CASP3 and infection: A time-course analysis in THP-1 cells indicates that in both wild-type HSV-1 and R3630 infected cells the cleavage of caspase-3 and PARP occurred at later time point post-infection (24 and 48 h.p.i) confirming the activation of the apoptotic pathway (Fig. 3a; lanes 11-12 and 14-15).