Figure 4. Highly efficient amplification of 127S prions using concentrated cell lysate alone by a single round of Cell-mb-PMCA.

(A) P2FJ6 cell lysates were concentrated with regard to the total protein concentration and were directly seeded with serial 10-fold dilutions of tg338 brain homogenate containing 127S prions for a single round Cell-mb-PMCA. (B) In parallel, the same dilutions were submitted to mb-PMCA by using tg338 brain homogenate as substrate. Unseeded controls (lanes U) and the amplified samples were digested with PK before western blotting analysis for PrP^res content (Sha31 antibody). The first lane contains undigested normal tg338 mouse brain. (C) Regression analysis of 127S endpoint dilution achieved by cell-mb-PMCA versus total protein concentration in the P2FJ6 cell lysate.