Table 3.

Pros and Cons of iPSC-derived DA neurons vs. iDA neurons.

Attributes	iDA Neurons	iPSC-derived DA Neurons
Technical Challenges	Can be readily implemented without stem cell experience; only need good viruses.	Needs expertise on stem cell culture and differentiation; technically demanding and labor intensive.
Length of Derivation	Neuronal markers within 10 days; mature neurons in ~ 30 days or more.	Neuronal markers within 30 days; mature neurons in ~50 days or more.
Source Durability	Source fibroblasts may be limiting; embryonic fibroblasts are more expandable.	iPSCs are stable lines that can be differentiated to unlimited amount of DA neurons.
Epigenetics of Age	Better preservation of age-associated epigenetic information.	Reversion of age to embryonic state in iPSCs, may be reestablished in differentiation.
Mitotic Cells	Small percentage of unreprogrammed mitotic cells with low proliferative potential.	May contain undifferentiated cells with high proliferative potential.