[Effect of the nucleic factor on lymphocyte cytotoxicity]

Under study was the influence of the nucleic factor, isolated from Ehrlich tumor ascitic fluid, on cytotoxicity of in vitro lymphocytes of CC57Br mice immunized by L-cells. In a dose of 5--10 mkm/ml this factor was shown to suppress cytotoxicity of splenic cells as well as that of lymph nodes cells of previously immunized mice. Cellular DNA of non-lineal SHR mice, hepatic RNA of normal mice C3Ha (their genotype being similar to L-cells), of non-lineal SHR mice and syngeneic CC75Br in the same concentration failed to produce such effect.