Mesenchymal stem cells-based drug delivery systems for diabetic foot ulcer: A review

Table 1 Summary of four mesenchymal stem cells-based drug delivery systems for diabetic foot ulcer

Scaffold	Advantage	Disadvantage
Hydrogel	Excellent biocompatibility and biodegradability[33-36], low cytotoxicity[74-79], with similar structure as human tissues[77-82], longer lifetime, higher water absorption capacity[90-95], and greater gel strength[107-111]	Weak mechanical strength and high batch-to-batch variability[161-165]
Fiber	Well-mimicking the human tissues and excellent cell attachment[112-118]	Small pore size limiting cell migration[46-48]
Sponge	Appropriate microenvironment for cell attachment, migration, and nutrient transition[59-63]; Exceptional ability of loading, retaining and releasing of fluids[103-107]	Longer time for fabrication procedure[79-83];Requirement to adjust according to cell type and host tissues[137-142]
Decellularization	Mimicking an optimal non-immune environment with native three-dimensional structures and various bioactive components[121-124]; Flexible mechanical properties[127-133]; Satisfactory mechanical strength[139-142]	Complete decellularization is complex and time consuming[152-156]