Two alpha-herpesvirus strains are transported differentially in the rodent visual system

Uptake and transneuronal passage of wild-type and attenuated strains of a swine alpha-herpesvirus (pseudorabies [PRV]) were examined in rat visual projections. Both strains of virus infected subpopulations of retinal ganglion cells and passed transneuronally to infect retino-recipient neurons in the forebrain. However, the location of infected forebrain neurons varied with the strain of virus. Intravitreal injection of wild-type virus produced two temporally separated waves of infection that eventually reached all known retino-recipient regions of the central neuraxis. By contrast, the attenuated strain of PRV selectively infected a functionally distinct subset of retinal ganglion cells with restricted central projections. The data indicate that projection-specific groups of ganglion cells are differentially susceptible to the two strains of virus and suggest that this sensitivity may be receptor mediated.