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Seroepidemiologic survey for adenovirus infection in lambs.
1993
Lehmkuhl H.D. | Cutlip R.C. | Brogden K.A.
A serologic survey was conducted to determine the prevalence and seroconversion rates for ovine adenovirus (OAV) serotypes 1-4 and bovine adenovirus (BAV) serotypes 2, 3, and 7 in sheep in Iowa and in surrounding states. For 2 consecutive years, paired serum samples were obtained from 1- to 2-month-old lambs as they entered a ram test station and, again, 2 months later. Sera were tested for adenovirus antibodies by use of a microtitration serum virus-neutralization test. At the time of entry, high prevalence of antibody (titer greater than or equal to 2) was detected to all tested adenoviruses except BAV-3. All adenoviruses were active in the ram test station both years, as indicated by greater than or equal to fourfold increase in adenovirus antibody titer (seroconversion) in some of the lambs. The prevalence and seroconversion rate for OAV-1 was 94.0 and 7.2%, respectively; for OAV-2, 98.6 and 15.1%; for OAV-3, 86.5 and 11.0%; for OAV-4, 98.4 and 13.2%; for BAV-2, 97.6 and 22.4%; for BAV-3, 11.4 and 3.8%; and for BAV-7, 81.6 and 4.5%. The results indicate that adenovirus infections were widespread in the sheep population and that the prevalence of active infection based on seroconversion rates was approximately 45%.
اظهر المزيد [+] اقل [-]Equine herpesvirus 2 in pulmonary macrophages of horses.
1995
Schlocker N. | Fellenberg R. von
In a search of viral agents in pulmonary macrophages of horses with chronic pulmonary disease, equine herpesvirus 2 was found to be unique. In 8 of 9 horses with chronic pulmonary disease, antigens of equine herpesvirus 2 were detected by indirect immunofluorescence staining of scattered foamy macrophages immediately after harvesting by bronchoalveolar lavage and fractionation on metrizamide gradients. In a healthy horse, antigens were not found. After 1 week of cultivation of bronchoalveolar lavage cells from a second group of 9 horses with chronic pulmonary disease, viral antigens were detected in 90% of the adherent pulmonary macrophages. In 2 of 3 healthy horses, viral antigens also were found in 90% of the adherent pulmonary macrophages. Antigens of equine herpesvirus 1, equine herpesvirus 4, parainfluenza virus 3, or adenovirus were not detected. Antigens of the 5 investigated viruses also were not detected in lung tissue slices from a third group of 14 horses, 4 healthy; 7 with varying degrees of bronchiolitis, 2 of which also had chronic intestitial pneumonia; 2 with eosinophilic bronchitis; and 1 with pulmonary hemorrhage. The exclusive presence of equine herpesvirus 2 in pulmonary macrophages was confirmed qualitatively by isolation of infective virus by cocultivation. In a fourth group of 12 horses with chronic pulmonary disease, infective virus could be isolated from pulmonary macrophages of 3 horses and from mixed-blood leukocytes of 5 horses. Virus isolations from 2 healthy horses were not successful from pulmonary macrophages, whereas 1 isolation was obtained from mixed-blood leukocytes. Other viruses were not detected by cocultivation.
