Experimental study of repairing fat defect with human hair keratin material

Objective To investigate the feasibility of adipogenesis from human hair keratin (HHK) material, so as to provide a new method for fat defect and depression deformity. Methods 3 Tibet mini-pigs were used. 8 fat defects( 1. 5 cm in diameter) were made bilaterally on the back. The ballshaped HHK material was implanted to repair the defects at one side. The defects at contralateral side were as controls. The absorption of the HHK material and adiogenesis were studied histologically. Results 2 weeks after implantation, connective tissue and capillary grew into the porous HHK material. 4 weeks after implantation, HHK material was almost totally absorbed, leaving some material debris and foreign body granuloma. Around them, there were clusters of adipocyto. 6 weeks after implantation, the HHK material was totally degraded and the granuloma was disappeared, and then de novo adipose tissue was observed. Its volume was close to the volume of peripheral HHK material that was planted originally. 10 weeks later, the new-formed fat tissue had less fibres and was very similar to the normal fat. Conclusions New adipose tissue can be formed after HKK material implantation. It can also be remodeled to be similar to normal fat. Key words: Fat defect; Human hair keratin; Adipose tissue