[Optimal conditions for demonstrating the antimitotic action of interferon]

The effect of human leukocyte interferon (HLI) on three human cell cultures of different origin was studied. HLI inhibited the mitotic activity (MA) of human ovary carcinoma cell culture and to a lower extent that of a diploid cell culture. At the same time HLI preparation exerted a nonspecific stimulating effect on MA of the primary human embryo cell culture. The optimal conditions for the determination of the antimitotic effect of interferon on cells of tumor origin include: a seed dose of 5 X 10(4) cells/ml, addition of interferon to the culture 24 hours after cell seeding; the maximum effect of interferon is observed at 24 hours after addition to the culture.