Induction of B cell IgA secretion by the culture supernatants of lipopolysaccharide-stimulated peritoneal macrophages.
The regulatory effects of peritoneal macrophage culture supernatant on B-cell growth and IgA secretion were demonstrated in this study. When the LPS-stimulated murine splenic B cells were cultured in medium containing 50% LPS-activated macrophage culture supernatant, both the cell growth and IgM secretion of B cells were suppressed by 64% and 50%, respectively, whereas the IgA secretion was increased 2.6-fold. Transforming growth factor-beta 1 (TGF-beta 1) is a potent regulator of IgA response. Macrophage culture supernatants contained on average 78 ng/ml of TGF-beta 1. When directly added to cultures, TGF-beta 1 also acted as a suppressive factor on B cell growth (55%) but induced an 7.5-fold increase in IgA secretion. Both macrophage culture supernatant and TGF-beta 1 induced an increase in the expression of surface IgA. Further study indicated that the augmenting effect of the macrophage culture supernatant on IgA secretion could be inhibited (50%) by an anti-TGF beta 1 antibody, and that the suppressive effect of the macrophage culture supernatant on the B-cell growth could be overcome by the same antibody, suggesting that TGF-beta 1 was one of the cytokines in the macrophage culture supernatant that regulated B-cell function.
Department of Biology, National Taiwan Normal University, Taipei, Republic of China.
J J
JJ
Shieh
J
J
Tseng
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D007070:Immunoglobulin A / Q000096:biosynthesis*; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000276:immunology; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000096:biosynthesis / Q000276:immunology
D000906:Antibodies; D017077:Culture Media, Conditioned; D007070:Immunoglobulin A; D008070:Lipopolysaccharides; D016212:Transforming Growth Factor beta