NR ATFR
AU Giese,A.; Weber,P.; Piening,N.; Thomzig,A.; Beekes,M.; Kretzschmar,H.A.
TI Cell-free generation of prion infectivity by serial PMCA
QU International Conference - Prion 2005: Between fundamentals and society's needs - 19.10.-21.10.2005, Congress Center Düsseldorf - Oral sessions ORAL-22
PT Konferenz-Vortrag
AB The structural conversion of cellular prion protein (PrPc) to the disease-associated misfolded isoform (PrPsc) can be modelled in vitro by protein misfolding cyclic amplification (PMCA). Using serial transmission PMCA (sPMCA) we could recently prove the autocatalytic nature of propagation of protease-resistant PrP detected by Western blot (PrPres) in vitro. Moreover, we achieved an amplification of PrPres by four orders of magnitude, which allows a clear separation of infectivity generated by the sPMCA reaction from the infectivity of the initial brain material used to seed the reaction. Wild-type hamsters challenged with PrPres obtained by sPMCA amplification showed accumulation of PrPsc in their brains and developed a neurological disease indistinguishable from the strain used to seed the sPMCA reaction. PrPres generated by PMCA was associated with approximately ten times less infectivity than an equivalent quantity of brain-derived PrPsc. However, animals challenged with sPMCA-derived PrPres coupled to nitrocellulose (NC) particles exhibited cerebral PrPsc deposition and scrapie symptoms as fast as animals inoculated with NC particles incubated in infectious scrapie brain homogenate. These findings demonstrate for the first time, that - a specific delivery on carrier particles provided - in vitro generated misfolded prion protein is as infectious as brain derived PrPsc. Thus, our findings provide pivotal evidence in favour of the prion hypothesis.
AD Armin Giese, Petra Weber, Niklas Piening, Hans Kretzschmar, Zentrum für Neuropathologie und Prionforschung, LMU München, Germany; Achim Thomzig, Michael Beekes, Robert-Koch-Institut, 2P24, Berlin, Germany
SP englisch
PO Deutschland