اظهر المزيد [+] اقل [-]Characterisation of fowl adenovirus (FAdV-8b) strain concerning the geographic analysis and pathological lesions associated with inclusion body hepatitis in broiler flocks in Turkey
2020
Cizmecigil, Utku Yusuf | Umar, Sajid | Yilmaz, Aysun | Bayraktar, Erhan | Turan, Nuri | Tali, Besim | Aydin, Ozge | Tali, Hasan Emre | Yaramanoglu, Mehmetcan | Yilmaz, Semaha Gul | Kolukisa, Ahmet | Sadeyen, Jean-Remy | Munir, Iqbal | Yılmaz, Hüseyin
Fowl adenovirus can cause important diseases in chickens such as inclusion body hepatitis, hepatitis hydropericardium syndrome, and gizzard erosion and ulceration. Inclusion body hepatitis has been regularly reported from many countries. This is the first case report from Turkey, describing an outbreak of inclusion body hepatitis in broiler farms due to fowl adenovirus-8b (FAdV-8b). Broiler flocks with mortality about 10% were visited in Turkey, and necropsy was performed on dead birds. Samples were subjected to PCR assay to detect FAdV and other viral pathogens. After sequencing, phylogenetic analysis was performed and the nucleotide sequences of hexon genes were compared with the FAdV sequences data available in GenBank. Clinical signs such as anorexia, depression, ruffled feathers, huddling, and greenish diarrhoea were observed. Mortality started at the 8ᵗʰ day of age and ranged from 10% to 14%. Necropsy showed severe hepatitis, jaundice, and pancreatitis. The main necropsy findings included a pale, enlarged, haemorrhagic, and friable liver along with swollen and haemorrhagic kidneys and spleen. PCR and sequence analysis revealed the presence of fowl adenovirus serotype 8b (FAdV-E). This is the first report on characterisation and the pathological lesions associated with FAdV in broilers in Turkey. Our findings suggest that FAdV strains could be an emerging pathogen in Turkish broilers and could actively contribute to hepatitis and immunosuppression.
اظهر المزيد [+] اقل [-]Characterisation of a new molecule based on two E2 sequences from bovine viral diarrhoea-mucosal disease virus fused to the human immunoglobulin Fc fragment
2021
González Pose, Alaín | Montesino Seguí, Raquel | Maura Pérez, Rafael | Hugues Salazar, Florence | Cabezas Ávila, Ignacio | Altamirano Gómez, Claudia | Sánchez Ramos, Oliberto | Roberto Toledo, Jorge
Proper conformational arrangement of the E2 molecules of bovine viral diarrhoea-mucosal disease virus (BVD-MDV) is crucial to obtain an effective recombinant vaccine candidate against the disease. In this study, we characterised a new molecule composed of two distinct sequences of the E2 glycoprotein of BVD-MDV and the Fc fragment of human immunoglobulin (BVDE2Fc). The chimaeric protein was expressed in mammalian cell lines of different species by adenoviral transduction and purified by immobilised metal-affinity chromatography. The N-glycans were profiled by HPLC, and the BVDE2Fc immunogenicity was assessed in male mice. The antigen-antibody reactions were evaluated by ELISA. The MDBK cell line was selected from among five for the final production of BVDE2Fc. After purification to over 90%, the N-glycan profile showed neutral and complex oligosaccharides. The mouse immunisation induced a strong humoral response, which produced antibodies able to attach to conformational epitopes on E2 molecules, while the Fc fragment barely contributed to the immune response. Additionally, BVDE2Fc attached to antibodies from bovine sera positive to distinct BVD-MDV subtypes, whereas the loss of BVDE2Fc structure during the deglycosylation process considerably diminished those interactions. These results demonstrate that the structure of E2 molecules arranged in tandem and attached to an Fc fragment could represent a viable design for future vaccine candidates against BVD-MD.
اظهر المزيد [+] اقل [-]Suppression of immune responses in pigs by nonstructural protein 1 of Porcine reproductive and respiratory syndrome virus
2012
Zhou, Yefei | Bai, Juan | Li, Yufeng | Wang, Xinglong | Wang, Xianwei | Jiang, Ping
Porcine reproductive and respiratory syndrome (PRRS) is characterized by a delayed and defective adaptive immune response. The viral nonstructural protein 1 (NSP1) of the PRRS virus (PRRSV) is able to suppress the type I interferon (IFN) response in vitro. In this study, recombinant adenoviruses (rAds) expressing NSP1 (rAd-NSP1), glycoprotein 5 (GP5) (rAd-GP5), and the NSP1-GP5 fusion protein (rAd-NSP1-GP5) were constructed, and the effect of NSP1 on immune responses was investigated in pigs. Pigs inoculated with rAd-NSP1 or rAd-NSP1-GP5 had significantly lower levels of IFN-γ and higher levels of the immunosuppressive cytokine IL-10 than pigs inoculated with rAd-GP5, wild-type adenovirus, or cell culture medium alone. The antibody response to vaccination against classic swine fever virus (CSFV) was significantly decreased by inoculation of NSP1 7 d after CSFV vaccination in pigs. Thus, NSP1-mediated immune suppression may play an important role in PRRSV pathogenesis.
