RESUMO
The Equid alphaherpesvirus type 1 (EHV-1) infection can have devastating economic consequences in the horse industry due to large-scale outbreaks of abortions, perinatal foal mortality, and myeloencephalopathy. The present study analyzed the genome of two isolates obtained from aborted fetuses in Argentina, E/745/99 and E/1297/07. The E745/99 genome shares 98.2% sequence identity with Ab4, a reference EHV-1 strain. The E/1297/07 genome shares 99.8% identity with NY03, a recombinant strain containing part of ORF64 and part of the intergenic region from Equid alphaherpesvirus-4 (EHV-4). The E/1297/07 genome has the same breakpoints as other United States and Japanese recombinants, including NY03. The recombinant regions have varying numbers of tandem repeat sequences and different minor parental sequences (EHV-4), suggesting distinct origins of the recombinant events. These are the first complete genomes of EHV-1 from Argentina and South America available in the Databases.
Assuntos
Genoma Viral , Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Filogenia , Argentina , Herpesvirus Equídeo 1/genética , Herpesvirus Equídeo 1/isolamento & purificação , Herpesvirus Equídeo 1/classificação , Animais , Genoma Viral/genética , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Cavalos/virologia , Recombinação Genética , Doenças dos Cavalos/virologia , Fases de Leitura Aberta/genética , Sequenciamento Completo do Genoma , DNA Viral/genéticaRESUMO
The ORF 70 gene of equid alphaherpesvirus type 3 (EHV-3) encodes glycoprotein G (gG), which is conserved in the majority of alphaherpesviruses. This glycoprotein is located in the viral envelope and has the characteristic of being secreted into the culture medium after proteolytic processing. It modulates the antiviral immune response of the host by interacting with chemokines. The aim of this study was to identify and characterize EHV-3 gG. By constructing viruses with HA-tagged gG, it was possible to detect gG in lysates of infected cells, their supernatants, and purified virions. A 100-, 60-, and 17-kDa form of the protein were detected in viral particles, while a 60-kDa form was identified in supernatants of infected cells. The role of EHV-3 gG in the viral infection cycle was assessed by the construction of a gG-minus EHV-3 mutant and its gG-positive revertant. When growth characteristics in an equine dermal fibroblast cell line were compared, the plaque size and the growth kinetics of the gG-minus mutant were similar to those of the revertant virus, suggesting that EHV-3 gG does not play a role in direct cell-to-cell transmission or virus proliferation of EHV-3 in tissue culture. The identification and characterization of EHV-3 gG described here provide a solid background for further studies to assess whether this glycoprotein has a function in modulating the host immune response.
Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Herpesvirus Equídeo 3 , Animais , Cavalos , Proteínas do Envelope Viral/metabolismo , Herpesvirus Equídeo 1/genética , Herpesvirus Equídeo 3/metabolismo , Linhagem Celular , Glicoproteínas/genéticaRESUMO
A 17-y-old Rocky Mountain gelding was presented to the Virginia-Maryland Veterinary Teaching Hospital because of a 4-wk history of anorexia, weight loss, lethargy, and fever of unknown origin. Abdominal ultrasound revealed lymphadenomegaly of the abdominal and colonic lymph nodes, thickening of the wall of the large colon, and a mass associated with the large colon. The horse was euthanized given a poor prognosis. On autopsy, an ~20-cm diameter mass was found within the mesocolon between the right ventral and right dorsal colon. The mass had invaded through the colonic walls and formed a fistula between the 2 involved lumina. On histologic evaluation, the mass consisted of small numbers of large neoplastic lymphocytes, numerous small lymphocytes, and many foamy macrophages. A diagnosis of T-cell-rich, large B-cell lymphoma was made based on immunohistochemical staining for CD79a, CD3, and Iba1; concurrent infection with equid herpesvirus 5 was confirmed with in-situ hybridization (ISH). To our knowledge, neither a trans-colonic fistula resulting from alimentary lymphoma in a horse nor detection of intralesional equid herpesvirus 5 in equine alimentary lymphoma by ISH has been reported previously.
