Deposition of transthyretin amyloid is not accelerated by the same amyloid in vivo.
Acceleration of amyloid deposition by administration of amyloid fibrils and transmissibility of disease have been reported in several types of amyloidoses. Families with a variant transthyretin (TTR V30M)-associated familial amyloidotic polyneuropathy (FAP) exhibit genetic anticipation, with TTR V30M-amyloid depositing at an earlier age in successive generations. The molecular bases of anticipation in FAP have remained to be determined. We asked if administration of TTR-amyloid fibrils (ATTR) extracted from the heart of an FAP TTR V30M patient would accelerate ATTR deposition in transgenic mice expressing the human mutant ttr gene responsible for FAP TTR V30M and indeed the administration did accelerate deposition of apolipoprotein A-II-amyloid fibrils (AApoAII), and not A TTR. Our experiments present, for the first time, evidence that the degree of inducibility of ATTR is low relative to AApoAII and we suggest that administration of ATTR may not explain the genetic anticipation which occurs in FAP.
Wei
Lan
L
Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Nakakoma, Yamanashi 409-3898, Japan.
Kawano
Hiroo
H
Fu
Xiaoying
X
Cui
Dan
D
Ito
Sadahiro
S
Yamamura
Ken-ichi
K
Ishihara
Tokuhiro
T
Tokuda
Takahiko
T
Higuchi
Keiichi
K
Maeda
Shuichiro
S
D000682:Amyloid / Q000378:metabolism*; D028227:Amyloid Neuropathies, Familial / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D006801:Humans; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008822:Mice, Transgenic; D046529:Microscopy, Electron, Transmission; D009154:Mutation / Q000235:genetics; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D011228:Prealbumin / Q000235:genetics / Q000378:metabolism*
D000682:Amyloid; D011228:Prealbumin