PRNP and prion disease: Negatively charged macromolecules or polyanions, including nucleic acids [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], phospholipids [21], [22], [23], [24] and glycosaminoglycans (GAGs) have been implicated as facilitating cofactors in the conversion of PrPC to PrPSc and thereby in the transmission and pathogenesis of prion disease.