|Schmerr, Mary Jo|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/4/1996
Publication Date: N/A
Technical Abstract: Fatal neurologic disease was induced in cattle by intracerebral inoculation of brain from US sheep with scrapie but not after feeding scrapie brain. The disease induced by IC inoculation differed from BSE causing us to conclude that the U.S. scrapie does not cause BSE. Surprisingly, no mice became infected from intracerebral injections of brain, spleen or mesenteric lymph node from the affected cattle. This strengthens the conclusion that bovine scrapie differs from BSE because mice are susceptible to the BSE agent. To answer the concern that additional passages of the scrapie agent in cattle would alter characteristics of the disease to more closely resemble BSE, calves were inoculated intracerebrally with brain from the affected cattle. All calves died with neurologic disease characteristic of the first passage resulting in the conclusion that no change had occurred in the agent. Preliminary evidence gained from inoculating mice with nine U.S. isolates of scrapie indicate that as many as three types of the agent may be present in the United States. A competitive assay using labeled peptides and specific antibodies for the scrapie protein and capillary electrophoresis as the detection system has been developed for identification of the prion protein of scrapie in the brain of sheep. Work is now in progress to validate this test. An immunohistochemical test was adapted and standardized for detecting prion in the brain of animals affected with scrapie, BSE or CWD.