Selection of distinct strain phenotypes in mice infected by ovine natural scrapie isolates similar to CH1641 experimental scrapie.

A few cases of transmissible spongiform encephalopathies in sheep have been described in France in which the protease-resistant prion protein (PrP(res)) exhibited some features in Western blot of experimental bovine spongiform encephalopathy in sheep. Their molecular characteristics were indistinguishable from those produced in the CH1641 experimental scrapie isolate. Four of these CH1641-like isolates were inoculated intracerebrally into wild-type C57Bl/6 mice.

Prion-like acceleration of a synucleinopathy in a transgenic mouse model.

Our aim in this study was to investigate experimentally the possible in vivo transmission of a synucleinopathy, using a transgenic mouse model (TgM83) expressing the human A53T mutated α-synuclein. Brain homogenates from old TgM83 mice showing motor clinical signs due to the synucleinopathy and containing insoluble and phosphorylated (pSer129) α-synuclein were intracerebrally inoculated in young TgM83 mice. This triggered an early onset of characteristic motor clinical signs, compared with uninoculated TgM83 mice or to mice inoculated with a brain homogenate from a young, healthy TgM83 mouse.

Transmission of prion strains in a transgenic mouse model overexpressing human A53T mutated α-synuclein.

There is a growing interest in the potential roles of misfolded protein interactions in neurodegeneration. To investigate this issue, we inoculated 3 prion strains intracerebrally into transgenic (TgM83) mice that overexpress human A53T α-synuclein. In comparison to nontransgenic controls, there was a striking decrease in the incubation periods of scrapie, classic and H-type bovine spongiform encephalopathies(C-BSE and H-BSE), with conservation of the histopathologic and biochemical features characterizing these 3 prion strains.

Emergence of classical BSE strain properties during serial passages of H-BSE in wild-type mice.

Background: Two distinct forms of atypical spongiform encephalopathies (H-BSE and L-BSE) have recently been identified in cattle. Transmission studies in several wild-type or transgenic mouse models showed that these forms were associated with two distinct major strains of infectious agents, which also differed from the unique strain that had been isolated from cases of classical BSE during the food-borne epizootic disease.

Methodology/principal Findings: H-BSE was monitored during three serial passages in C57BL/6 mice.