Promotion of Cell Migration into a Hydrophobically modified Alaska Pollock Gelatin-Based Hydrogel

In situ chemically cross-linkable hydrogels composed of hexyl group-modified Alaska pollock-derived gelatin (C6-ApGltn) and poly(ethylene glycol)-based four-armed cross-linker is developed. Water droplets are quickly absorbed into the C6-ApGltn hydrogel in the first 10 s compared with original ApGltn (Org-ApGltn), and the final contact angle on C6-ApGltn is significantly lower than that on Org-ApGltn. Using a fluorescent probe, an increase in fluorescence intensity on C6-ApGltn compared to that on Org-ApGltn is found, indicating the formation of a hydrophobic pocket. Moreover, the promotion of cell migration into the C6-ApGltn hydrogel is observed in vitro and in vivo compared with Org-ApGltn hydrogel, despite no significant difference in elastic modulus. Therefore, the C6-ApGltn hydrogel could potentially be used as a supporting material for cell transplantation and tissue/organ engineering.