Assuntos
Herpesvirus Equídeo 1 , Doenças dos Cavalos , Linfoma Difuso de Grandes Células B , Cavalos , Animais , Masculino , Hospitais Veterinários , Hospitais de Ensino , Linfoma Difuso de Grandes Células B/veterinária , Colo/patologia , Linfócitos T , Doenças dos Cavalos/diagnósticoRESUMO
BACKGROUND: Equid herpesvirus (EHV) commonly affects horses causing neurologic and respiratory symptoms beside spontaneous abortions, meaning huge economic losses for equine industry worldwide. In foals, the virus can facilitate secondary infections by Rhodococcus equi, important in morbidity and mortality in equines. A total of five genotypes of EHV were previously described in Brazil including EHV-1, EHV-2, EHV-3, EHV-4, and EHV-5. EHV-2 genotype had only been previously described in Brazil in asymptomatic animals. We report the investigation of the dead of 11 foals in Middle-west region of Brazil showing respiratory and neurological symptoms, as well as several abortions in mares from the same farm. METHODS: Clinical and laboratory exams were performed in this case study. Lung, whole blood, serum, and plasma samples were analyzed by necroscopic and histopathologic techniques followed by molecular assays (conventional and qPCR and Sanger sequencing). RESULTS AND CONCLUSION: Laboratory exams revealed neutrophilia leukocytosis. Necroscopic and histopathologic findings were suppurative bronchopneumonia and ulcerative enteritis. Molecular assays point to the absence of the bacteria Rhodococcus equi and other viruses (including other EHV). The presence of EHV-2 DNA was confirmed by sequencing in serum sample from one foal. This is the first confirmed outbreak of EHV-2 causing disease in Brazilian horses with confirmed presence of the virus, and which highlight the important role of EHV-2 in equine respiratory disease and spontaneous abortions in equid in Brazil.
Assuntos
Aborto Espontâneo , Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Rhadinovirus , Gravidez , Feminino , Humanos , Animais , Cavalos , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/veterinária , Aborto Espontâneo/epidemiologia , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/epidemiologia , Surtos de Doenças/veterináriaRESUMO
Both pregnancy and obesity can influence significant changes in the immune system. On this basis, the present study proposes to evaluate the humoral immune response of overweight pregnant mares in response to a commercial vaccine. Thirty pregnant Crioulo mares were separated according to body condition score (BCS) into overweight (BCS≥7/9) or lean-control (BCS= 5-6/9). In each group, the animals were subdivided into vaccinated and controls. The mares were vaccinated against EHV-1 in two doses spaced 21 days apart and had their blood collected monthly, for five months, for antibody evaluation. Both vaccinated groups had an increase in specific neutralizing antibodies after the vaccine. However, after the second dose, there was no increase in antibodies in any of the groups. Vaccinated overweight and lean-control mares did not differ at any time point. Therefore, this study demonstrated that obesity does not influence the humoral immune response in pregnant Crioulo mares.(AU)
Tanto a gestação quanto a obesidade podem influenciar o desenvolvimento de alterações significativas no sistema imune, portanto, o presente estudo teve como objetivo avaliar a resposta imune humoral de éguas gestantes com sobrepeso em resposta a uma vacina comercial. Trinta éguas Crioulas gestantes foram separadas de acordo com o escore de condição corporal (ECC) em éguas com sobrepeso (ECC≥7/9) e éguas controles (ECC=5-6/9) e, ainda, em cada grupo, os animais também foram separados em vacinados e controles. As éguas foram vacinadas contra o EHV-1 em duas doses com intervalo de 21 dias, sendo realizadas coletas de sangue mensalmente durante cinco meses para avaliação de anticorpos neutralizantes. Ambos os grupos vacinados tiveram aumento de anticorpos neutralizantes específicos após a vacina, porém, após a segunda dose, não foi observado aumento de anticorpos em nenhum dos grupos. Nenhuma diferença foi observada entre éguas vacinadas com sobrepeso e as éguas controles em nenhum momento. Assim, este estudo demonstrou que a obesidade não é um fator que influencia a resposta imune humoral de éguas Crioulas gestantes.(AU)
Assuntos
Animais , Feminino , Gravidez , Vacinas/farmacologia , Imunidade Humoral/fisiologia , Cavalos/imunologia , Prenhez/fisiologia , Herpesvirus Equídeo 1/patogenicidade , Sobrepeso/veterináriaRESUMO
Clinical History: A euthanized, 14-year-old, Warmblood gelding that had participated in an equine show was presented for necropsy and diagnostic workup to the San Bernardino laboratory of the California Animal Health and Food Safety Laboratory System. The animal had a 4-day history of mildly swollen limbs and hyperthermia, and developed neurologic signs shortly before euthanasia. Necropsy Findings: The urinary bladder had multifocal to coalescing hemorrhages in the mucosa and approximately 5 ml of turbid urine with sandy sludge (Figure 1). The entire spinal cord was removed and cross-sectioned serially after fixation in 10% neutral-buffered formalin during 48h. Multifocally, in multiple sections of the cervical, thoracic, and lumbar segments, there were uni- or bilateral and asymmetrical, wedge-shaped areas of gray discoloration and hemorrhage (Figures 2-4). In addition, there were extensive hemorrhages around the nerve roots of the cauda equina. Follow-up questions: Five differential diagnoses for the gross lesions in the spinal cord (Fig. 1B-1D) Microscopic description for the lesions in the spinal cord (Fig. 2A-2D) Most likely cause based on clinical history and gross and microscopic findings.
