Stimulation of human lymphocytes in vitro by purified autologous DNA

Addition of increasing concentrations of autologous DNA, but not of allogeneic DNA, in culture media of human lymphocytes induces a parallel increase of thymidine incorporation into leucocytes and of lymphocytes transformation into blast cells. Specificity of DNA action was analysed by different DNase and RNase treatments. DNase or RNase alone neither stimulates blastic transformation of lymphocytes and incorporation of thymidine into leucocytes, nor inhibits PHA-induced stimulations of these cells. However Dnase--but almost not RNase--clearly inhibits thymidine incorporation and blast transformation induced by autologous DNA.