Effect of a novel recombinant protein of fibronectinIII7-10/cadherin 11 EC1-2 on osteoblastic adhesion and differentiation.

The limitations of specific adhesion and osteoblastic differentiation are current problems in bone tissue engineering. The aim of this study was to investigate the effect of a novel recombinant protein of fibronectin module III7-10/cadherin 11 EC1-2 (rFN/CDH) on cell adhesion and differentiation. Gene coding rFN/CDH was engineered by a homology modeling strategy, and an expression plasmid was constructed by standard DNA techniques. The rFN/CDH protein was expressed in Rosetta-gami (DE3), an improved Escherichia coli system. MC3T3-E1 cell centrifugal adhesive assay indicated that the adhesive capacity of rFN/CDH was significantly improved. Quantitative analysis of two osteogenic markers, osteocalcin mRNA expression and alkaline phosphatase activity, indicated that they were further up-regulated when human mesenchymal stem cells were cultured for 7-10 d on rFN/CDH pre-coated surfaces. These results suggest that rFN/CDH possesses an enhanced dual biofunctionality in osteoblastic adhesion and differentiation, and a promising application can be expected in biomimetic strategies and biomaterial development.