Table 3. Comparison between stem cells.

Cell types	Category	Advantages	Disadvantages
ESCs	–	Unlimited proliferative ability Pluripotent	Risk of teratoma formation (Ethical issue with the use of embryos for cell isolation The challenge to acquire patients’ own ESCs
iPSCs	–	Unlimited proliferative ability Pluripotent No ethical concern for tissue source	Risk of teratoma formation Genotype change in the transfection process Low efficiency of the transfection process Less reported in tendon regeneration
MSCs	BMSCs ADSCs TDSCs	Low cancerization rate Easily available tissue source for cell isolation No ethical concern for tissue source	Senescence and loss of stem cell characteristics as the number of passages increase in vitro

ESCs, embryonic stem cells; iPSCs, induced pluripotent stem cells; MSCs, mesenchymal stromal cells; BMSCs, bone marrow-derived mesenchymal stromal cells; ADSCs, adipose-derived stem cells; TDSCs, tendon-derived stem cells.