Clonal analysis of B cells induced to secrete IgG by T cell-derived lymphokine(s).
To gain insight into how T cell-derived lymphokines induce the secretion of IgG in activated B cells, we performed a limiting dilution analysis, using murine splenic B cells incubated with lipopolysaccharide (LPS) and a T cell-derived B cell differentiating factor for IgG (BCDF gamma)-containing supernatant (SN). The results of this analysis indicate that such a SN induces a marked increase in the precursor frequency of IgG1-secreting cells and a modest increase in clone size. The precursors lack surface IgG and are committed to the differentiation pathway for IgG1 secretion after LPS activation, but before the addition of BCDF gamma-containing SN. The majority of IgG1-secreting clones arise independently from precursors of cells that secrete IgG3. Taken together, these results indicate that BCDF gamma directs differentiation of activated B cells to IgG1 secretion.
D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface / Q000494:pharmacology; D001402:B-Lymphocytes / Q000276:immunology*; D002999:Clone Cells / Q000276:immunology*; D005260:Female; D007074:Immunoglobulin G / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008222:Lymphokines / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D051381:Rats; D011917:Rats, Inbred Lew; D013601:T-Lymphocytes / Q000378:metabolism*
D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface; D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D008222:Lymphokines