Fabrication and biocompatibility assessment of the scaffold with biomimetic interconnected macropore structure / 中国组织工程研究

ABSTRACT

BACKGROUND: Development of bone tissue engineering provides a new method to solve bone defect repair. Scaffold material and structure construction are issues of concern. OBJECTIVE: To fabricate a silk fibroin and hydroxyapatite scaffold with biomimetic interconnected macropores structure using the paraffin-sphere leaching technology and to evaluate its possibility of cytocompatibility. METHODS: The scaffold with biomimetic interconnected macropores structure was made by the paraffin-sphere leaching technology. The structure of scaffold was observed by the stereomicroscope and scanning electron microscope. The pore size and elasticity modulus were calculated. Passage 3 rabbit adipose-derived mesenchymal stem cells were seeded into the scaffold. The cell viability was detected by live/dead staining at 48 hours after culture. The cell adhesion was observed by hematoxylin-eosin staining at 1 week of culture. The scaffold-cell composite was observed under scanning electron microscope at 3 days of culture. The cell proliferation was detected by the cell counting-kit 8 assay at 1, 3, 5 and 7 days of culture. Those cells cultured alone were considered as control group. RESULTS AND CONCLUSION: (1) Stereomicroscope showed the ivory silk fibroin/hydroxyapatite scaffold. Scanning electron microscope revealed pore structures in cross-section and longitudinal-section with good connectivity. The scaffold pore size was (362.23±26.52) μm and the elasticity modulus was (54.93±5.44) kPa. (2) Scanning electron microscope showed that adipose-derived mesenchymal stem cells adhered and stretched well in the pore wall and connected pore, secreted abundant extracellular matrix, and filled in the pores of silk fibroin/hydroxyapatite scaffold. (3) Hematoxylin-eosin staining results found that adipose-derived mesenchymal stem cells evenly adhered onto the inner wall of silk fibroin/hydroxyapatite scaffold, and proliferated well. (4) Live/dead staining revealed a good viability of adipose-derived mesenchymal stem cells. (5) Cell counting-kit 8 assay results showed the good proliferation of adipose-derived mesenchymal stem cells on the scaffold. (6) To conclude, the silk fibroin/hydroxyapatite scaffold possesses good pore size and cytocompatibility.