اظهر المزيد [+] اقل [-]Naturally acquired enteric adenovirus infection in Syrian hamsters (Mesocricetus auratus)
1990
Gibson, S.V. | Rottinghaus, A.A. | Wagner, J.E. | Stills, H.F. Jr | Stogsdill, P.L. | Kinden, D.A.
Intranuclear inclusions indicative of adenovirus infection were detected microscopically in formalin-fixed intestinal tissues from preweanling Syrian hamsters. The amphophilic intranuclear inclusion bodies were observed in ileal enterocytes from 16-to 24-day-old hamsters. Electron microscopy revealed large numbers of 72 +/- 3-nm viral particles typical of adenoviridae in enterocytic nuclei. Serum antibodies reacted with mouse adenovirus strains K87 and, to a lesser extent, FL, by indirect fluorescent antibody testing. Clinical disease was not associated with the adenoviral infections. Hamsters from 10 production colonies, including all major commercial Syrian hamster suppliers in the United States, were surveyed and all had serologic or histopathologic evidence of adenovirus infection.
اظهر المزيد [+] اقل [-]Differentiation of avian adenovirus type-II strains by restriction endonuclease fingerprinting
1989
Zhang, C. | Nagaraja, K.V.
Three serologically indistinguishable viruses from the avian adenovirus type-II splenomegaly virus of chickens, marble spleen disease virus of pheasants, and hemorrhagic enteritis virus of turkeys, were analyzed by restriction endonuclease fingerprinting. The DNA from these viruses were examined with 6 restriction endonucleases (Bgl II, EcoRI, HindIII, Hha I, Xho I, and BamHI). Markedly different DNA cleavage patterns were found in these virus isolates with all the 5 enzymes, except with BamHI, suggesting genetic differences between isolates of adenovirus type II. Restriction endonuclease analyses were found to provide a method for distinguishing genetically different, and yet serologically similar, strains of avian adenovirus type II.
اظهر المزيد [+] اقل [-]Oral vaccination of dogs fed canine adenovirus in baits
1989
Baer, G.M. | Brooks, R.C. | Foggin, C.M.
Six groups of 5 dogs each were fed dilutions of canine adenovirus-2, either as raw liquid or after insertion into cornmeal baits. By the fourth week after vaccination, 29 of the 30 dogs developed high titers of serum-neutralizing antibodies to the virus.
اظهر المزيد [+] اقل [-]A potential approach for assessing the quality of human and nonhuman adenoviral vector preparations
2020
Sayedahmed, Ekramy E. | Mittal, Suresh K.
Various types of human and nonhuman adenoviral (AdV) vectors are being used as gene delivery vectors in preclinical and clinical investigations. The objective of this study was to determine the ratio between the 2 best assays that would effectively address the variability in the titration of various AdV vectors in different cell lines and help obtain consistent results in preclinical and clinical studies using different AdV vectors. Here, we compared plaque-forming units, tissue culture infectious dose 50, focus-forming units (FFU), virus particle (VP) count, and genome copy number (GCN) of purified preparations of human AdV type C5, bovine AdV type 3, and porcine AdV type 3 to determine a correlation between infectious and noninfectious virus particles. Our results suggest that a VP:FFU or a VP:GCN ratio could accurately reflect the quality of an AdV preparation and could serve as an indicator to control batch-to-batch variability.
اظهر المزيد [+] اقل [-]Evaluation of a subunit vaccine for bovine adenovirus type 3
1992
York, I.A. | Thorsen, J.
The hexon subunit of bovine adenovirus serotype 3 (BAV-3) was purified by use of anion-exchange chromatography. A vaccine composed of the purified hexon in immune-stimulating complexes was administered and induced high titer of virus-neutralizing antibody in rabbits and calves.
اظهر المزيد [+] اقل [-]