Transgenic studies primary sequence

The first evidence to suggest that the primary sequence of PrP could profoundly influence TSE species barriers came from studies utilizing the strong barrier to infection that exists between hamsters and mice. Although mice are fully susceptible to mouse scrapie, they are resistant to infection with a particular strain of hamster scrapie. Mice infected with hamster scrapie do not become clinically ill within the lifetime of the animal even though it appears that infectivity can be sequestered in these animals (Race and Chesebro, 1998). However, transgenic mice that overexpressed hamster PrP-sen were fully susceptible to hamster scrapie (Scott et al, 1989). Subsequent studies demonstrated that the hamster/mouse species barrier could be crossed even when hamster PrP-sen expression was restricted to neurons (Race et al, 1995) or astrocytes (Raeber et al, 1997), but not T-cells or hepatocytes (Raeber et al,... 

---