Kathy
Well-known member
For those of you interested in some reading, check out a new "letter" [report] from the Rocky Mountain Lab researchers called:
"The most infectious prion protein particles"
Jay R. Silveira, Gregory J. Raymond, Andrew G. Hughson, Richard E. Race, Valerie L. Sim, Stanley F. Hayes, and Byron Caughey
This throws a big wrench in the "infectious" theory. How come only prion aggregates of a "specific size variant" are capable of initiating further PrPC mutation?
Another quote from the summary discussion which is suggesting that other factors make up the content of the aggregates, which have not been identified yet (at least not by mainstream infectioun promotors):
"The most infectious prion protein particles"
Jay R. Silveira, Gregory J. Raymond, Andrew G. Hughson, Richard E. Race, Valerie L. Sim, Stanley F. Hayes, and Byron Caughey
Abstract
Neurodegenerative diseases such as Alzheimer's, Parkinson's and the transmissible spongiform encephalopathies (TSEs) are characterized by abnormal protein deposits, often with large amyloid fibrils. However, questions have arisen as to whether such fibrils or smaller subfibrillar oligomers are the prime causes of disease1, 2. Abnormal deposits in TSEs are rich in PrPres, a protease-resistant form of the PrP protein with the ability to convert the normal, protease-sensitive form of the protein (PrPsen) into PrPres (ref. 3). TSEs can be transmitted between organisms by an enigmatic agent (prion) that contains PrPres (refs 4 and 5). To evaluate systematically the relationship between infectivity, converting activity and the size of various PrPres-containing aggregates, PrPres was partially disaggregated, fractionated by size and analysed by light scattering and non-denaturing gel electrophoresis. Our analyses revealed that with respect to PrP content, infectivity and converting activity peaked markedly in 17−27-nm (300−600 kDa) particles, whereas these activities were substantially lower in large fibrils and virtually absent in oligomers of 5 PrP molecules. These results suggest that non-fibrillar particles, with masses equivalent to 14−28 PrP molecules, are the most efficient initiators of TSE disease.
This throws a big wrench in the "infectious" theory. How come only prion aggregates of a "specific size variant" are capable of initiating further PrPC mutation?
Another quote from the summary discussion which is suggesting that other factors make up the content of the aggregates, which have not been identified yet (at least not by mainstream infectioun promotors):
PrP content of PrP-res aggregates
Based on protein assays and ultra-microbalance measurements, 47±9% of the vacuum-dried weight of the washed, unfractionated SUS-treated PrP-res particles was protein (data not shown), and, according to semi-quantitative western blots (data not shown), >87% of the protein was PrP. Adjusting for the glycan and glycophosphatidylinositol content (~25%) of PK-treated PrP molecules, we estimate that at least 54% of the mass was attributable to PrP molecules