Bovine Viral Diarrhoea-mucosal Disease Virus Research Articles

Characterisation of a New Molecule Based on Two E2 Sequences from Bovine Viral Diarrhoea-mucosal Disease Virus Fused To the Human Immunoglobulin Fc Fragment.

IntroductionProper 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).Materials and MethodsThe 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.ResultsThe 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.ConclusionThese 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.

Factors associated with the bovine viral diarrhoea (BVD) status in cattle herds in Northwest Germany

In Germany, all calves are tested for the presence of bovine viral diarrhoea/mucosal disease virus (BVDV) virus since January 1, 2011. The basis for this compulsory investigation is the BVDV Federal Regulation (BVDVV), which demands testing of calves before the age of six months and according to the new regulation of June 2016 within four weeks or before entering another stock. In 2012, a questionnaire was sent to 7250 Lower Saxony cattle farmers to identify potential factors associated with the presence of BVDV. Completed questionnaires were received from 2542 farms for further analysis. For BVD status determination of these farms, the diagnostic results of 425,911 ear notch samples of calves as part of the BVD eradication period from June 2010 to December 2013 were used.For the analysis of the completed questionnaires, a univariable analysis was performed by the chi-square or Wilcoxon test for each variable studied. In addition, a multivariable logistic model was performed. Four potential risk factors remained after a backward selection in the final logistic regression model: the dairy production compared to the suckling and other types of production, the herd size, the purchase of animals and the location in western region in comparison with the central and eastern regions. In summary, according to the results of this study, the farm with the highest probability of a BVDV infection in Lower Saxony is a large dairy farm that purchases cattle and is located in a cattle-dense region. When the complete eradication of the virus will be achieved, the results of the present study may help to conduct a risk-oriented monitoring programme.

A New Look at Viruses in Type 1 Diabetes

Type 1 diabetes results from the destruction of pancreatic beta cells. Genetic factors are believed to be a major component for the development of type 1diabetes, but the concordance rate for the development of diabetes in identical twins is only about 40%, suggesting that non-genetic factors play an important role in the expression of the disease. Viruses are one environmental factor that is implicated in the pathogenesis of type 1 diabetes. To date, 14 different viruses have been reported to be associated with the development of type 1 diabetes in humans and animal models. Viruses may be involved in the pathogenesis of type 1 diabetes in at least two distinct ways: by inducing beta cellspecific autoimmunity, with or without infection of the beta cells, (e.g. Kilham rat virus) and by cytolytic infection and destruction of the beta cells (e.g. encephalomyocarditis virus in mice). With respect to virus-mediated autoimmunity, retrovirus, reovirus, Kilham rat virus, bovine viral diarrhoea-mucosal disease virus, mumps virus, rubella virus, cytomegalovirus and Epstein-Barr virus are discussed. With respect to the destruction of beta cells by cytolytic infection, encephalomyocarditis virus, mengovirus and Coxsackie B viruses are discussed. In addition, a review of transgenic animal models for virus-induced autoimmune diabetes is included, particularly with regard to lymphocytic choriomeningitis virus, influenza viral proteins and the EpsteinBarr viral receptor. Finally, the prevention of autoimmune diabetes by infection of viruses such as lymphocytic choriomeningitis virus is discussed.

A new look at viruses in type 1 diabetes.

Type 1 diabetes (T1D) results from the destruction of pancreatic beta cells. Genetic factors are believed to be a major component for the development of T1D, but the concordance rate for the development of diabetes in identical twins is only about 40%, suggesting that nongenetic factors play an important role in the expression of the disease. Viruses are one environmental factor that is implicated in the pathogenesis of T1D. To date, 14 different viruses have been reported to be associated with the development of T1D in humans and animal models. Viruses may be involved in the pathogenesis of T1D in at least two distinct ways: by inducing beta cell-specific autoimmunity, with or without infection of the beta cells, [e.g. Kilham rat virus (KRV)] and by cytolytic infection and destruction of the beta cells (e.g. encephalomyocarditis virus in mice). With respect to virus-mediated autoimmunity, retrovirus, reovirus, KRV, bovine viral diarrhoea-mucosal disease virus, mumps virus, rubella virus, cytomegalovirus and Epstein-Barr virus (EBV) are discussed. With respect to the destruction of beta cells by cytolytic infection, encephalomyocarditis virus, mengovirus and Coxsackie B viruses are discussed. In addition, a review of transgenic animal models for virus-induced autoimmune diabetes is included, particularly with regard to lymphocytic choriomeningitis virus, influenza viral proteins and the Epstein-Barr viral receptor. Finally, the prevention of autoimmune diabetes by infection of viruses such as lymphocytic choriomeningitis virus is discussed.

