B cell growth factor and T cell growth factor produced by mitogen-stimulated normal human peripheral blood T lymphocytes are distinct molecules.
Using a recently described assay for inducing and measuring the proliferation of normal human B cells in the absence of differentiation, we have demonstrated that B cell growth factor (BCGF) activity can be obtained from the culture of human peripheral blood mononuclear cells in the presence of mitogens. Using Sephacryl S-200 gel filtration, BCGF activity was demonstrated in the 20 to 30K m.w. fractions of mitogen-stimulated peripheral blood mononuclear cells. However, this fraction also showed substantial T cell growth factor (TCGF) activity. Despite this overlapping of m.w., BCGF activity could clearly be separated from TCGF activity by selective absorption of factor-containing supernatants with the interleukin 2 activity by using interleukin 2-dependent cells without any diminution of BCGF activity, strongly suggesting that these two factors may be distinct molecular entities.
D001402:B-Lymphocytes / Q000276:immunology*; D006133:Growth Substances / Q000276:immunology*; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology* / Q000302:isolation & purification; D015847:Interleukin-4; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
D006133:Growth Substances; D007376:Interleukin-2; D015847:Interleukin-4