Location: Arthropod-Borne Animal Diseases Research
2011 Annual Report
Subobjective 1A. Assess the role of insect salivary proteins on the pathogenesis of bluetongue virus in relevant target vertebrate hosts.
Subobjective 1B. Assess the role of insect salivary proteins on the pathogenesis of vesicular stomatitis virus in relevant target vertebrate hosts.
Subobjective 1C. Identify and characterize the vertebrate host receptors for bluetongue virus.
Subobjective 1D. Assess vesicular stomatitis virus-induced physiological variations and determine their affect on vector-host selection.
Objective 2: Determine the host-range specificity of exotic bluetongue viruses.
Subobjective 2A: Determine the susceptibility of U.S livestock to exotic bluetongue virus.
Subobjective 2B: Determine the susceptibility of U.S wildlife to exotic bluetongue virus.
Genetic diagnostic assays for emerging and re-emerging insect transmitted viruses affecting livestock and wildlife were developed. This includes: BTV, epizootic hemorrhagic disease virus (EHDV), and vesicular stomatitis virus (VSV).
Membrane proteins from cattle pulmonary artery endothelial cells and Vero Maru (VM) cells were prepared and analyzed by SDS-PAGE. A binding ELISA was used to examine virus attachment to cells. An In situ fluorescent binding assay was developed for directly measuring binding of virus to mammalian cells. The utility of the assay was demonstrated by competition experiments with putative co-receptors for bluetongue virus.
An immunofluorescent detection assay was developed for in situ detection of BTV in insect cells. This assay is specific for BTV and does not detect the related EHDV. This is a novel detection assay that contributes to the development of novel control strategies.
An Interagency Reimbursable Agreement was completed between ABADRU and APHIS, NWRC for the rearing and weaning of 16 white-tailed deer.
Importation permit was received for an EU-BTV-8 isolate from the Netherlands. Virus was received at CSU for deer and sheep studies.
Two sheep were inoculated with EU-BTV-8 to produce washed blood cell inocula for subsequent studies.
Sixteen white-tailed deer fawns were reared and weaned and transferred to CSU large animal containment laboratory.
White-tailed deer susceptibility study completed. See accomplishment below.
Comparative sequence analysis between the original BTV-8 inoculum and virus isolated from infected deer is ongoing.
A Specific Cooperative Agreement has been extended between ABADRU and CSU for BTV - sheep studies at their facilities.
Tested sera from sheep infected with EU-BTV-8 for the presence of antibody by the competitive ELISA. Demonstrated a specific antibody response following infection.
The blood from sheep infected with EU-BTV-8 was analyzed using real time PCR demonstrated viremia by 3 days post inoculation.
Mecham, J.O., Mcholland, L.E. 2010. Measurement of Bluetongue Virus Binding to a Mammalian Cell Surface Receptor by an In Situ Immune Fluorescent Staining Technique. Journal of Virological Methods.
Savini, G., Afonso, A., Mellor, P., Aradaib, I., Yadin, H., Sanaa, M., Wilson, W.C., Monico, F., Domingo, M.A. 2011. Epizootic Haemorrhagic Disease. Research in Veterinary Science. 91:1-17.