Infected peripheral blood mononuclear cells transmit latent varicella zoster virus infection to the guinea pig enteric nervous system

Abstract

Latent wild-type (WT) and vaccine (vOka) varicella-zoster virus (VZV) are found in the human enteric nervous system (ENS). VZV also infects guinea pig enteric neurons in vitro, establishes latency and can be reactivated. We therefore determined whether lymphocytes infected in vitro with VZV secrete infectious virions and can transfer infection in vivo to the ENS of recipient guinea pigs. T lymphocytes (CD3-immunoreactive) were preferentially infected following co-culture of guinea pig or human peripheral blood mononuclear cells with VZV-infected HELF. VZV proliferated in the infected T cells and expressed immediate early and late VZV genes. Electron microscopy confirmed that VZV-infected T cells produced encapsulated virions. Extracellular virus, however, was pleomorphic, suggesting degradation occurred prior to release, which was confirmed by the failure of VZV-infected T cells to secrete infectious virions. Intravenous injection of WT- or vOka-infected PBMCs, nevertheless, transmitted VZV to recipient animals (guinea pig > human lymphocytes). Two days post-inoculation, lung and liver, but not gut, contained DNA and transcripts encoding ORFs 4, 40, 66 and 67. Twenty-eight days after infection, gut contained DNA and transcripts encoding ORFs 4 and 66 but neither DNA nor transcripts could any longer be found in lung or liver. In situ hybridization revealed VZV DNA in enteric neurons, which also expressed ORF63p (but not ORF68p) immunoreactivity. Observations suggest that VZV infects T cells, which can transfer VZV to and establish latency in enteric neurons in vivo. Guinea pigs may be useful for studies of VZV pathogenesis in the ENS.

Varicella zoster virus infection

“…However, surgery and the disorder that necessitated it are undoubtedly stressful; thus, these transcripts could reflect stress-induced gene expression rather than latency-associated transcription. Interestingly, the same genes ( ORF4, ORF21, ORF29 , ORF62 , ORF63 and ORF66 ) are expressed during latency in guinea pig dorsal root ganglia and enteric neurons 39,45–47 that were obtained without stress to the animals or post-mortem delay.…”

“…Moreover, when vOka is injected at a single location, it can establish latency not only in ganglia that innervate the injection site, but also bilaterally and at multiple levels of the nervous system 37 . Experimentally, viral DNA has been found in dorsal root ganglia days before a rash occurs in monkeys infected with simian varicella virus 38 , and VZV becomes latent in dorsal root ganglia and enteric neurons after intravenous injection of guinea pigs with VZV-infected lymphocytes 39 . However, it is unclear how VZV is transferred from infected lymphocytes to neurons, and the mechanism by which neurons become latently infected is also unclear.…”

Bioengineering functional human sphincteric and non-sphincteric gastrointestinal smooth muscle constructs

“…Sphincteric smooth muscle cells were obtained from the pyloric sphincter and SI smooth muscle cells were consistently obtained from the duodenum. SMCs were isolated from human GI tissues as described previously [40, 41]. Briefly, pylorus and SI tissues were removed by sharp dissections and manually cleaned by removing fat and mucosa with a surgical blade.…”

Varicella zoster virus infection

“…However, surgery and the disorder that necessitated it are undoubtedly stressful; thus, these transcripts could reflect stress-induced gene expression rather than latency-associated transcription. Interestingly, the same genes (ORF4, ORF21, ORF29, ORF62, ORF63 and ORF66) are expressed during latency in guinea pig dorsal root ganglia and enteric neurons 39,[45][46][47] that were obtained without stress to the animals or post-mortem delay.…”

“…Neuronal pigments, however, are present in controls in which primary antibodies are omitted as well as in immunostained sections allowing pigment and reaction product to be distinguished 37,53 . Furthermore, cytoplasmic immunostaining of latencyassociated proteins has been observed in neurons of patients who were determined to have blood type B 39,53 . Future studies are needed to resolve controversies of VZV transcription and translation during latency.…”