Attempt to discriminate between bovine viral-diarrhoea virus strains using polymerase chain reaction.

The polymerase chain reaction (PCR) was applied to detect bovine viral-diarrhoea mucosal-disease virus (BVDV). By the use of properly prepared primers, cytopathogenic NADL, Oregon C24V, Nose, T-20 and KS86-1(+) strains, and non-cytopathogenic New York-1, No. 12, and KS86-1(-) strains could be detected. The PCR system was applied to field isolates of the viruses. All the viruses were detected by the PCR. Four patterns of the PCR amplification were recognized, and it was possible to discriminate between some strains. These results corresponded with the serotype of BVDV, as determined by the serum-neutralizing test. The BVDV gene was detectable from the leucocytes of infected cattle using the PCR method. Moreover, it was possible to detect and discriminate BVDV strains using one PCR tube that included all primer pairs.

Glycoproteins of Bovine Viral Diarrhoea-Mucosal Disease Virus in Infected Bovine Cells

Bovine cell cultures infected with bovine viral diarrhoea-mucosal disease (BVD) virus were radiolabelled with L-[35S]methionine or D-[2-3H]mannose followed by analysis of the labelled polypeptides by radioimmunoprecipitation and polyacrylamide gel electrophoresis in one and two dimensions. Six glycoproteins were detected in infected cells. Two abundant species had Mr of 48K and 56K to 58K while the less abundant species had Mr of 118K, 75K, 65K and 25K. When cells were radiolabelled with L-[35S]methionine in the presence of tunicamycin 56K to 58K migrated with apparent masses of 54K (a minor species) and 48K to 50K (the major molecular species) in PAGE. Endoglycosidase F digestion of virus-induced polypeptides caused a 4K to 6K reduction in the apparent molecular mass of 56K to 58K yielding a single 52K digested product, indicating that the heterogeneity of 56K to 58K was due to differences in the oligosaccharide moieties. Tunicamycin caused a drastic reduction in the yield of infectious virus indicating that the carbohydrate moieties serve a critical role in the infectious cycle of BVD virus.

Pathogenesis of bovine viral diarrhoea-mucosal disease (BVD-MD) virus infection in tracheal organ cultures

Bovine foetal tracheal organ cultures were infected with two strains of BVD-MD virus and observed for 35 days. The effect of the virus was assessed by observing ciliary activity in gross tissue explants and histological changes in haematoxylin and eosin stained sections. Decrease in ciliary activity and mild epithelial degeneration were first observed at 4 days post infection (p.i.), the epithelial degeneration progressing to complete destruction by day 35 p.i. Viral titres in extracellular fluids rose sharply from day 4 p.i., reached peak levels (10 5 TCID 50/ml) between 15 and 18 days p.i., and eventually declined but persisted at lower titres up to day 35 p.i., when observations were terminated.

Epizootic diarrhoea of adult cattle associated with a coronavirus-like agent

An epizootic of acute diarrhoea of adult cattle occured in Japan during the winter of 1976 to 1977. A majority of adult cattle clinically diagnosed as having the disease, showed a significant rises in antibody titres to bovine coronavirus, whereas only a smal; minority showed serological evidence of recent infection with calf rotavirus, bovine adenovirus type 7, parainfluenza virus type 3, or bovine viral diarrhoea-mucosal disease virus. A coronavirus-like agent was detected by electron-microscopy in faecal material from a cow with diarrhoea, and was subsequently isolated in primary bovine kidney cell cultures.

Detection of three polypeptides in preparations of bovine viral diarrhoea virus

Radiolabelled bovine viral diarrhoea/mucosal disease virus (BVDV) strains NADL and Oregon C24V were purified by different steps. Following immunoprecipitation, electrophoresis in SDS-polyacrylamide gels revealed three BVDV structural polypeptides with molecular weights of 57 (VP1), 44 (VP2), and 34 (VP3) kd. The two larger BVDV polypeptides VP1 and VP2 were found to be glycosylated (gp57, gp44). The data obtained on BVDV structural proteins demonstrate common features with hog cholera virus and indicate a common grouping with the family Togaviridae.