Adaptation of the influenza virus A2-pol 29/69 to the cells of the Chinese hamster lung (CHL) and to the cells BHK-21.

In the course of research of the possibilities of adapting the influenza virus serotype A 2-Pol 29/69 to BHK-21 and CHL cells its production was established in the investigated combinations. An indication of virus replication is an increase in infectious and haemagglutination titres within 48 h after infection and gradual increase in haemadsorption. Observation of the influence of trypsin (10 microgram/ml) indicates that trypsin increases the capability of viruses to penetrate the cells. The cytopathic effect was not observed in cells infected with influenza virus.