Intestinal uptake of amyloid ß protein through columnar epithelial cells in suckling mice
Yasuhisa Ano1, Hiroyuki Nakayama2,4, Akikazu Sakudo5, Yoriko Sawano3, Masaru Tanokura3, Shigeyoshi Itohara6 and Takashi Onodera1,4
1Department of Molecular Immunology, 2Department of Veterinary Pathology, 3Department of Food Biotechnology and 4Research Center for Food Safety, Graduate School of Agricultural and Life Sciences, the University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan,5Research Institute for Microbial Diseases, Osaka University, Yamadaoka, Suita, Osaka , Japan and 6Laboratory for Behavioral Genetics, Brain Science Institute, RIKEN, Wako, Saitama, Japan.
Offprint requests to: Professor Dr. H. Nakayama, Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan. e-mail: anakaya@mail.ecc.u-tokyo.ac.jp
Summary. The mechanism of transmission of amyloid protein, especially the dynamics in the intestine, is still largely unknown. In the present study, a fusion protein (Aß-EGFP) that combined enhanced green fluorescent protein with amyloid-ß protein (Aß) was orally administered to mice before and after weaning, and the uptake and kinetics of amyloid protein within the intestine were elucidated through histopathology. Aß-EGFP was incorporated into the cytoplasm of columnar epithelial cells, rather than M cells, at 3 h after administration and thereafter. Aß-EGFP then accumulated in the crypt, Peyer's patch, and even the spleen. However, this uptake was not observed in weaned mice. These results suggest that a specific tolerant mechanism for incorporation of Aß escaped from the digestion exists during suckling periods. This age-dependent uptake is important for estimating the risk of transmission. Histol Histopathol 24, 283-292 (2009)
Key words: Amyloid-ß protein, Amyloidoses, Columnar epithelial cells, Suckling periods, Uptake
DOI: 10.14670/HH-24.283