Submitted to: American Association of Veterinary Laboratory Diagnosticians
Publication Type: Abstract Only
Publication Acceptance Date: 10/9/2003
Publication Date: 10/9/2003
Citation: Richt, J.A., Hamir, A.N., Hoover, E.A., Bartz, J.C., Bessen, R.A. 2003. Molecular analysis of scrapie and chronic wasting disease isolates from the U.S. [Abstract]. 46th Annual Meeting of the American Association of Veterinary Laboratory Diagnosticians. p. 61. Interpretive Summary:
Technical Abstract: The transmissible spongiform encephalopathies, or prion diseases, are a group of fatal neurodegenerative diseases that include scrapie in sheep and goats, chronic wasting disease (CWD) in deer and elk, transmissible mink encephalopathy (TME) in mink and bovine spongiform encephalopathy (BSE) in cattle. The objective of this study was to evaluate molecular strain typing methods for the prion agent based on electrophoretic patterns of the major prion protein (PrP**Sc) polypeptides, as detected by antibodies directed to N-terminal and internal regions of PrP. Analysis of natural and experimental prion isolates from sheep, elk, mule deer and cattle revealed several distinct PrP**Sc polypeptide patterns. Three distinct PrP**Sc patterns were found, based on migration of the major unglycosylated PrP**Sc polypeptide. The patterns were grouped as 1) sheep with natural scrapie; 2) cattle inoculated with experimental TME and CWD agents (identified by a loss of immunoreactivity with an antibody specific for the N-terminal end of PrP**Sc); and 3) CWD isolates from elk and deer. Within the latter group, differences in the migration pattern of PrP**Sc among isolates could be found. Quantitative analysis of the ratio of the three major PrP**Sc polypeptides (sometimes referred to as the glycoform profile) was also performed, and we conclude from these preliminary studies that this methodology is not adequate for molecular identification of a prion disease from a specific host species or a particular strain of prion agent. While additional scrapie and CWD cases are needed to confirm these findings, our results suggest distinct molecular signatures of U.S. scrapie and CWD isolates as well as experimental prion diseases in cattle.