Kurt et al. recently reported that normal brain homogenate from Syrian hamsters effectively supports the amplification of PrPres from CWD seeds in serial PMCA. Building on similar findings previously made in our laboratory we also used hamster NBH as substrate for our PMCA analyses. We found that PrPres generated by PMCA after Ac-YVAD-pNA seeding with CWD- or 263K scrapie agents did not exhibit significant differences in the glycosylation- or electrophoretic migration patterns. As a safeguard to PMCA specificity safety measures aimed at preventing inadvertent cross-contamination with both prions from cervids or hamsters were implemented. Specifically, we sealed our PMCA reaction tubes with parafilm and paraffin wax, performed all pipetting steps exclusively with plugged single-use pipette tips, and changed gloves each time before handling a new PMCA sample. With these safety measures in place unseeded controls in which PMCA was performed with normal hamster brain homogenate only did not produce any unspecific PrPres staining in our experimental setup. Our findings were obtained by an alternative methodology to bioassays in animals but are consistent with the observations reported by Angers et al.. They may also provide an explanation for the negative findings by Jewell et al. in skeletal muscle, since our Western blot results indicate a substantially lower concentration of PrPTSE in such tissue than reported for heart muscle. Yet, it has to be noted that our assessments of PrPTSE levels in skeletal CINK4 muscles were based on findings in presumably pre- or subclinically infected animals. Therefore, the concentration of PrPTSE in skeletal muscles of WTD with clinically manifest CWD may possibly exceed our estimate which refers to clinically inconspicuous animals that are more likely to enter the human food chain. Our tissue blot findings in skeletal muscles from CWDinfected WTD would be consistent with an anterograde spread of CWD prions via motor nerve fibres to muscle tissue. Similar neural spreading pathways of muscle infection were previously found in hamsters orally challenged with scrapie and suggested by the detection of PrPTSE in muscle fibres and muscle-associated nerve fascicles of clinically-ill non-human primates challenged with BSE prions.