Phytohemagglutinin - Stimulated Normal Human Peripheral Blood Lymphocytes in Folate - Depleted Medium : An In Vitro

Normal human peripheral blood lymphocytes cultured with phytohemagglutinin in folate-free RPMI 1 640 medium supplemented with normal human serum exhibit megaloblastic maturation. These changes are accompanied by a decrease in intracellular folate content. and when compared to folate-replete cells. reveal increased 3H-thymidine incorporation into DNA together with a decreased inhibitory effect of deoxyuridine on 3H-thymidine incorporation This in vitro system of cellular folate deficiency is a convenient model for analysis of biochemical events accompanying megaloblastic maturation.