Inhibition of the proliferative response of human B lymphocytes to B cell growth factor by transforming growth factor‐beta

Abstract

The effects of transforming growth factor‐beta (TGF‐β) on the proliferative response of human B cells to the low molecular weight B cell growth factor (BCGF) have been investigated in this study. It was found that TGF‐β”, at picomolar concentrations, strongly inhibited the BCGF‐induced proliferation of anti‐μ. chain or Staphylococcus aureus Cowan I‐activated human B cells and also of a BCGF‐dependent cell line derived from a human lymphocytic nodular lymphoma. This inhibitory effect was detected in normal and serum‐free culture conditions. The suppression was greatly reduced when TGF‐β was added to the culture one day after BCGF and could be reverted by removing TGF‐β from the culture medium. Since TGF‐β has been detected in supernatants from activated T cells, this factor may represent an important regulatory molecule in the feedback control of B cell activation.