Cytostatic effect of interferon-gamma and monocyte against a human carcinoma cell line

Human interferon gamma (IFN-gamma) and normal peripheral blood monocytes had appreciable anticellular activities against KB cells such that in both cases, the rate of DNA synthesis, the number and percent viability of the cells were greatly reduced by 70-85% in about 3 days post-treatment. However, neither IFN-gamma nor monocyte alone was able to totally eliminate the tumor cells. Our results suggest that IFN-gamma and monocyte could effectively prevent the growth of residual tumor cells that would have escaped destruction when only one effector element was present.