Experimental infection of goats at different stages of pregnancy with caprine herpesvirus 1

In Vitro Activity of Ozone/Oxygen Gaseous Mixture against a Caprine Herpesvirus Type 1 Strain Isolated from a Goat with Vaginitis

Alphaherpesviruses cause genital lesions and reproductive failure in both humans and animals. Their control is mainly based on prevention using hygienic prophylactic measures due to the absence of vaccines and limitations of antiviral drug therapy. Ozone is an oxidating gas showing a strong microbicidal activity on bacteria, fungi, viruses, and protozoa. The present study assessed the in vitro virucidal and antiviral activity of ozone against caprine herpesvirus type 1 (CpHV-1). The virucidal activity of a gaseous mixture containing O₃ at 20 and 50 μg/mL was assessed against the virus at different contact times (30 s, 60 s, 90 s, 120 s, 180 s, and 300 s). Antiviral activity of a gaseous mixture containing O₃ at 20 and 50 μg/mL was evaluated against the virus after 30 s and 60 s. Ozone displayed significant virucidal activity when used at all the tested concentrations whilst significant antiviral activity was observed using ozone at 50 μg/mL. The gaseous mixture, tested in the present study, showed virucidal and antiviral activity against CpHV-1 in a dose- and time contact-dependent fashion. Ozone therapy could be evaluated in vivo for the treatment of CpHV-1-induced genital lesions in goats using topical applications.

Transcriptome and Proteomic Analysis Reveals Up-Regulation of Innate Immunity-Related Genes Expression in Caprine Herpesvirus 1 Infected Madin Darby Bovine Kidney Cells

Caprine herpesvirus 1 (CpHV-1) is a member of the alpha subfamily of herpesviruses, which is responsible for genital lesions and latent infections in goat populations worldwide. In this study, for the first time, the transcriptome and proteomics of CpHV-1 infected Madin Darby bovine kidney (MDBK) cells were explored using RNA-Sequencing (RNA-Seq) and isobaric tags for relative and absolute quantitation-liquid chromatography tandem mass spectrometry (iTRAQ-LC-MS/MS) technology, respectively. RNA-Seq analysis revealed 81 up-regulated and 19 down-regulated differentially expressed genes (DEGs) between infected and mock-infected MDBK cells. Bioinformatics analysis revealed that most of these DEGs were mainly involved in the innate immune response, especially the interferon stimulated genes (ISGs). Gene Ontology (GO) enrichment analysis results indicated that the identified DEGs were significantly mainly enriched for response to virus, defense response to virus, response to biotic stimulus and regulation of innate immune response. Viral carcinogenesis, the RIG-I-like receptor signaling pathway, the cytosolic DNA-sensing pathway and pathways associated with several viral infections were found to be significantly enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database. Eleven selected DEGs (Mx1, RSAD2, IFIT1, IFIT2, IFIT5, IFIH1, IFITM3, IRF7, IRF9, OAS1X and OAS1Y) associated with immune responses were selected, and they exhibited a concordant direction both in RNA-Seq and quantitative real-time RT-PCR analysis. Proteomic analysis also showed significant up-regulation of innate immunity-related proteins. GO analysis showed that the differentially expressed proteins were mostly enriched in defense response and response to virus, and the pathways associated with viral infection were enriched under KEGG analysis. Protein-protein interaction network analysis indicated most of the DEGs related to innate immune responses, as DDX58(RIG-I), IFIH1(MDA5), IRF7, Mx1, RSAD2, OAS1 and IFIT1, were located in the core of the network and highly connected with other DGEs. Our findings support the notion that CpHV-1 infection induced the transcription and protein expression alterations of a series of genes related to host innate immune response, which helps to elucidate the resistance of host cells to viral infection and to clarify the pathogenesis of CpHV-1.

