NR ATPG
AU Hijazi,N.; Elvira,G.; Gasset,M.; Gabizon,R.
TI Inoculation of SHa PrP (23-232) as ß-sheet oligomeric forms into hamsters did not induce prion disease
QU International Conference - Prion 2005: Between fundamentals and society's needs - 19.10.-21.10.2005, Congress Center Düsseldorf - Poster Session: Pathogenesis PATH-17
PT Konferenz-Poster
AB The protein only theory has been recently demonstrated by means of "de novo" generation of transmissible infectivity, when rec MoPrP(89-230) folded into ß-sheet rich oligomers with amyloid order was inoculated into transgenic mice overexpressing its mammalian counterpart MoPrP(Delta32-90). In this work we tested the possibility of disease transmission by oligomeric SHaPrP(23-232) which generate amyloid forms upon limited proteolysis of their ligand-bound complexes. Oligomeric PrP was prepared by subjecting alpha-SHaPrP(23-232) to mild acidic denaturing conditions in a crowded medium. Under this insoluble and amorphous state, PrP displayed a decreased alpha-helix content and protease sensitivity. However incubation with Cu(II) and HS/heparin, conferred to the peptides partial protease-resistance and Congo Red binding properties. All the oligomeric SHaPrP(23-232) forms (ligand-free, Cu(II)-bound, HS-bound or Cu(II)-HS complexed) bound to CHO cells with significantly higher affinity than their alpha-helical SHaPrP forms, and , as shown before for PrPsc , their binding was largely inhibited by heparin, suggesting that GAGs are required also for the binding and internalization of PrP ß-sheet oligomers into cells. Following the in-vitro experiments, oligomeric SHaPrP forms were inoculated into normal hamsters and after several months 240 days, one animal from each group was sacrificed and its brain homogenate passaged to a fresh group of animals. After addtional 300 days, none of the hamsters in both the first and the second passaged developed any disease symptomatology. Analysis of the brains discarded the appearance of PrP PK-resistant forms and alterations in PrPc such as oligomerization or resistance to normal metabolic breakdown. We conclude that PrP conformational versatility allows multiple conformations and only very specific conformations can induce prion disease.
AD Nuha Hijazi, Ruth Gabizon, Deparment of Neurology; The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital, Jerusalem Israel; Gema Elvira, Maria Gasset, Instituto Química-Física "Rocasolano" Madrid Spain
SP englisch
PO Deutschland