To measure the genomic DNA of human herpes viruses (HHV) in the ocular fluids and to analyse the clinical relevance of HHV in uveitis.
After informed consent was obtained, a total of 111 ocular fluid ...samples (68 aqueous humour and 43 vitreous fluid samples) were collected from 100 patients with uveitis. The samples were assayed for HHV-DNA (HHV1-8) by using two different polymerase chain reaction (PCR) assays, qualitative PCR (multiplex PCR) and quantitative PCR (real-time PCR).
In all of the patients with acute retinal necrosis (n = 16) that were tested, either the HSV1 (n = 2), HSV2 (n = 3), or VZV (n = 11) genome was detected. In all patients, high copy numbers of the viral DNA were also noted, indicating the presence of viral replication. In another 10 patients with anterior uveitis with iris atrophy, the VZV genome was detected. When using multiplex PCR, EBV-DNA was detected in 19 of 111 samples (17%). However, real-time PCR analysis of EBV-DNA indicated that there were only six of the 19 samples that had significantly high copy numbers. The cytomegalovirus (CMV) genome was detected in three patients with anterior uveitis of immunocompetent patients and in one immunocompromised CMV retinitis patient. In addition, one patient with severe unilateral panuveitis had a high copy number of HHV6-DNA. There was no HHV7- or HHV8-DNA detected in any of the samples.
A qualitative multiplex PCR is useful in the screening of viral infections. However, the clinical relevance of the virus infection needs to be evaluated by quantitative real-time PCR.
Abstract
Background
Immunosuppressive agents may increase the risk of infections with human alphaherpesviruses.
Methods
We included all adult patients with moderate to severe psoriasis who initiated ...methotrexate (MTX) or biologic agents in a retrospective cohort study. An episode of alphaherpesviruses infection was defined as filling a prescription for systemic acyclovir, valacyclovir, or famciclovir. Using nationwide registries, we determined the incidence, risk factors, 180-day hospital contacts, and 30-day mortality following infection.
Results
We included 7294 patients; 4978 (68%) received MTX, and 2316 (32%) biologic agents. The incidence rates (95% confidence intervals) of alphaherpesviruses were 23 (20–27), 26 (19–35), 17 (11–27), and 6.7 (1.3–21) per 1000 person-years of follow-up in patients on MTX, tumor necrosis factor alpha (TNF-α) inhibitors, interleukin 12/23 (IL-12/23) inhibitors, and interleukin 17 (IL-17) inhibitors, respectively. Males had an unadjusted hazard ratio (HR) of 0.47 (P < .001) for alphaherpesvirus infection. Patients on IL-17 inhibitors had an adjusted HR of 0.24 (P = .048) compared to TNF-α inhibitors. Within 180 days after infection, 13%, 7.5%, and <0.5% of patients on MTX, TNF-α inhibitors, and IL-12/23 or IL-17 inhibitors, respectively, had hospital contacts, and the 30-day mortality for all groups was <0.5%.
Conclusions
The incidence and risk of alphaherpesvirus infections were comparable between patients on MTX and TNF-α inhibitors, whereas use of IL-17 inhibitors was associated with a lower risk.
1 Unité de virologie, Institut Pasteur de Madagascar, route de l'Institut Pasteur, BP 1274, Antananarivo 101, Madagascar
2 Unité de virologie, Institut Pasteur du Cambodge, 5 boulevard Monivong, BP ...983, Phnom Penh, Cambodia
3 Centro Colaborador da OMS para Referência e Pesquisa em Arbovírus, Instituto Evandro Chagas/SVS/MS, Av. Almirante Barroso, 492, 66093-020 Belém, Pará, Brazil
4 Centre Collaborateur OMS de Référence et de Recherche sur les arbovirus, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
Correspondence Jean-Marc Reynes jmreynes{at}pasteur.mg
Herpesviruses have previously been isolated from African and South-American bats. Recently, herpesviruses detected from European insectivorous bats (family Vespertilionidae) were classified molecularly as betaherpesviruses and gammaherpesviruses. In the current study, we performed PCR analyses targeting the UL30 catalytic subunit region of the DNA polymerase gene of the African and South American herpesviruses and new Malagasy and Cambodian herpesviruses isolated from bats, especially frugivorous bats from the families Pteropodidae and Phyllostomidae. The sequences obtained from the amplified products indicated that these isolates belonged to the genus Simplexvirus of the subfamily Alphaherpesvirinae . These results extend the taxonomic range of bat herpesviruses with the description of four members in the subfamily Alphaherpesvirinae . Furthermore, these data confirm and extend the geographical distribution of herpesvirus in bats to three more continents (Africa, South America and Asia) and indicate the presence of these viruses in frugivorous bats of the families Pteropodidae and Phyllostomidae.
