In vivo biological responses and bioresorption of tilapia scale collagen as a potential biomaterial.

To date, collagen for biomedical uses has been obtained from mammalian sources. The purpose of this study was to evaluate the in vivo biological responses and bioresorption of collagen obtained from tilapia (Oreochromis niloticas) scales as compared to those of collagen from porcine dermis. Collagen sponges with micro-porous structures were fabricated from reconstituted collagen fibrils using freeze-drying and cross-linked by dehydrothermal treatment (DHT treatment) or additional treatment with a water-soluble carbodiimide (WSC treatment). The mechanical properties of the tilapia collagen sponges were similar to those of porcine collagen sponges with the same cross-linking methods, where WSC treatment remarkably improved the properties over DHT treatment alone. The pellet implantation tests into the paravertebral muscle of rabbits demonstrated that tilapia collagen caused rare inflammatory responses at 1- and 4-week implantations, statistically similar to those of porcine collagen and a high-density polyethylene as a negative control. The bioresorption rates of both the collagen implants were similar, except for the DHT-treated tilapia collagen sponges at 1-week implantation. These results suggest that tilapia collagen is a potential alternative to conventional mammalian collagens in biomedical uses.