Effect of Keratin-Based Biocomposite Hydrogels as a RhBMP-2 Carrier in Calvarial Bone Defects Mouse Model

Abstract

Recently, in human medicine and veterinary medicine, interest in synthetic bone graft is increasing. Among them, bone morphogenic protein (BMP) is currently being actively researched and applied to clinical trials. However, BMP has the disadvantage of being expensive and easily absorbed into surrounding tissues. Therefore, BMP requires the use of small amounts and rhBMP (recombinant human bone morphogenetic protein)-2 carriers that can be released slowly. Hydrogel has the property of swelling a large amount of water inside when it is aqueous solution, and when it is, it consists of more than 90 percent water. Using these properties, hydrogels are often used as rhBMP-2 carrier. The scaffold used in this study is a hydrogel made from which keratin is extracted using human hair and based on it. In this study, we wanted to see the effect of bone formation in the calvarial defect model by using keratin-based hydrogel made with human hair as a scaffold. The experiment was conducted by dividing 3 groups a total of 12 mice. Calvarial bone defect is set to all 4 mm diameters. Bone formation was evaluated by using gross evaluation, micro-computed tomography (micro-CT), immunohistochemistry. Groups using keratin-based hydrogel were significantly observed compared to Group 1s, and the most bone formations were found when rhBMP-2 and hydrogel were used. This represents the superiority of the functions of the rhBMP-2 carrier by a new material, keratin-based hydrogel. Through gross evaluation, micro-CT, and immunohistochemistry, we can confirm that keratin-based hydrogel is a useful rhBMP-2 carrier.