Enhancement of AA-amyloid formation in mice by transthyretin amyloid fragments and polyethylene glycol

The mechanism behind amyloid formation is unknown in all types of amyloidos is. Several substances can enhance amyloid formation in animal experiments. To induce secondary systemic amyloid (AA-type amyloid) formation, we injec ted silver nitrate into mice together with either amyloid fibrils obtained from patients with familial polyneuropathy (FAP) type I or polyethylene gly col (PEG). Mice injected with silver nitrate only served as controls. Amylo id deposits were detectable at day 3 in animals injected with amyloid fibri ls and in those injected with PEG, whereas in control mice, deposits were n ot noted before day 12. Our results indicate that amyloid fibrils from FAP patients and even a non-sulfate containing polysaccharide (PEG) have the po tential to act as amyloid-enhancing factors. (C) 2000 Elsevier Science B.V. All rights reserved.