Current In Vitro Models to Study Varicella Zoster Virus Latency and Reactivation.

Varicella zoster virus (VZV) is a highly prevalent human pathogen that causes varicella (chicken pox) during primary infection and establishes latency in peripheral neurons. Symptomatic reactivation often presents as zoster (shingles), but it has also been linked to life-threatening diseases such as encephalitis, vasculopathy and meningitis. Zoster may be followed by postherpetic neuralgia, neuropathic pain lasting after resolution of the rash.

2018 Colorado Alphaherpesvirus Latency Society Symposium.

Meeting Report on the 8th Annual Symposium of the Colorado Alphaherpesvirus Latency Society (CALS), held on May 16-19, 2018, in Vail, Colorado.

Interleukin-6 and type 1 interferons inhibit varicella zoster virus replication in human neurons.

Varicella zoster virus (VZV) is a neurotropic alphaherpesvirus that, following primary infection (varicella), establishes latency in sensory, autonomic, sympathetic and parasympathetic neurons, where it remains until reactivation (zoster). VZV-specific cell-mediated immune responses maintain VZV latency; thus, immunosuppressed and elderly persons are at risk of reactivation and associated neurological diseases. However, the cytokines produced by the immune system that control VZV in neurons are largely unknown.

Varicella Zoster Virus Induces Nuclear Translocation of the Neurokinin-1 Receptor, Promoting Lamellipodia Formation and Viral Spread in Spinal Astrocytes.

Background: Varicella zoster virus (VZV) can present as a myelopathy with spinal astrocyte infection. Recent studies support a role for the neurokinin-1 receptor (NK-1R) in virus infections, as well as for cytoskeletal alterations that may promote viral spread. Thus, we examined the role of NK-1R in VZV-infected primary human spinal astrocytes (HA-sps) to shed light on the pathogenesis of VZV myelopathy.

Erratum to: 2017 Colorado alphaherpesvirus latency society symposium.

On page 650, the institutional affiliation of Dr. Werner J.D.

Targeted Genome Sequencing Reveals Varicella-Zoster Virus Open Reading Frame 12 Deletion.

The neurotropic herpesvirus varicella-zoster virus (VZV) establishes a lifelong latent infection in humans following primary infection. The low abundance of VZV nucleic acids in human neurons has hindered an understanding of the mechanisms that regulate viral gene transcription during latency. To overcome this critical barrier, we optimized a targeted capture protocol to enrich VZV DNA and cDNA prior to whole-genome/transcriptome sequence analysis.

Induction of varicella zoster virus DNA replication in dissociated human trigeminal ganglia.

Varicella zoster virus (VZV), a human neurotropic alphaherpesvirus, becomes latent after primary infection and reactivates to produce zoster. To study VZV latency and reactivation, human trigeminal ganglia removed within 24 h after death were mechanically dissociated, randomly distributed into six-well tissue culture plates and incubated with reagents to inactivate nerve growth factor (NGF) or phosphoinositide 3-kinase (PI3-kinase) pathways. At 5 days, VZV DNA increased in control and PI3-kinase inhibitor-treated cultures to the same extent, but was significantly more abundant in anti-NGF-treated cultures (p = 0.

Varicella zoster virus infection of human fetal lung cells alters mitochondrial morphology.

Varicella zoster virus (VZV) is a ubiquitous alphaherpesvirus that establishes latency in ganglionic neurons throughout the neuraxis after primary infection. Here, we show that VZV infection induces a time-dependent significant change in mitochondrial morphology, an important indicator of cellular health, since mitochondria are involved in essential cellular functions. VZV immediate-early protein 63 (IE63) was detected in mitochondria-rich cellular fractions extracted from infected human fetal lung fibroblasts (HFL) by Western blotting.

Alphaherpesvirus DNA replication in dissociated human trigeminal ganglia.

Analysis of the frequency and PCR-quantifiable abundance of herpes simplex virus type 1 (HSV-1) and varicella zoster virus (VZV) DNA in multiple biological replicates of cells from dissociated randomly distributed human trigeminal ganglia (TG) of four subjects revealed an increase in both parameters and in both viruses during 5 days of culture, with no further change by 10 days. Dissociated TG provides a platform to analyze initiation of latent virus DNA replication within 5 days of culture.

Occupancy of RNA Polymerase II Phosphorylated on Serine 5 (RNAP S5P) and RNAP S2P on Varicella-Zoster Virus Genes 9, 51, and 66 Is Independent of Transcript Abundance and Polymerase Location within the Gene.

Unlabelled: Regulation of gene transcription in varicella-zoster virus (VZV), a ubiquitous human neurotropic alphaherpesvirus, requires coordinated binding of multiple host and virus proteins onto specific regions of the virus genome. Chromatin immunoprecipitation (ChIP) is widely used to determine the location of specific proteins along a genomic region. Since the size range of sheared virus DNA fragments governs the limit of accurate protein localization, particularly for compact herpesvirus genomes, we used a quantitative PCR (qPCR)-based assay to determine the efficiency of VZV DNA shearing before ChIP, after which the assay was used to determine the relationship between transcript abundance and the occupancy of phosphorylated RNA polymerase II (RNAP) on the gene promoter, body, and terminus of VZV genes 9, 51, and 66.

Antibodies produced by clonally expanded plasma cells in multiple sclerosis cerebrospinal fluid cause demyelination of spinal cord explants.

