TABLE 1.

Natural materials used for meniscus tissue engineering.

Materials	Processing technology	Repair area	Comparator	Loaded impact factors	Loaded cells	Results	References
Collagen	Electrospinning	In vitro culture	Scaffold with hydrogel or without hydrogel, with different cells	TGF-β1, TGF-β3	Meniscus cell, BMSC, synovial cell, cell from the IPFP	Collagen scaffolds with hydrogels loaded with IPFP cells yielded the highest cell densities with greater deposition of Col I and the highest mechanical properties compared to other cells.	Baek et al. (2018)
	Electrospinning	Ex vivo repair model	Collagen scaffold with meniscus cells	-	Meniscus cell	Cell-seeded collagen scaffolds resulted in better integration of new tissue with native tissue.	Baek et al. (2016)
	Freeze-drying	Partial meniscus repair	Intra-articular injections of vehicle or gefitinib	gefitinib	-	Intra-articular injection of gefitinib and implantation of a collagen scaffold enhanced meniscal regeneration.	Pan et al. (2017)
	Chemical crosslinking	In vitro culture	Scaffold with different PRP or whole blood	PRP	Meniscus cell	PRP has a higher effect on meniscus cell growth and gene expression than whole blood	Howard et al. (2014)
	Photocrosslinking	Partial meniscus repair	Cells expanded with conditioned medium or growth medium	TGF-β3	TMSC	Chondrogenic induced cells in the scaffold have more cell proliferation, GAG and collagen deposition for the best meniscal repair	(Heo et al., 2016; Koh et al., 2017)
Silk	Salt porogen leaching, freeze-drying	In vitro culture	Different layers of meniscal scaffold	-	Fibroblasts at the periphery and chondrocytes at the scaffold center	Chondrocytes in the inner region enhanced Col I and Col II production, and fibroblasts in the outer region enhanced Col I production.	Mandal et al. (2011a)
	3D printing	Subcutaneous implantation	-	-	Fibrochondrocytes	The scaffold supported to maintain cell phenotype.	Bandyopadhyay & Mandal, (2019)
	Processing into porous matrix	Partial meniscus repair	Meniscectomy	-	-	The scaffold provided a degree of articular cartilage protection, improved tibiofemoral contact pressures.	(Gruchenberg et al., 2014; S. Stein et al., 2019a; S. E. C. Stein et al., 2019b)
	Electrospinning	Partial meniscus repair	Meniscectomy	Sr2+	-	The SP-Sr group regenerated the meniscus, which provided better protection to the articular cartilage and slowed down the progression of arthritis.	(Y. Li Y et al., 2020)
Hyaluronic acid	3D printing	Partial meniscus repair	Meniscectomy	-	-	Fibrochondrocyte tissue growed inward and integrated firmly with the surroundings.	Ghodbane et al. (2019b)
	Photocrosslinking	In vitro culture	Agarose, gelatin, and PCL	-	Fibrochondrocyte	Cells in MeHA were round, and the ratio of deposited Col II to Col I was close to the value of the inner area region of the native meniscus.	Bahcecioglu et al. (2019b)
	Electrospinning	Subcutaneous implantation	-	-	Fibrochondrocyte	The stiffness of the fibers influenced cell behavior, and cellularity and collagen deposition were greater in the stiffer scaffold.	Song et al. (2020)
Chitosan	Gel casting	In vitro culture	Different ratios of chitosan and gelatin scaffolds	-	-	All groups of scaffolds had good meniscal cytocompatibility and the scaffolds conforming to the mechanical strength of the different layers of the meniscus were prepared by different ratios of chitosan and gelatin.	Sarem et al. (2013)
	Crosslinking and dialyzing	Total meniscus repair	PVA/CS scaffold with different seed cells	-	ADSC and AC	Extracellular matrix-rich meniscus tissue was regenerated in all experiment groups, but the meniscus in the AC group had the best protection of the femur and tibia.	Moradi et al. (2017)
Extracellular matrix	Freeze-drying	Ex vivo repair model	Different amounts of porcine MDM	-	-	Endogenous meniscal cells and MSCs migrated to the scaffolds, 8% MDM scaffold promoted repair of partial meniscal defects.	Ruprecht et al. (2019)
	Freeze-drying	Ex vivo repair model	Meniscus suture	PRP	Fibrochondrocyte	The scaffold promoted cell proliferation and infiltration, generated an amorphous extracellular matrix.	Monibi et al. (2016)
	Freeze-drying	Subcutaneous implantation	Sham-operated	-	-	No sign of inflammation showed on the surrounding of tissues.	Chen et al. (2015)
	Freeze-drying	Total meniscus repair	DCB scaffold, ECM/DCB scaffold	-	-	The ECM/DCB scaffold promoted fibrochondrocyte proliferation and secretion of collagen and GAG, and also promoted meniscal regeneration and prevented cartilage degeneration.	Yuan et al. (2016)
	Thermoresponsive gel	In vitro culture	-	-	Chondrocyte, fibroblast	Cell infiltration and proliferation	Wu et al. (2015)
	Thermoresponsive gel	Partial meniscus repair	Collagen scaffold	-	BMSC	ECM scaffolds induced fibrochondrogenesis of BMSCs and enhanced overall healing and cartilage protection of the meniscus	Zhong et al. (2020)