Immunopurified aggregates of PrP^Sc support <i>in vitro</i> misfolding of PrP^C by PMCA.

<p>Aggregates of PrP^Sc immunopurified from P3 fractions of RML-infected C57BL/6 mice (lanes 1–8), or immunoprecipitates of P3 fractions of <i>Prnp</i>^0/0 mice (lanes 9–12) were resuspended in PBS (lanes 1–4 and 9–12) or immobilized on glass coverslips by ultracentrifugation (lanes 5–8), and mixed with brain homogenates of Tg(WT) mice overexpressing 3F4-tagged PrP^C. Mixtures were either rapidly frozen (lanes 1 and 2, 5 and 6, 9 and 10) or subjected to 90 cycles of sonication/incubation (lanes 3 and 4, 7 and 8, 11 and 12). Samples were then either subjected to proteinase K (PK) (lanes 2, 4, 6, 8, 10 and 12), or left undigested (lanes 1, 3, 5, 7, 9 and 11). All samples were analyzed by Western blotting with 3F4 antibody.