Studies on the lysosomes of L132 cells infected with either rhinovirus type 2 or poliovirus type 1.

Abstract

SUMMARY Samples taken from either rhinovirus- or poliovirus-infected suspensions of L132 cells at various times during the growth cycle were assayed for intra- and extracellular virus infectivity, trypan blue uptake and release of acid phosphatase from lysosomes. At similar times infected L132 cell monolayers were observed for cell rounding (virus c.p.e.). At 16 h after infection with rhinovirus 2, cells showed no change in the distribution of acid phosphatase activity but had undergone extreme cytopathogenic changes; at this time 99% of the virus was intracellular and few cells took up trypan blue. Poliovirus-infected cells showed no change in the distribution of acid phosphatase at 6 h after infection when cytopathogenic changes were extreme, but 2 h later when cells began to take up trypan blue and release virus, acid phosphatase was released from the lysosomes. It is suggested that lysosomal enzymes have no role in the induction of virus c.p.e. but are involved at a later stage of degeneration of the cell.