Progeny Varicella-Zoster Virus Capsids Exit the Nucleus but Never Undergo Secondary Envelopment during Autophagic Flux Inhibition by Bafilomycin A1

Girsch, James H.; Walters, Katherine; Jackson, Wallen; Grose, Charles

In addition to the newly recognized effects described in this report, BAF has been an important drug in investigations of herpesvirus entry (Table 1 ). In the HSV entry experiments, BAF was added shortly after virus inoculation (47) (Fig. 8, pathway III) . Entry of HSV-1 strain KOS into HeLa cells was inhibited by incubation in the presence of 50 nM BAF at 2 hpi, but BAF treatment did not exert a similar effect on HSV-1 entry into Vero cells. The authors concluded that successful entry of HSV-1 into some (HeLa) cells requires endocytosis and trafficking to an acidic intracellular endosome, while entry into Vero cells proceeds by fusion of the HSV-1 envelope glycoproteins to the plasma membrane. A similar mode of VZV entry by endocytosis rather than fusion has been demonstrated during VZV infection of CHO cells in the presence of 100 nM BAF (48) . Finally, our data contradict several findings in a prior report about BAF effects on the VZV infectious cycle; the report did not include any electron microscopy of their BAF-treated VZV-infected cells (49) .