Fecal transmission of AA amyloidosis in the cheetah contributes to high incidence of disease

作者：Beiru Zhang, Yumi Une, Xiaoying Fu, Jingmin Yan, Fengxia Ge, Junjie Yao, Jinko Sawashita, Masayuki Mori, Hiroshi Tomozawa, Fuyuki Kametani, Keiichi Higuchi · 发表于：Proceedings of the National Academy of Sciences · 年份：2008 · DOI：10.1073/pnas.0800367105 · 被引用次数：125 · 研究领域：Prion Diseases and Protein Misfolding、Trace Elements in Health、Veterinary Medicine and Surgery

AA amyloidosis is one of the principal causes of morbidity and mortality in captive cheetahs (Acinonyx jubatus), which are in danger of extinction, but little is known about the underlying mechanisms. Given the transmissible characteristics of AA amyloidosis, transmission between captive cheetahs may be a possible mechanism involved in the high incidence of AA amyloidosis. In this study of animals with AA amyloidosis, we found that cheetah feces contained AA amyloid fibrils that were different from those of the liver with regard to molecular weight and shape and had greater transmissibility. The infectious activity of fecal AA amyloid fibrils was reduced or abolished by the protein denaturants 6 M guanidine.HCl and formic acid or by AA immunodepletion. Thus, we propose that feces are a vehicle of transmission that may accelerate AA amyloidosis in captive cheetah populations. These results provide a pathogenesis for AA amyloidosis and suggest possible measures for rescuing cheetahs from extinction.