Inhibition of ornithine decarboxylase in human fibroblast cells by type I and type II interferons.

Dilution of human fibroblast GM2767 cell cultures into fresh serum-containing growth medium induces ornithine decarboxylase activity 45-fold over a six-hour interval. When the fibroblast cultures are supplemented with human fibroblast alpha-, beta-, or gamma-interferon at the time of dilution into fresh growth medium, the induction of ornithine decarboxylase is inhibited 61%, 90%, and 65%, respectively. beta-Interferon is the most effective type of interferon to inhibit induction of ornithine decarboxylase.