The GenBank/EMBL/DDBJ accession numbers for the sequences generated in this study are FJ040877–FJ040891.
Published online ahead of print on 23 October 2008 as DOI 10.1099/vir.0.2008/006825-0.
Herpesviruses can be significant reptile pathogens. Herpesviral infection in a wild-caught, male spider tortoise (Pyxis arachnoides) under human care was detected during a routine wellness ...examination prior to transition between zoologic organizations. The tortoise had no clinical signs of illness. Oral swabs obtained during a physical examination as part of pre-shipment risk mitigation for infectious disease were submitted for consensus herpesvirus PCR assay and sequencing. Based on comparative sequence analysis, the novel herpesvirus identified is a member of the subfamily Alphaherpesvirinae. Studies of herpesviral phylogeny in chelonian species support branching patterns of turtle herpesviruses that closely mirror those of their hosts. The symmetry of these patterns is suggestive of close codivergence of turtle herpesviruses with their host species. The distribution of these viruses in both tortoises and emydids suggests a phylogenetic duplication event in the herpesviruses after host divergence of the Pleurodira and basal to the divergence of Americhelydia. Herpesviral infections have been documented to cause higher morbidity when introduced to aberrant host species, and significant consideration must be given to the presence of herpesviruses in the management of tortoise collections, particularly collections that include various species of testudines.
Herpesviruses uniquely express two essential nuclear egress-regulating proteins forming a heterodimeric nuclear egress complex (core NEC). These core NECs serve as hexameric lattice-structured ...platforms for capsid docking and recruit viral and cellular NEC-associated factors that jointly exert nuclear lamina as well as membrane-rearranging functions (multicomponent NEC). The regulation of nuclear egress has been profoundly analyzed for murine and human cytomegaloviruses (CMVs) on a mechanistic basis, followed by the description of core NEC crystal structures, first for HCMV, then HSV-1, PRV and EBV. Interestingly, the highly conserved structural domains of these proteins stand in contrast to a very limited sequence conservation of the key amino acids within core NEC-binding interfaces. Even more surprising, although a high functional consistency was found when regarding the basic role of NECs in nuclear egress, a clear specification was identified regarding the limited, subfamily-spanning binding properties of core NEC pairs and NEC multicomponent proteins. This review summarizes the evolving picture of the relationship between sequence coevolution, structural conservation and properties of NEC interaction, comparing HCMV to α-, β- and γ-herpesviruses. Since NECs represent substantially important elements of herpesviral replication that are considered as drug-accessible targets, their putative translational use for antiviral strategies is discussed.
As a prevalent agent in cats, feline herpesvirus 1 (FHV-1) infection contributes to feline respiratory disease and acute and chronic conjunctivitis. FHV-1 can successfully evade the host innate ...immune response and persist for the lifetime of the cat. Several mechanisms of immune evasion by human herpesviruses have been elucidated, but the mechanism of immune evasion by FHV-1 remains unknown. In this study, we screened for FHV-1 open reading frames (ORFs) responsible for inhibiting the type I interferon (IFN) pathway with an IFN-β promoter reporter and analysis of IFN-β mRNA levels in HEK 293T cells and the Crandell-Reese feline kidney (CRFK) cell line, and we identified the Ser/Thr kinase US3 as the most powerful inhibitor. Furthermore, we found that the anti-IFN activity of US3 depended on its N terminus (amino acids 1 to 75) and was independent of its kinase activity. Mechanistically, the ectopic expression of US3 selectively inhibited IFN regulatory factor 3 (IRF3) promoter activation. Furthermore, US3 bound to the IRF association domain (IAD) of IRF3 and prevented IRF3 dimerization. Finally, US3-deleted recombinant FHV-1 and US3-repaired recombinant FHV-1 (rFHV-dUS3 and rFHV-rUS3, respectively) were constructed. Compared with wild-type FHV-1 and rFHV-rUS3, infection with rFHV-dUS3 induced large amounts of IFN-β
and
More importantly, US3 deletion significantly attenuated virulence, reduced virus shedding, and blocked the invasion of trigeminal ganglia. These results indicate that FHV-1 US3 efficiently inhibits IFN induction by using a novel immune evasion mechanism and that FHV-1 US3 is a potential regulator of neurovirulence.
