title: IFN-gamma stimulates IgG2a secretion by murine B cells stimulated with bacterial lipopolysaccharide.
abstract: rIFN-gamma strikingly enhances the secretion of IgG2a by murine splenic B cells stimulated with bacterial LPS in vitro and concomitantly suppresses the production of IgG3, IgG1, IgG2b, and IgE while sparing IgM secretion. IFN-gamma stimulates highly purified B cell populations to secrete IgG2a, strongly suggesting that it acts directly on B cells. It increases the frequency of precursors of IgG2a-expressing soft agar colonies and enhances the number of IgG2a+ cells in colonies indicating that it both increases the frequency of precursors of IgG2a+ cells and enhances the number of IgG2a+ daughter cells emerging from each precursor. IFN-gamma completes its action within the first 24 to 48 h of a 6-day culture with LPS and its addition cannot be delayed beyond the first 48 h. Preincubation of resting B cells in the presence of IFN-gamma leads to a time dependent increase, up to 42 h, in IgG2a secretion upon subsequent addition of LPS. IFN-gamma can exert this action on resting B cells that have been selected for absence of membrane IgG expression by cell sorting. The promotion of IgG2a secretion appears to be a specific property of IFN-gamma in that IFN-alpha, IFN-beta, IL-1, IL-2, IL-3, IL-4, IL-5, granulocyte-macrophage-CSF, granulocyte-CSF, and CSF-1 fail to enhance IgG2a secretion by LPS-stimulated B cells.
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D001402:B-Lymphocytes / Q000145:classification / Q000378:metabolism* / Q000502:physiology; D002470:Cell Survival; D002478:Cells, Cultured; D005260:Female; D007074:Immunoglobulin G / Q000032:analysis / Q000096:biosynthesis*; D007132:Immunoglobulin Isotypes / Q000032:analysis / Q000096:biosynthesis; D007371:Interferon-gamma / Q000494:pharmacology*; D007399:Interphase / Q000187:drug effects; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008805:Mice, Inbred A; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D013045:Species Specificity
chemical_list: D000276:Adjuvants, Immunologic; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes; D008070:Lipopolysaccharides; D011947:Receptors, Antigen, B-Cell; D007371:Interferon-gamma