FIG 1.

PHEV entry into Neuro-2a cells occurs via the endocytic pathway. (A) Entry kinetics of PHEV. Neuro-2a cells were incubated with PHEV, and noninternalized virus particles were inactivated with citrate buffer at the indicated time points. Infectivity was calculated by an IFA using an anti-PHEV-S antibody. (B) Ultrastructural analysis of PHEV entry and assembly in Neuro-2a cells. When cells were incubated with purified PHEV virions on ice, attached virus particles were engulfed by electron-dense membrane invaginations on the cell surface (a) and internalized into large endocytic vesicles, either individually or in groups (b and c). Subsequently, they were transported along the flow of endosomal maturation for uncoating, replication, and structure synthesis (d). Progeny virions were enclosed individually within small decorated vesicles in the ER-Golgi intermediate compartments (e) and then released from the cell through an opening at the fusion site (f).