Epidemiological investigation and genomic characterization of Caprine herpesvirus 1 from goats in China

Caprine herpesvirus 1 (CpHV-1) is a member of the alpha subfamily of herpersviruses, and is responsible for genital lesions and latent infections in goat population worldwide. Here, we describe goats suffered severe respiratory diseases caused by alphaherpesvirus during 2013 to 2014 in Jiangsu province of China. CpHV-1 was detected out by PCR with a prevalence of 21.1% (40/190), among which three novel CpHV-1 strains were firstly identified and isolated in China. Phylogenetic analysis of glycoprotein B (gB) gene revealed that these new viruses were closely clustered with CpHV-1 strain E/CH. The isolate JSHA1405 was further studied by transmission electron microscopy, and displayed typical herpesvirus morphology. Then, for the first time, complete viral genome of JSHA1405 was sequenced by Illumina Hiseq and third-generation sequencing technology. The viral genome is 134,617 bp in length and the genome characteristics were deeply analyzed. 69 open reading frames were predicted and annotated, which was less than that of BoHV-1. Phylogenetic analysis of the complete genome revealed that JSHA1405 was classified into the same branch with previous CpHV-1 strains as well. Moreover, the pathogenicity test is further evidence that JSHA1405 strain induced obvious symptoms of high fever and nasal discharge in infected goats, consistent with clinical manifestations. This is the first report about isolation and identification of CpHV-1 in China and the first characterization of CpHV-1 genome structure. The research also provides a basis for understanding the characteristics, viral genome and pathogenicity of the virus.

Antigenic relationships between Caprine alphaherpesvirus 1 (CpHV-1) and Bovine alphaherpesvirus 1 (BoHV-1) and experimental CpHV-1 infection of kids and calves

Caprine alphaherpesvirus 1 (CpHV-1) is a worldwide pathogen of goats and is closely related to Bovine alphaherpevirus 1 (BoHV-1). We herein studied the antigenic relationships of CpHV-1 with BoHV-1 and investigated the pathogenesis of CpHV-1 in kids and calves. Monoclonal antibody reactivity revealed that CpHV-1 and BoHV-1 share immunogenic epitopes in the major envelope glycoproteins gB, gC and gD. The antigenic relationship was further demonstrated by virus-neutralizing assays, in which CpHV-1 and BoHV-1 antisera presented varied degrees of cross-neutralization against the respective heterologous viruses. Although cross-neutralization was observed between both viruses and the heterologous antisera, BoHV-1 antisera neutralized CpHV-1 with higher efficiency than CpHV-1 antisera neutralized BoHV-1. Hence, the antigenic cross-reactivity between CpHV-1 and BoHV-1 should be considered upon serologic testing of goats and cattle in regions where the two viruses co-circulate. Intranasal (IN) inoculation of CpHV-1 (WI13-46 isolate) in seven seronegative kids resulted in efficient viral replication in the respiratory tract. Additionally, mild to moderate systemic and respiratory signs were observed, including apathy, hyperthermia, nasal discharge and respiratory distress. Dexamethasone administration to the inoculated kids between days 36 and 40 pi did not result in virus shedding in nasal secretions. However, latent infection had been established, as evidenced by the detection of CpHV-1 DNA in trigeminal ganglia and olfactory bulbs of kids euthanized at day 67 pi. Contrasting with the outcome of infection in kids, IN inoculation of CpHV-1 in calves did not result in productive infection as no virus replication or shedding were detected, and the animals did not develop clinical signs nor seroconverted. The animal experiments demonstrated that CpHV-1 was able to produce respiratory disease in kids, but did not replicate to detectable levels in calves.

A cross-sectional study to identify a set of risk factors for caprine herpesvirus 1 infection

BACKGROUND

Caprine herpesvirus 1 (CpHV-1) causes neonatal mortality and reproductive failure in goats. Despite its impact on herd reproductive performance, few studies have investigated the risk factors associated with CpHV-1 infection. The aim of this cross-sectional study was to identify potential herd- and host-level risk factors associated with CpHV-1 prevalence in a goat population with heterogeneous seropositivity for CpHV-1.

RESULTS

Blood samples and individual data from 4542 goats were collected from 255 herds in Piedmont, Italy. Enzyme-linked immunosorbent assay (ELISA) and serum neutralization tests were carried out to detect antibodies against CpHV-1. A mixed-effects model was applied to identify any statistical association between CpHV-1 seropositivity and a set of putative host-level and herd-level risk factors. A total of 630 samples tested were found positive by ELISA (prevalence = 13.9%; 95% confidence interval (CI) 12.9-14.9). Of the 255 tested herds, 85 were classified as positive for the presence of at least one gB-positive animal (herd prevalence 33.3%, 95% CI 27.5-39.2), with a within-herd prevalence between 0.7 and 100% (Q1 = 17.6%; median = 32.3%; Q3 = 50%) (Q = quartiles). The prevalence ratios showed a statistical association with the following risk factors: breeds other than Saanen, older age, larger herd size, meat and extensive herds, and co-existence of CAEV-infected animals.

