Protein synthesis and secretion by activated human lymphocytes

Human peripheral blood mononuclear cells showed increased synthesis and secretion of protein in response to stimulation by mitogens. Protein secretion in response to concanavalin A (Con A) correlated with cellular proliferation and originated from the proliferating cells. Selective depletion of either B lymphocytes or monocytes did not lead to a reduction in the total protein secreted, suggesting that the T lymphocyte was the cell contributing most of the synthetic activity. It is concluded that the measurement of newly synthesized and secreted protein by Con A activated mononuclear cells is a measurement of the T-lymphocyte response.