BMSCs are multipotent stem cells that can differentiate into many
cell types, including adipocytes, chondrocytes, acinar cells, osteoblasts,
and salivary epithelial cells [33–35]. BMSCs are efficient seed cell source
to promote cartilage regeneration. In our study, COL/SF composite
scaffold induced BMSC proliferation. The number of cells on the composite
with an optimal ratio of 7:3 was the highest among all ratios
after in vitro biocompatibility test was performed for 5 d (Fig. 1D).
This finding may be attributed to 7:3 composite with appropriate
pore structure, porosity, and pore diameter, which are necessary to
promote cell adherence and distribution. AO/EB fluorescence staining
results revealed that BMSCs on extraction solution exhibited enhanced
cellular growth behavior without signs of apoptosis (Fig. 3).
TGF-β1 is a bioactive factor extensively used in cartilage tissue engineering,
this factor can stimulate chondrogenic differentiation of BMSCs