REACTIVATED AND LATENT VARICELLA-ZOSTER VIRUS IN HUMAN DORSAL-ROOT GANGLIA

Ganglia obtained at autopsy were examined by in situ hybridization fro m one patient with tester (also called herpes tester or shingles), two varicella-zoster virus (VZV)-seropositive patients without clinical e vidence of zoster, one VZV-seronegative child, and one fetus. Ganglia positive for VZV had a hybridization signal in both neuronal and nonne uronal satellite cells. Ganglia obtained from the fetus and from the s eronegative infant were consistently negative for VZV. Two striking ob servations were evident regarding the presence of VZV DNA in ganglia o btained from the individual with tester at the time of death. First, g anglia innervating the sites of reactivation and ganglia innervating a djacent sites yielded strongly positive signals in neurons and satelli te cells, whereas ganglia from distant sites were rarely positive, Sec ond, VZV DNA was found in both the nuclei and the cytoplasm of neurons innervating areas of tester, However, in neurons innervating tester-f ree areas, VZV DNA was found only in the nucleus of neurons and their supporting satellite cells, Immunohistochemistry with a fluorescent mo noclonal antibody to the VZV glycoprotein gpI, a late virus protein, r evealed a positive signal in the cytoplasm of ganglia with clinical ev idence of reactivation, These results illustrate that both neuronal an d satellite cells become latently infected following primary VZV infec tion, The presence of VZV DNA and gpI in the cytoplasm of neurons demo nstrates productive infection following reactivation at the site of la tency.