EFFECTS OF HERPES-SIMPLEX VIRUS TYPE-1 INFECTION ON THE PLASMA-MEMBRANE AND RELATED FUNCTIONS OF HELA S3 CELLS

In this study we evaluated modifications of various structural and fun ctional properties of the plasma membrane of HeLa S3 cells following i nfection by the lytic virus herpes simplex virus type 1 (HSV-1). Na+/K +-ATPase activity considerably decreased during the first few hours po st-infection (p.i.), whereas Na+ and K+ concentrations were not signif icantly affected until a much later period. By 8h p.i., a partial memb rane depolarization in infected cells had occurred, as indicated by a small change in the transmembrane potential. HSV infection induced a t ime-dependent lipid peroxidation of HeLa cell plasma membranes tempora lly correlated with the progressive reduction in Na+/K+-ATPase activit y. Moreover, a significant decrease of membrane fluidity appeared at a late phase of the viral replicative cycle probably representing cumul ative membrane damage. These results demonstrate that HSV-1 infection induced the production of free radicals in nonphagocytic cells. Since lipid peroxidation begins at an early stage of the virus replicative c ycle, it may be directly related to viral cytopathicity.