoid cells and differential inhibition of lipopolysaccharide stimulation by isologous serum.
The optimal conditions for serum-free cultures of hamster lymphoid cells were determined. The cells responded to both the nonspecific thymus-derived lymphocyte mitogen concanavalin A (Con A) and the nonspecific bone marrow-derived lymphocyte mitogens lipopolysaccharide (LPS) and dextran sulfate (DxS). Normal MHA hamster serum was shown to specifically inhibit the response to LPS and DxS by 95% without inhibiting the response to Con A. The serum also did not inhibit one-way mixed lymphocyte reaction. Incubation of cells in 5% serum for short periods of time, followed by serum-free culture, did not lead to inhibition. The serum inhibited the LPS response by 65% even when added 24 h after initiation of the culture. The activity was associated with the high-molecular-weight material on Sephadex G-200 fractionation of serum. The inhibitory fraction did not possess antibody activity to LPS. The possibility that the material is an alpha2-macroglobulin is discussed.
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001667:Binding, Competitive; D002478:Cells, Cultured; D002850:Chromatography, Gel; D003208:Concanavalin A / Q000494:pharmacology; D006224:Cricetinae / Q000097:blood*; D003470:Culture Media; D003911:Dextrans / Q000494:pharmacology; D005260:Female; D007165:Immunosuppression Therapy; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D013045:Species Specificity; D013997:Time Factors
D000907:Antibodies, Bacterial; D003470:Culture Media; D003911:Dextrans; D008070:Lipopolysaccharides; D003208:Concanavalin A