Recent studies on the properties of the infectious molecules of BSE and sheep scrapie and means of infection

Prion proteins (PI-PC) ar-e normal constituents of the membranes of nerve cells and many other cell types. They al e active as a superoxide-dismutase and in signal transmission. Following a change in structure they are transformed to infectious prion proteins (PI-PSC) that transform PI-PC to PI PSC. Th, PrPSC form of the protein is associated with BSE and scrapie infection. II? sheep some prion genes for-m instable PI PC molecules. In flocks affected by natural sheep scrapie, in lambs with valine at codon 136, arginine at codon 154 and glutamine at 171 of the PI-P gene PrPSC was detected at 2 months of age in Peyer's patches and at 3 months in all lymphatic tissue of the gastrointestinal tr-act. PrPSC was detected in the medulla oblongata at 9 months. In BSE and sheep scrapie similar glycotypes of PI PSC al e active. Feeding of PrPSC infected material to pigs and chickens did not result in clinical disease.