Assuntos
Animais , Masculino , Infecções por Herpesviridae/diagnóstico , Doenças dos Cavalos/virologia , Cavalos/virologia , Herpesvirus Equídeo 1RESUMO
Equid alphaherpesvirus 1 (EHV-1) causes myeloencephalopathy in horses and occasionally in non-equid species. Although mouse models have been developed to understand EHV-1 pathogenesis, few EHV-1 strains have been identified as highly neurovirulent to mice. The aim of this study was to evaluate the pathogenesis of 2 neurovirulent EHV-1 strains in mice, and to characterize the inflammatory cells and expression of chemokines and the apoptosis marker caspase-3 in the brain of infected mice. C57BL/6J mice were inoculated intranasally with EHV-1 strains A4/72 or A9/92 and evaluated on 1, 2, and 3 days post inoculation (DPI). EHV-1-infected mice showed severe neurological signs at 3 DPI. Ultrastructural analysis revealed numerous viral nucleocapsids and fewer enveloped virions within degenerated and necrotic neurons and in the surrounding neuropil. Histologically, at 3 DPI, there was severe diffuse neuronal degeneration and liquefactive necrosis, prominent microgliosis, and perivascular cuffing composed of CD3+ cells (T cells) and Iba-1+ cells (macrophages), mainly in the olfactory bulb and ventral portions of the brain. In these areas, moderate numbers of neuroglial cells expressed CCL5 and CCL2 chemokines. Numerous neurons, including those in less affected areas, were immunolabeled for cleaved caspase-3. In conclusion, neurovirulent EHV-1 strains induced a fulminant necrotizing lymphohistiocytic meningoencephalitis in mice, with microgliosis and expression of chemokines and caspase-3. This model will be useful for understanding the mechanisms underlying the extensive neuropathology induced by these viral infections.
Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Doenças dos Roedores , Animais , Encéfalo , Modelos Animais de Doenças , Infecções por Herpesviridae/veterinária , Cavalos , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Equine herpesvirus type 1 (EHV-1) is an emerging pathogen that causes encephalomyelitis in horses and non-equid species. Several aspects of the immune response in the central nervous system (CNS), mainly regarding the role of inflammatory mediators during EHV-1 encephalitis, remain unknown. Moreover, understanding the mechanisms underlying extensive neuropathology induced by viruses would be helpful to establish therapeutic strategies. Therefore, we aimed to evaluate some aspects of the innate immune response during highly neurovirulent EHV-1 infection. C57BL/6 mice infected intranasally with A4/72 and A9/92 EHV-1 strains developed a fulminant neurological disease at 3 days post-inoculation with high viral titres in the brain. These mice developed severe encephalitis with infiltration of monocytes and CD8+ T cells to the brain. The inflammatory infiltrate followed the detection of the chemokines CCL2, CCL3, CCL4, CCL5, CXCL2, CXCL9 and CXCL-10 in the brain. Notably, the levels of CCL3, CCL4, CCL5 and CXCL9 were higher in A4/72-infected mice, which presented higher numbers of inflammatory cells within the CNS. Pro-inflammatory cytokines, such as interleukins (ILs) IL-1α, IL-1ß, IL-6, IL-12ß, and tumour necrosis factor (TNF), were also detected in the CNS, and Toll-like receptor (TLR) TLR2, TLR3 and TLR9 genes were also upregulated within the brain of EHV-1-infected mice. However, no expression of interferon-γ (IFN-γ) and IL-12α, which are important for controlling the replication of other herpesviruses, was detected in EHV-1-infected mice. The results show that the activated innate immune mechanisms could not prevent EHV-1 replication within the CNS, but most likely contributed to the extensive neuropathology. The mouse model of viral encephalitis proposed here will also be useful to study the mechanisms underlying extensive neuropathology.