Despite widespread vaccination, the prevalence of FHV-1 remains high, suggesting that it can successfully evade the host innate immune response and infect cats. In this study, we screened viral proteins for inhibiting the IFN pathway and identified the Ser/Thr kinase US3 as the most powerful inhibitor. In contrast to other members of the alphaherpesviruses, FHV-1 US3 blocked the host type I IFN pathway in a kinase-independent manner and via binding to the IRF3 IAD and preventing IRF3 dimerization. More importantly, the depletion of US3 attenuated the anti-IFN activity of FHV-1 and prevented efficient viral replication
and
Also, US3 deletion significantly attenuated virulence and blocked the invasion of trigeminal ganglia. We believe that these findings not only will help us to better understand the mechanism of how FHV-1 manipulates the host IFN response but also highlight the potential role of US3 in the establishment of latent infection
.
Herpesviruses (HVs) have a wide range of hosts in the animal kingdom. The result of infection with HVs can vary from asymptomatic to fatal diseases depending on subtype, strain, and host. To date, ...little is known about HVs naturally circulating in wildlife species and the impact of these viruses on other species. In our study, we used genetic and comparative approaches to increase our understanding of circulating HVs in Canadian wildlife. Using nested polymerase chain reaction targeting a conserved region of the HV DNA polymerase gene, we analyzed material derived from wildlife of western and northern Canada collected between February 2009 and Sept 2014. For classification of new virus sequences, we compared our viral sequences with published sequences in GenBank to identify conserved residues and motifs that are unique to each subfamily, alongside phylogenetic analysis. All alphaherpesviruses shared a conserved tryptophan (W856) and tyrosine (Y880), betaherpesviruses all shared a serine (S836), and gammaherpesviruses had a conserved glutamic acid (E835). Most of our wildlife HV sequences grouped together with HVs from taxonomically related host species. From
Martes americana
, we detected previously uncharacterized alpha- and beta-herpesviruses.
Alphaherpesviruses like herpes simplex virus are large DNA viruses characterized by their ability to establish lifelong latent infection in neurons. As for all herpesviruses, alphaherpesvirus virions ...contain a protein-rich layer called "tegument" that links the DNA-containing capsid to the glycoprotein-studded membrane envelope. Tegument proteins mediate a diverse range of functions during the virus lifecycle, including modulation of the host-cell environment immediately after entry, transport of virus capsids to the nucleus during infection, and wrapping of cytoplasmic capsids with membranes (secondary envelopment) during virion assembly. Eleven tegument proteins that are conserved across alphaherpesviruses have been implicated in the formation of the tegument layer or in secondary envelopment. Tegument is assembled via a dense network of interactions between tegument proteins, with the redundancy of these interactions making it challenging to determine the precise function of any specific tegument protein. However, recent studies have made great headway in defining the interactions between tegument proteins, conserved across alphaherpesviruses, which facilitate tegument assembly and secondary envelopment. We summarize these recent advances and review what remains to be learned about the molecular interactions required to assemble mature alphaherpesvirus virions following the release of capsids from infected cell nuclei.
Herpesviruses have mainly co-evolved with their hosts for millions of years. Consequently, different related host species may have been infected by various genetically related herpesviruses. ...Illustrating this concept, several ruminant alphaherpesviruses have been shown to form a cluster of viruses closely related to bovine herpesvirus 1 (BoHV-1): namely bovine herpesvirus 5, bubaline herpesvirus 1, caprine herpesvirus 1, cervid herpesviruses 1 and 2 and elk herpesvirus 1. These viruses share common antigenic properties and the serological relationships between them can be considered as a threat to BoHV-1 eradication programmes. BoHV-1 is a herpesvirus responsible for infectious bovine rhinotracheitis, which is a disease of major economic concern. In this article, the genetic properties of these ruminant alphaherpesviruses are reviewed on a comparative basis and the issue of interspecific recombination is assessed. The pathogenesis of these infections is described with emphasis on the host range and crossing of the host species barrier. Indeed, the non bovine ruminant species susceptible to these ruminant alphaherpesviruses may be potential BoHV-1 reservoirs. The differential diagnosis of these related infections is also discussed. In addition, available epidemiological data are used to assess the potential of cross-infection in ruminant populations. A better knowledge of these ruminant alphaherpesvirus infections is essential to successfully control infectious bovine rhinotracheitis.
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