A monoclonal T cell-replacing activity can act directly on B cells to enhance clonal expansion.
We have used a B cell cloning system in which the response of a single isolated B cell to lipopolysaccharide and dextran sulfide can be followed. We have shown that culture supernatants from the Dennert long-term alloreactive T cell line C.C3.11.75 increase the frequency of B cells stimulated to clonal expansion by mitogens. These culture supernatants are devoid of interleukin 1 and 2 but contain the T cell-replacing factor activity (DL)TRF. These experiments provide unequivocal proof that a T cell-derived factor or factors can act directly on a B lymphocyte in the absence of any other cell.
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002452:Cell Count; D002460:Cell Line; D002999:Clone Cells / Q000276:immunology; D005260:Female; D015848:Interleukin-5; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA
D015848:Interleukin-5; D008222:Lymphokines