Table 4.

Preclinical studies examining the use of different combinations of MSC-subpopulations and hydrogels for cartilage engineering.

Author	Year	Animal; Defect Type	Cell Source	Hydrogel	Study Design	Results
Lv et al. [88]	2018	Sheep OA	ADMSCs	HA hydrogel	ADMSCs (high dose) + hydrogel ADMSCs (low dose) + hydrogel Stromal vascular fraction Hydrogel Saline	Superior results in the delay of OA progression and cartilage repair when using ADMSCs and hydrogels
Feng et al. [89]	2018	Sheep OA	ADMSCs	HA hydrogels	ADMSCs (high dose) + hydrogel ADMSCs (low dose) + hydrogel Hydrogel Saline	Anti-inflammatory effects and repair tissue with typical articular cartilage features when using ADMSCs and hydrogels
Sevastianov et al. [90]	2021	Rabbit Knee OA	ADMSCs	COL hydrogels	ADMSCs + hydrogels ADMSCs + decellularized porcine articular cartilage	Cell-laden hydrogels were superior in stimulating cartilage repair in vivo MSCs cultured in the presence of decellularized porcine articular cartilage formed more cartilage-specific ECM components
Jia et al. [91]	2019	Rabbits Osteochondral defects of the knee	Synovial fluid-derived MSCs	CH hydrogels	MSCs + hydrogel Hydrogel Untreated controls	Improved macroscopic appearance and histological results in the group treated with MSCs + hydrogels
Wu et al. [92]	2019	Minipigs Osteochondral defects	Umbilical cord-derived MSCs	HA hydrogels	MSCs + hydrogel Untreated controls	Effective treatment of cartilage defects using MSCs + hydrogels in minipigs
Li et al., [93]	2018	Rats Osteochondral defect of the knee	Arthroscopic flushing fluid-derived MSCs	Polypegda/HA hydrogels	MSCs + hydrogel Hydrogel Untreated controls	Significantly improved

ADMSCs: adipose-derived mesenchymal stromal cells; CH: chitosan; HA: hyaluronic acid; OA: osteoarthritis.