Sex hormones enhance immunoglobulin synthesis by human peripheral blood lymphocytes

Using a protein A haemolytic plaque assay to detect immunoglobulin synthesis by human peripheral blood lymphocytes cultured with pokeweed mitogen, we have shown a significant increase in IgG plaque-forming cells in the presence of physiological concentrations of testosterone and oestradiol. Higher concentrations of these steroids inhibit plaque-forming cells. There was no difference in the response to testosterone and oestradiol of lymphocytes derived from male subjects or menstruating or post-menopausal females.