Incorporation of β-amyloid protein through the bovine ileal epithelium before and after weaning: Model for orally transmitted amyloidoses


Hiroyuki Nakayama, Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
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To determine the mechanism of bovine intestinal incorporation of the pathogen, and the pathogenesis of prion protein in the early stage, cows suckling and weaning were orally given a fusion protein of Aβ-EGFP. Aβ-EGFP was incorporated through the villous columnar epithelial cells and accumulated in crypt patches in the ileum of suckling cows. The sites of the uptake and accumulation of Aβ-EGFP are very close to the peripheral nervous system; however, such uptake of Aβ-EGFP was not observed in 6-month-old post-weaning cows. The present study, therefore, suggests that the weaning period is very important for the risk of transmission.