Mechanism of Recovery from Viral Infection in the Chick Embryo

Abstract

THE chick embryo lacks many of the mechanisms which are thought to be required for recovery from viral infections. Production of antibody and delayed hypersensitivity (as measured by ability to reject foreign tissue) do not occur in the chick embryo of any age^1,2, whereas the interferon mechanism begins to function in the embryo at about eight days and increases thereafter³. If interferon plays a major part in recovery from viral infection^4,5, then a correlation would be expected between the lethality of viral infections and absence of the interferon mechanism in young embryos. Decreasing mortality with increasing age of embryos has been reported with a number of viruses^6,7. However, the cells of these variously aged embryos yield equal amounts of virus^3,8. The present work was undertaken to determing whether the appearance of the interferon mechanism during development of the chick embryo is parallel to increased ability to recover from viral infection.