(a) Human iPSC-derived astrocyte supports the replication of CJD prions. In contrast to differentiated astrocytes, however, human iPSC-derived APCs failed to replicate human prions despite expression of PrPC. It is still unclear whether human iPSC-derived neurons, oligodendrocytes, and their precursors (NPC and OPC, respectively) are capable of supporting human prion replication. (b) Rodent studies have showed that differentiated neurons and astrocytes, but neither undifferentiated neurospheres nor oligodendrocytes, support prion replication.