| 초록 |
For healing of any kind of bone defect with biomaterials three steps of osteoblastic cells should be occurred one after one- attachment, migration and differentiation. From our previous study, we found that chitosan-hyaluronic acid (CS-HA) polyelectrolyte scaffold is very much effective for immobilization of bone morphogenetic protein-2 (BMP-2), which means it possesses osteoinductivity. Biphasic calcium phosphate (BCP) has already been used clinically as an osteoconductive material. Our main idea in this study is combining of this both osteoconductive and osteoinductive scaffolds as core and shell will serve the purpose of cell migration in the defect site. To evaluate our idea, we undertook several physical characterizations such as SEM, porosity, compressive strength, degradation etc. Due to stable BCP shell structure, swelling of CS-HA core was controlled. Beside of MTT and Confocal microscopy as in vitro studies with preosteoblast cells MC3T3-E1, we introduced a novel experimental system to evaluate 3-D cell migration. We found in those studies that smaller pores in the shell structure of BCP and bigger pores in the core CS-HA served the enhancement of cell attachment, proliferation and migration. As all of these cell cycle steps were influenced by our material design, the final step, osteodifferentiation, was also significantly enhanced as all of four markers in reverse transcriptase PCR (RT PCR) study were statistically improved. Thus a core shell structure of CS-HA and BCP scaffold can strongly be recommended for bone tissue engineering. |
