Table 1.

Comparison of different cell origins used for reprogramming

Cell Source	Derivation	In vitro Expansion	Reprogramming Efficiency (4Factor)	Reprogramming Speed	Reprogramming Factors	References
Skin Fibroblasts	Skin Biopsy	Yes	~0.01% (Adult cells)	>21 days	OSKM, OSK, OSNL	1–7
Neural Stem Cells	NA	Yes	0.004% (1Factor, Fetal cells)	>7–8 weeks (1Factor)	OK, O	9
Keratinocytes	Skin Biopsy	Yes	~1% (neonatal and juvenile cells)	>10 days	OSKM, OSK	10
CD34 Blood Cells	Peripheral blood undergo G-CSF stimulation	No	~0.01–0.02% (Adult cells)	>14 days	OSKM	11
Adipose Stem Cells	Lipoaspiration	No	~ 0.2% (Adult cells)	>13–14 days	OSKM	15
Melanocytes	Skin Biopsy	Yes	~0.05% (not known)	>10 days	OSKM, OKM	14
Cord Blood Cells	Collected at birth from cord blood	No	~ 0.01% (neonatal cells)	>12–15 days	OSKM, OSNL, OSK, OS	17, 18

O: Oct4, S: Sox2, K: Klf4, M: c-MYC, N: Nanog, L: Lin-28, NA: Not Applicable