|WEST GREENLEE, M - Iowa State University|
Submitted to: American College of Veterinary Pathologists Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/15/2012
Publication Date: 12/1/2012
Citation: Greenlee, J.J., Smith, J.D., Vrentas, C.E., West Greenlee, M.H., Nicholson, E.M. 2012. Comparative aspects of bovine spongiform encephalopathy isolates found in the U.S. American College of Veterinary Pathologists 63rd Annual Meeting. Paper No. E-16.
Technical Abstract: Bovine spongiform encephalopathy (BSE) can be subdivided into at least three groups: classical, H-type, and L-type. The latter 2 designations are based on higher or lower apparent molecular mass profiles of the unglycosylated PrP**Sc band in a western blot and are collectively referred to as atypical BSE. The majority of cases of BSE worldwide have been ascribed to the classical form of the disease that is feedborne and transmissible to humans in the form of new variant Creutzfeldt-Jakob disease. Most cases of atypical BSE are thought to arise spontaneously, but one case of H-type BSE was associated with a heritable amino acid substitution in the prion protein gene (prnp) called E211K. The purpose of this work is to compare the features of classical, L-type, H-type, and hereditary (E211K) H-type BSE including clinical signs, antemortem test results, histopathology, and tissue distribution of PrP**Sc by western blot (WB) and immunohistochemistry (IHC) after intracranial inoculation. The fastest incubation occurred in an E211K calf inoculate with E211K H-type BSE (9.8 months) The longest incubation times occur in wild-type cattle inoculated with classical BSE (currently 27 months). Incubation times for H and L-type BSE were intermediate with an average of approximately 16 months. All forms of BSE were differentiable by western blot, however, E211K H-type BSE could only be differentiated from H-type BSE of wild type cattle using samples derived from cerebellum. When analysis is limited to the brainstem, it is difficult to differentiate isolates based on immunohistochemistry and distribution of spongiform change.