Figure 4. . Relative conversion efficiency of human PrP (129M) by different animal prion disease samples. Brain homogenates from animal prion diseases were seeded at different volumes adjusted to give roughly equivalent amounts of seeding PrPres and amplified by using PrP 129M-containing human brain substrate. Human PrPres formation was detected by the 3F4 antibody (A) and seed and newly formed PrPres detected using the 6H4 antibody (B). PrP, protein prion; PrPres, protease-resistant PrP; M, molecular marker; BSE, bovine spongiform encephalopathy; CWD, chronic wasting disease; L-BSE, L-type BSE; H-BSE, H-type BSE; vCJD variant Creutzfeldt-Jakob disease; M, molecular marker.