Herpes simplex virus infection in populations of mouse dorsal root ganglion neurons: Effects of inoculation route and virus strain

Abstract

To investigate whether herpes simplex virus type-2 (HSV-2) infection of sensory ganglion neurons is restricted to a particular neuronal class, we unilaterally inoculated either the footpad, leg muscle or sciatic nerve of mice with strains of HSV-2 that differ in virulence and examined the soma sizes of lumbar dorsal root ganglion (DRG) neurons containing viral antigen near the peak of acute infection. Each inoculation route appeared relatively selective for a different portion of the neuronal size spectrum. Footpad inoculation primarily infected the smaller population of DRG neurons, by comparison, muscle inoculation tended to spare the smallest neurons while infecting medium and larger cells. Sciatic nerve inoculation infected the entire spectrum of DRG neurons. These results indicate that HSV-2 infection is not restricted to a specific subclass of sensory neurons. With any particular inoculation route, the least virulent strain infected fewer neurons than did those of greater virulence.