Clinical Application Status of Articular Cartilage Regeneration Techniques: Tissue-Engineered Cartilage Brings New Hope

Table 2

Advantages and limitations of the use of common cell types for articular cartilage regeneration.

Cell types		Advantages	Limitations
Autologous chondrocytes		(1) Naturally have a chondrocyte phenotype; (2) No immune rejection; (3) No disease transmission	(1) Limited number of cells; (2) The morbidity of the donor site; (3) Chondrocytes dedifferentiation during expansion; (4) Requires multiple surgeries; (5) Regenerate fibrocartilage; (6) Proliferation and differentiation potential decreased with age
MSCs	BMSCs/BMDCs	(1) Potential for chondrogenic differentiation; (2) Theoretically has unlimited self-renewal ability; (3) Can induce cartilage regeneration in situ	(1) Invasive surgery is needed for the harvesting; (2) Low cell content; (3) The morbidity of the donor site; (4) Tumorigenicity; (5) High variability in the chondrogenic differentiation potential of MSCs from different individuals; (6) The differentiated chondrocytes are prone to hypertrophic differentiation
	ADSCs	(1) Abundant sources; (2) Large number of cells; (3) Good immunomodulatory capacity; (4) Small invasive procedures to acquire cells	(1) Inferior potential for chondrogenesis; (2) Tumorigenicity; (3) High variability in the chondrogenic differentiation potential of MSCs from different individuals; (4) The differentiated chondrocytes are prone to hypertrophic differentiation
	PBPCs/PBMSCs	(1) Cells harvested with minimal trauma; (2) Low morbidity at the donor site	(1) Extremely low cell density; (2) Stem cell mobilization is needed, and the procedure is complex; (3) Tumorigenicity; (4) High variability in the chondrogenic differentiation potential of MSCs from different individuals
	UCB-MSCs/WJ-MSCs	(1) Cells harvested noninvasively; (2) Potential for chondrogenic differentiation; (3) Ability for unlimited self-renewal under controlled conditions; (4) Resistant to senescence	(1) Tumorigenicity; (2) Risk of disease transmission; (3) Lack of evidence from large-scale clinical trials
	SMSCs/SFMSCs	(1) Small invasive procedures to acquire cells; (2) Potential for chondrogenic differentiation	(1) Tumorigenicity; (2) Limited number of cells; (3) Lack of evidence from large-scale clinical trials
ESCs		(1) Ability for unlimited self-renewal under controlled conditions; (2) Capacity to differentiate into all mature cell types of the three germ layers, including chondrocytes	(1) Tumorigenicity; (2) Risk of disease transmission; (3) Immune rejection; (4) Ethical controversy
iPSCs		(1) Capacity to differentiate into all mature cell types of the three germ layers, including chondrocytes; (2) Ability for unlimited self-renewal under controlled conditions; (3) No ethical controversy; (4) Can be obtained from autologous adult cells	(1) Complicated preparation procedures and high technical requirements; (2) High cost; (3) Reprogramming efficiency still needs to be improved; (4) Tumorigenicity