PRNP has been identified in the EVs derived from both CSF113 and blood.114 Accumulating evidence further suggests a key role of EVs in both the pathogenesis and propagation of prion diseases.115, 116, 117 One of the initial studies has demonstrated that PRNP-expressing cell line (RK13) robustly secreted PRNP through exosomes.118 Vella et al.119 further showed that exosomes released from PRNP-infected neuronal cell line (GT1-7) also induced prion propagation in both neuronal as well as non-neuronal cells. Here, PRNP is linked to prion disease.