Poliovirus-induced Cellular Injury

Protein leakage was used as a quantitative measure of poliovirus-induced cellular injury under suspended cell culture conditions. The requirements for protein leakage were studied in detail and it was established that events early in the infectious cycle which depend upon viral protein synthesis were responsible for cell damage. Extralysosomal β-glucuronidase appeared in infected cells before the onset of protein leakage and release of newly synthesized virus. Hydrocortisone treatment of infected cells resulted in only a slight delay in the release of β-glucuronidase from lysosomes and protein and virus from cells. These results suggest that events associated with poliovirus synthesis trigger the release of lysosomal hydrolases which in turn injure the plasma membrane, allowing cytoplasmic proteins and virus to leak out of the cell.