[Antiviral factor production by infected chick embryo fibroblasts]

The secretion of antiviral factor (AF) by infected cell cultures was examined. Activity of AF depended on the cell culture used. AF produced by infected chick embryo fibroblasts had maximal activity. No activity was registered in BHK-21 cells, whereas human embryo fibroblasts and cell line Vero produced a low level of activity. Actinomycin D and cycloheximide prevented the production of AF. The results indicate that VEE virus-infected chick embryo fibroblasts produce AF which may be attributed to nonspecific factors of cell defense.