Binding, uptake and retrograde axonal transport of herpes virus suis in sympathetic neurons

Newborn rat dissociated sympathetic neurons were grown in a chamber culture system, where a Teflon ring sealed with silicon grease separated the axonal plexus from the corresponding nerve cell bodies. The binding of 35S-labeled herpes virus suis (HVS) to the neurites was partially inhibited by an excess of unlabeled HVS as well as by concanavalin A, indicating the presence of specific binding sites for the virus. Specific binding was a prerequisite for the subsequent uptake and retrograde transport of HVS to the nerve cell bodies. Predominantly free nucleocapsids were detected by electron microscopy in the axons at the time of retrograde transport, both in culture and in vivo, suggesting the possibility that nucleocapsids without lipid membrane and not contained in cellular membrane compartments can be transported by retrograde axonal transport.