[Effect of interferon on the inhibition of tumor cell growth by human peripheral leukocytes].

Human leukocyte interferon (HL-IF) enhanced the growth inhibition of tumor cells by the human peripheral leukocytes. There was a dose relation between the enhancement of the growth inhibition of tumor cells and the antiviral activity of interferon. When the ratio of lymphocyte to tumor cell was 10:1 or 50:1, it was recognized that HL-IF enhanced the growth inhibition of tumor cells by lymphocyte. The heterologous IFs--mouse and rabbit IFs--or heat-inactivated or trypsinized IF did not enhance the growth inhibition of tumor cells by lymphocytes. RNase treatment did not reduce the antiviral activity and the growth inhibition.