PrP(c) mRNA, but not PrP(Sc) is found in the salivary glands of scrapie-infected sheep.
Transmission studies in transmissible spongiform encephalopathies (TSEs) have become increasingly important due to the possible transmission of bovine spongiform encephalopathy to humans resulting in new variant Creutzfeldt-Jacob disease. The horizontal transmission of scrapie, a TSE of sheep, is poorly understood. Possible sources of horizontal transmission are the submandibular and parotid salivary glands. TSEs like natural sheep scrapie are characterized by the conversion of a normal protease sensitive prion protein, PrP(c), to an abnormal protease resistant prion protein, PrP(Sc). Since the presence of PrP(Sc) is an indicator of disease, the salivary glands of scrapie-infected sheep were examined for the presence of PrP(Sc). Although PrP(c) mRNA was detected in the salivary glands, PrP(Sc) was not found in the salivary glands of scrapie-infected sheep. These data suggest that the salivary glands are unlikely sources of horizontal transmission of natural sheep scrapie.
Herrmann
L M
LM
Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA 99164, USA. lherrmann@vetmed.wsu.edu
Baszler
T V
TV
Knowles
D P
DP
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D017931:DNA Primers; D015151:Immunoblotting; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D018621:PrPC Proteins / Q000235:genetics*; D018620:PrPSc Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012469:Salivary Glands / Q000378:metabolism*; D012608:Scrapie / Q000235:genetics*; D012756:Sheep
D017931:DNA Primers; D018621:PrPC Proteins; D018620:PrPSc Proteins; D012333:RNA, Messenger