CONCLUSIONS

Results from this cross sectional study may help to elucidate the natural history of the infection and inform targeted strategies to control a disease with a potentially important impact on animal health and goat farming economy.

Abortion in goats by Caprine alphaherpesvirus 1 in Spain

An abortion outbreak occurred in a goat herd of Murciano-Granadina breed in Almeria Region in Spain where 80 pregnant females aborted. All bacteriological and parasitological examinations resulted negative, whereas virological investigations and real-time PCR assay showed the presence of Caprine alphaherpesvirus 1 DNA in the pathological specimens from aborted foetuses. Nucleotide sequence analysis revealed that the DNA was highly close related to the Swiss strain E-CH (99.7%) and a little less extent to the Italian BA.1 strain (99.4%). Histopathological examination revealed multifocal, well-circumscribed, 50- to 200-μm-diameter foci of coagulative necrosis in the liver, lungs and kidneys of three foetuses. In the periphery of the necrosis, there were frequently epithelial cells with the chromatin emarginated by large, round, amphophilic intranuclear viral inclusion bodies. The source of the infection in the herd could not clearly find out even some hypothesis were formulated. This seems to be the first report of an abortion outbreak due to Caprine alphaherpesvirus 1 in a goat herd in Spain.

First Description of Infection of Caprine Herpesvirus 1 (CpHV-1) in Goats in Mainland France

The purpose of this study was to investigate the epidemiological situation of the caprine herpesvirus 1 (CpHV-1) infection in nine districts in mainland France, mostly in the south, near Italy or Spain, where high seroprevalence has been observed. Two more central areas were also included in the study. The serosurvey was carried out in 9564 goats (275 herds) using bovine herpesvirus 1 (BoHV-1) glycoprotein B and E ELISAs. To confirm the presence of specific CpHV-1 antibodies, some of the samples were tested in neutralization assay. Results demonstrate, for the first time, CpHV-1 infection in goat herds on the French mainland. The analysis found cases of alphaherpesviruses infection in each district studied, with different levels of seroprevalence observed within each district (ranging from 0.2% to 31.56% at an individual level and from 9% to 46.2% for herd seroprevalence). Moreover, in the Alpes-Maritimes district, the seroprevalence seemed to be higher in older goats (79.45% of animals 6 years old or more) than in younger animals (40.99% of one-year-olds). This result suggests frequent virus re-excretion and circulation in herds. Results analysis also shows that the seroprevalence was higher when the herd size increased. In addition, the first French CpHV-1 strain was isolated from nasal swabs taken on an infected goat. The data reported herein demonstrate that CpHV-1 circulates in mainland France, which should henceforth be taken into consideration in cases of unexplained abortion in goats.

Clinical protection of goats against CpHV-1 induced genital disease with a BoHV-4-based vector expressing CpHV-1 gD

Caprine herpesvirus type 1 (CpHV-1) is an alphaherpesvirus causing genital disease leading to abortion in adult pregnant goats and a systemic disease with high morbility and mortality in kids. Further, Caprine herpesvirus 1 infection represents a valuable large animal model for human herpesvirus induced genital disease, exploitable for pathogenic studies, new vaccines and antiviral molecules testing. Here, the bovine herpesvirus 4 (BoHV-4) based vector derived from an apathogenic isolate of BoHV-4 and expressing the immunodominant CpHV-1 glycoprotein D (BoHV-4-A-gD(cp)gD(106)ΔTK) was constructed and its ability to protect goats against CpHV-1 induced genital disease evaluated. The subcutaneous route of recombinant BoHV-4 administration was first tested in vivo/ex vivo by in vivo image analysis and in vitro by goat skin primary cultures preparation and transduction. Next, an exploratory immunization and safety study in goats was performed with two recombinant BoHV4, BoHV-4-A-gD(cp)gD(106)ΔTK or BoHV-4-CMV-IgK-gE2gD-TM. In both cases no clinical signs were evident but a good titer of serum neutralizing antibodies was produced in all inoculated animals. When a challenge experiment was performed in a new group of animals using a highly pathogenic dose of CpHV-1, all the vaccinated goats with BoHV-4-A-gD(cp)gD(106)ΔTK were protected toward CpHV-1 induced genital disease respect to the unvaccinated control which showed typical vaginal lesions with a high grade of clinical score as well as a long lasting viral shedding. In summary, the data acquired in the present study validate BoHV-4-based vector as a safe and effective viral vector for goat vaccination against CpHV-1 induced genital disease and pave the way for further applications.

