A critique of the use of DNA synthesis as a measure of the effect of mitogens on lymphocytes

Abstract
The use of DNA synthesis as a measure of mitogenic activity in human and animal lymphocytes is reanalyzed in the light of the continuum model. Although lymphocytes may have a linear response with regard to mitogen concentration, the curves using thymidine may show a threshold response at low concentrations and a decrease in activity at high concentrations.