Role of Interferon in Replication of Virulent and Attenuated Strains of Measles Virus

Abstract

Small concentrations of actinomycin D increased the yields of both virulent and attenuated strains of measles virus in cultures of the stable simian BSC-1 cell line by as much as five- to tenfold. The edmonston virulent strain of measles virus did not induce detectable levels of interferon in these cells but interferon was induced by the schwarz vaccine (attenuated) strain of virus over a wide range of virus input. Actinomycin D suppressed the induction of interferon in BSC-1 cells. Interferon produced in BSC-1 cells by the attenuated virus was able to protect both these cells and Vero (another stable line of green monkey kidney) cells against vesicular stomatitis virus.