PRNP and prion disease: These diseases all share the same pathological characteristics of spongiform degeneration, neuronal death and astrocytic and microglial proliferation (Zhu et al., 2014; Ji et al., 2017; Shah et al., 2017a).The underlying cause of prion disease is the conformational conversion of a cellular prion protein (PrPC) to a misfolded isoform (PrPSc), which has a higher proportion of beta-sheets in place of the normal alpha-helices in PrPC and is protease-resistant (Prusiner, 1998; Wang et al., 2015).