Synergistic effect between 2-N,6-O-sulfonated chitosan and bone morphogenetic protein-2

The molecular structure of sulfonated chitosan is similar to heparin, and it has been proved to have some heparin functions. Studies have shown that heparin and bone morphogenetic protein-2 (BMP-2) have synergistic effects, but heparin has limitations in clinical application. In this paper, the synergistic effect of 2-N,6-O-sulfonated chitosan (26SCS) and BMP-2 was studied. The preparation of 26SCS was explored and 26SCS was co-cultured with bone marrow mesenchymal stem cells (BMSCs) to study the effects of 26SCS on the proliferation, adhesion behavior and osteogenic differentiation of BMSCs. The synergistic mechanism of 26SCS and BMP-2 was explored by circular dichroism and isothermal calorimetric titration. The results showed that 26SCS affected the secondary structure of BMP-2 protein, mainly caused the significant change of antiparallel conformation in β-fold, and then improved the biological activity of BMP-2 and showed a dose-dependent manner. 26SCS was expected to be a synergistic factor of BMP-2.