B cells are implicated in the etiology of multiple sclerosis (MS). Intrathecal IgG synthesis, cerebrospinal fluid (CSF) oligoclonal bands and lesional IgG deposition suggest a role for antibody-mediated pathology. We examined the binding of IgG1 monoclonal recombinant antibodies (rAbs) derived from MS patient CSF expanded B cell clones to central nervous system (CNS) tissue.

Interferon Gamma Prolongs Survival of Varicella-Zoster Virus-Infected Human Neurons In Vitro.

Infection of human neurons in vitro with varicella-zoster virus (VZV) at a low multiplicity of infection does not result in a cytopathic effect (CPE) within 14 days postinfection (dpi), despite production of infectious virus. We showed that by 28 dpi a CPE ultimately developed in infected neurons and that interferon gamma inhibited not only the CPE but also VZV DNA accumulation, transcription, and virus production, thereby prolonging the life of VZV-infected neurons.

Inhibition of phosphorylated-STAT1 nuclear translocation and antiviral protein expression in human brain vascular adventitial fibroblasts infected with varicella-zoster virus.

In varicella-zoster virus (VZV)-infected primary human brain vascular adventitial fibroblasts (BRAFs), levels of beta interferon (IFN-β,) STAT1, and STAT2 transcripts as well as STAT1 and STAT2 protein were decreased. IFN-α transcript levels were increased but not secreted IFN-α protein levels. Compared to IFN-α-treated control results, in VZV-infected BRAFs, phosphorylated STAT1 did not translocate to the nucleus, resulting in impaired downstream expression of interferon-inducible antiviral Mx1.

Varicella zoster virus DNA does not accumulate in infected human neurons.

Varicella zoster virus (VZV) is an exclusively human neurotropic alphaherpesvirus. It is unclear why human neurons infected in vitro with VZV at low multiplicity of infection do not exhibit a cytopathic effect (CPE) even though all VZV genes are transcribed, VZV proteins from all kinetic classes are translated and minimal infectious virus is produced. Here, we show that the lack of VZV-induced CPE correlates with the low abundance of viral DNA.

Comparison of varicella-zoster virus RNA sequences in human neurons and fibroblasts.

Varicella-zoster virus (VZV) infection causes varicella, after which the virus becomes latent in ganglionic neurons. In tissue culture, VZV-infected human neurons remain viable at 2 weeks, whereas fibroblasts develop cytopathology. Next-generation RNA sequencing was used to compare VZV transcriptomes in neurons and fibroblasts and identified only 12 differentially transcribed genes of the 70 annotated VZV open reading frames (ORFs), suggesting that defective virus transcription does not account for the lack of cell death in VZV-infected neurons in vitro.

Varicella zoster virus (VZV)-human neuron interaction.

Varicella zoster virus (VZV) is a highly neurotropic, exclusively human herpesvirus. Primary infection causes varicella (chickenpox), wherein VZV replicates in multiple organs, particularly the skin. Widespread infection in vivo is confirmed by the ability of VZV to kill tissue culture cells in vitro derived from any organ.

Arenavirus infection induces discrete cytosolic structures for RNA replication.

Arenaviruses are responsible for acute hemorrhagic fevers with high mortality and pose significant threats to public health and biodefense. These enveloped negative-sense RNA viruses replicate in the cell cytoplasm and express four proteins. To better understand how these proteins insinuate themselves into cellular processes to orchestrate productive viral replication, we have identified and characterized novel cytosolic structures involved in arenavirus replication and transcription.

Interaction and interdependent packaging of tegument protein UL11 and glycoprotein e of herpes simplex virus.

The UL11 tegument protein of herpes simplex virus plays a critical role in the secondary envelopment; however, the mechanistic details remain elusive. Here, we report a new function of UL11 in the budding process in which it directs efficient acquisition of glycoprotein E (gE) via a direct interaction. In vitro binding assays showed that the interaction required only the first 28, membrane-proximal residues of the cytoplasmic tail of gE, and the C-terminal 26 residues of UL11.

Interaction domains of the UL16 and UL21 tegument proteins of herpes simplex virus.

The UL16 protein of herpes simplex virus is capsid associated and was previously identified as a binding partner of the membrane-associated UL11 tegument protein (J. S. Loomis, R.

Myristylation and palmitylation of HSV-1 UL11 are not essential for its function.

All herpesviruses encode a homolog of the herpes simplex virus type-1 UL11 tegument protein. Deletion of UL11 disrupts virus envelopment, causes capsid accumulation within the cytoplasm, and reduces virus release. UL11 requires acylation with myristate and palmitate for membrane binding, lipid raft trafficking, and accumulation at the site of virus envelopment.

Sequences in the UL11 tegument protein of herpes simplex virus that control association with detergent-resistant membranes.

The product of the UL11 gene of HSV-1 is a small, membrane-bound tegument protein with features that are conserved among all herpesviruses. For all viruses examined, mutants lacking this protein (or its homolog) have budding defects and accumulate capsids in the cytoplasm of the infected cell. UL11 binds to the cytoplasmic faces of host membranes via N-terminal myristate and nearby palmitate moieties.

Adenovirus type 5 DNA-protein complexes from formaldehyde cross-linked cells early after infection.

We report here the properties of viral DNA-protein complexes that purify with cellular chromatin following formaldehyde cross-linking of intact cells early after infection. The cross-linked viral DNA fractionated into shear-sensitive (S) and shear- resistant (R) components that were separable by sedimentation, which allowed independent characterization. The R component had the density and sedimentation properties expected for DNA-protein complexes and contained intact viral DNA.