Assuntos
Encéfalo/imunologia , Encefalite Viral/imunologia , Infecções por Herpesviridae/imunologia , Herpesvirus Equídeo 1/imunologia , Herpesvirus Equídeo 1/patogenicidade , Animais , Encéfalo/metabolismo , Encéfalo/virologia , Quimiocinas/genética , Quimiocinas/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite Viral/virologia , Infecções por Herpesviridae/virologia , Imunidade Inata , Leucócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Toll-Like/genética , Regulação para Cima , Carga ViralRESUMO
EHV-1 infection is responsible for huge economic losses in equines due to abortion and neonatal mortality. In this study, we describe 4 cases of abortion and neonatal deaths from pregnant mares and a she-donkey from different localities in Egypt during the period from May 2015 to October 2017. Attempts were made to isolate and identify EHV-1, in addition to compare the different pathological lesions in various tissues of the necropsied cases. EHV-1 was successfully isolated from two aborted fetuses and one dead neonatal foal from mares, beside one aborted fetus from a she-donkey. The positive cases showed cytopathic effect on embryonated chicken eggs scattered on chorioallantoic membrane. Moreover, PCR was applied for the pock lesions and revealed positive results for EHV-1. Interstitial pneumonia, bronchopneumonia and necrosis of hepatic, myocardial, microcotyledonary tissues besides disseminated thrombi were the main encountered lesions. Intranuclear inclusion bodies were demonstrated in brain, liver, placenta and pulmonary tissues. Here, we describe EHV-1 induced brain lesions represented by degenerated neurons, vascular endotheliosis with intranuclear inclusion bodies in the aborted she-donkey fetus. Lesions were more sever in the aborted fetuses from mares than the one from the she-donkey. EHV-1 antigen was detected by immunohistochemistry staining.
Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Aborto Animal , Animais , Equidae , Feminino , Feto , Infecções por Herpesviridae/veterinária , Cavalos , GravidezRESUMO
Equine alphaherpesvirus is a major pathogen that causes respiratory disorders, abortion, neurological syndromes, and perinatal mortality in horse populations worldwide. The aim of this study was to determine whether the occurrence of anti-alphaherpesvirus antibodies is correlated to reproductive abnormalities in horses in the state of Pernambuco, Brazil. The virus neutralization was carried out in 322 serological samples from unvaccinated horses from 42 farms located in 16 municipalities in the Microregion of the Vale do Ipojuca, Pernambuco, Brazil. Of these horses, 23.3% (75/322; 95% CI: 18.9-28.4%) were found to be reactive to anti-alphaherpesvirus antibodies. In addition, 61.9% (26/42) of farms had at least one reactive animal, with an inter-herd variation of 5% to 100%. With regard to reproductive rates, herpetic infection was associated with the use of biological reproductive techniques such as artificial insemination (AI) and embryo transfer (ET), which uses natural mating (p = 0.003); history of perinatal mortality (p = 0.004); birth interval greater than two years (p = 0.003); and reproductive seasonality of mares with irregular cycles in the herd (p = 0.041). This is the first report on the identification of horses reactive to anti-alphaherpesvirus antibody in the state of Pernambuco, Brazil. From the results obtained, the adoption of prophylactic measures such as vaccination is suggested in order to prevent infection in susceptible animals and to reduce the viral load excreted by animals with quiescent infection.
O alfaherpesvírus equino é um importante agente patogênico causador de distúrbios respiratórios, aborto, síndrome neurológica e mortalidade perinatal em populações de equinos em todo o mundo. O objetivo deste trabalho foi determinar a ocorrência de anticorpos anti-alfaherpesvírus e relacionar às alterações reprodutivas em equinos no estado de Pernambuco, Brasil. A vírus neutralização foi realizada em 322 amostras sorológicas de equinos não vacinados, provenientes de 42 propriedades de 16 municípios pertencentes à Microrregião do Vale do Ipojuca, Pernambuco, Brasil. Observou-se uma ocorrência de 23,3% (75/322; IC 95%:18,9-28,4%) de equinos reagentes à pesquisa de anticorpos anti-alfaherpesvírus. Além disso, 61,9% (26/42) das propriedades possuíam pelo menos um animal reagente, com variação inter-rebanho de 5 a 100%. Em relação aos índices reprodutivos, associou-se à infecção herpética a utilização de biotécnicas reprodutivas, como a inseminação artificial (IA) e a transferência de embriões (TE), com a monta natural (p = 0,003); histórico de mortalidade perinatal (p = 0,004); intervalo entre partos superior a dois anos (p = 0,003); e sazonalidade reprodutiva de éguas com ciclos irregulares no rebanho (p = 0,041). Este é o primeiro relato de detecção de equinos reagentes à pesquisa de anticorpos anti-alfaherpesvírus no estado de Pernambuco, Brasil. A partir dos resultados obtidos, sugere-se a adoção de medidas profiláticas como a vacinação, a fim de prevenir a infecção nos animais suscetíveis e reduzir a carga viral excretada nos animais com infecção quiescente.