Table 1.

Type of stem cells based on their differentiation capacities

Differentiation capacity	Isolated cells	Origins & methods	Advantages	Disadvantages
Pluripotency	ESCs	1. Blastocyst; inner cell mass	● Differentiation into three germ layers	● Immunological concerns
		2. Somatic cell nuclear transfer (SCNT)	● Self-renewal and high replication	● Ethical debate
			● Approved by US FDA	● Potential for teratoma
	iPSCs	Reprogramming of somatic cells by gene transfer	● Less ethical concerns than ESCs	● Need method standardization
			● Patient-specific	● Potential for teratoma
			● Autologus	● Validation for safety
Multipotency	ASCs	Bone marrow, adipose tissue, umblical cord, amniotic fluid, placenta, CNS	● Less ethical concerns than ESCs and IPSCs	● Less cell proliferation
				● Limit differentiation potencial

ESCs : embryonic stem cells, US FDA : United States Food and Drug Administration, iPSCs : induced pluripotent stem cells, ASCs : adult stem cells, CNS : central nervous system