Oncornavirus particles in neurons of guinea pig trigeminal ganglion

Virus-like particles morphologically similar to oncornaviruses were observed in trigeminal ganglion neurons of two normal, random-bred, adult Hartley guinea pigs. Only a few neurons showed virus particles, but the particles were numerous in the cells in which they were present. Extracellular virus particles were not observed. Similar oncornavirus particles were observed in trigeminal ganglion explant cultures derived from normal guinea pigs after treatment with bromodeoxyuridine. Both intracellular and extracellular particles were frequently observed in and around supporting cells. Intracytoplasmic oncornavirus-like particles were occasionally observed within neurons. These results support consideration that trigeminal ganglion and other sensory ganglion neurons may be primary sites for latent oncornavirus infection of the nervous system.