TABLE 1.

Characteristics and regulatory networks of FCSCs in animals and humans.

Species	Markers	Characteristics	Regulatory networks	Author and year
Rat	Positive: CD90, CD44, CD29, CD105, CD146 Negative: CD45, CD79a, CD11b	Reside in the SZ; Chondrogenic, osteogenic, and adipogenic differentiation capacity in vitro; High colony formation ability compared to that of cartilage cells; Spontaneous osteogenesis and chondrogenesis when transplanted in vivo	Wnt: deplete FCSCs pool and enhance chondrogenesis Notch: promote differentiation of FCSCs into chondrocytes and osteoblasts SOX9: induce chondrogenesis of FCSCs	Embree et al., 2016,Nathan et al., 2018,Ruscitto et al., 2020 Bi et al., 2020
Mouse	α-SMA+ cells in the SZ Notch+ cells during embryonic development	Reside in the SZ and gradually infiltrate into the mature chondrocyte layer	Notch: participate in TMJ morphogenesis and cartilage-to-bone transdifferentiation in TMJ OA	Embree et al., 2016,Ruscitto et al., 2020
Human	Positive: CD44, CD73, CD90, CD105 Negative: CD29, CD34, CD45	Spindle-shaped cells; Comparable propagation ability, apoptosis rate, and colony forming efficiency to hOMSCs; Weak migration capability; Chondrogenesis under chondrogenic induction in vivo	SOX9: induce chondrogenesis of FCSCs	Bi et al., 2020
Rabbit	N/A	N/A	SOST: maintain the FCSC pool	Embree et al., 2016

FCSCs, fibrocartilage stem cells; SZ, superficial zone; hOMSCs, human orofacial bone marrow-derived mesenchymal stem cells; SOX9, Sry-related HMG box-9; TMJ, temporomandibular joint; OA, osteoarthritis; SOST, sclerostin.