Analysis of apoptosis induced by Caprine Herpesvirus 1 in vitro

It is known that Caprine Herpesvirus 1 (CpHV-1) causes apoptosis in mitogen-stimulated as well as not stimulated caprine peripheral blood mononuclear cells (PBMC). Initial experiments in Madin Darby bovine kidney (MDBK) cells revealed that CpHV-1 infection induced apoptotic features like chromatin condensation and DNA laddering. Thus, to characterize in more detail this apoptotic process, activation of caspase-8, -9 and -3 in MDBK cells CpHV-1 infected was investigated and demonstrated. In addition, CpHV-1 infection resulted in disruption of mitochondrial membrane potential, cytochrome c release and alterations in the pro- and anti-apoptotic proteins of Bcl-2 family. Proteolytic cleavage of poly(ADP-ribose) polymerases (PARP), confirming the activation of downstream caspases, was also observed. Our data indicated that a "cross-talk" between the death-receptor (extrinsic) pathway and the mitochondrial (intrinsic) pathway occurred in CpHV-1-induced apoptosis in vitro.

Serologic and reproductive findings after a herpesvirus-1 abortion storm in goats

CASE DESCRIPTION

An abortion storm occurred in a goat herd, resulting in 75 aborted kids and 1 neonatal death from December 2004 to February 2005.

CLINICAL FINDINGS

Aborted fetuses ranged from being premature to past term. Laboratory findings in 4 of 5 aborted fetuses were consistent with herpesvirus abortion. A virus that yielded positive results with a fluorescent antibody test for bovine herpesvirus-1 was isolated and identified as caprine herpesvirus-1 (CpHV-1) via DNA sequence analysis.

TREATMENT AND OUTCOME

Many does that aborted were rebred for kidding in late summer. Most of the young wethers born in 2005 were sold; however, all of the young does were kept for breeding in fall. In November 2005, all 241 goats in the herd were tested for antibodies against CpHV-1 to identify goats that had seroconverted during the outbreak. No complications attributable to CpHV-1 were identified during kidding in 2006.

CLINICAL RELEVANCE

On the basis of serologic findings, infection with CpHV-1 was not associated with reduced reproductive success in the subsequent breeding.

Intravaginal administration of an inactivated vaccine prevents lesions induced by caprine herpesvirus-1 in goats

To evaluate the efficacy of mucosal vaccination with a beta-propiolactone inactivated caprine herpesvirus-1 (CpHV-1) vaccine, goats received vaginal administrations of two 7-day cycles at 2 weeks intervals. Seven days after the end of the second cycle, goats were challenged intravaginally with 4 ml of virulent BA.1 strain of CpHV-1. Vaccinated goats shed challenge virus for 8 days but, in comparison with control unvaccinated-challenged goats, were significantly protected from the classical clinical signs of genital lesions. Even without adjuvants, prolonged mucosal vaccination induced production of secretory IgA and provided significant clinical protection.

Analysis of antibody response in goats to caprine herpesvirus 1

Serum samples of goats experiencing natural and experimental infections and/or reactivation of caprine herpesvirus 1 (CpHV.1) were analysed with neutralization and Western blotting (WB) tests. WB immunological patterns resulted differently and related to neutralizing titers. In serum samples having neutralizing titer 1:2-1:4, antibodies to two proteins of Mw of 150 and 34 kDa were present. Antibodies against several proteins, two of those being characterized by monoclonal antibodies as gB and gC, were visualized by WB in sera having titer > or = 1:8. The neutralizing antibody titers and the pattern of antibody reactivity were hypothesized to modulate the reactivation and re-excretion process of CpHV.1.