Abstract
Factors influencing interferon production by strains of foot-and-mouth disease virus in bovine tissue cultures were investigated. In calf thyroid cultures after low input of virus the amount of interferon produced by modified strains was regularly greater and the degree of cytopathogenic effect less than that produced by virulent strains suggesting the use of these properties as a marker for innocuity in the study of virus modification. In calf kidney cultures and in surviving cultures of bovine tongue epithelium interferon production by modified strains depended on virus multiplication. In all bovine tissue cultures increased interferon titres were noted with some modified strains after high input of virus, but with others interferon titre was low due to successful viral replication in the majority of cells. In contrast to primary thyroid cells little or no interferon was detected in passaged and cloned thyroid cells infected with virulent or modified virus. The ability of modified strains to produce higher titres of interferon than their virulent counterparts appeared to depend on qualitative differences between the strains rather than on quantitative differences in the amount of non-replicating or heat inactivated virus in the preparations.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call