Biological studies of interferon: II. Temporal relationships of virus and interferon production by cells infected with Eastern equine encephalomyelitis and influenza viruses

Abstract

These experiments represent an attempt to evaluate the effect of endogenous interferon on the course and outcome of acute viral infections. To this end rates of virus and interferon production were compared in chick embryo (CE) and L cell cultures infected with Eastern equine encephalomyelitis (EEE) virus and in chick allantoic membranes infected with WS influenza A virus. Regardless of experimental conditions, interferon was detected only after virus multiplication had reached a peak. EEE virus could induce interferon formation in L cells in the absence of discernible cytopathology, but yields of interferon were greater in CE and L cell cultures undergoing rapid cell destruction after infection at high multiplicity. Experiments with chorioallantoic membranes revealed that the onset of interferon production coincided with disappearance of influenza hemagglutinin from the cells. Cellular levels of influenza S antigen did not appear to be significantly affected by endogenous interferon. The physical and biological properties of S antigen and interferon served to differentiate these two products of influenza-infected cells.