Oxidized starch cross-linked porous collagen-based hydrogel for spontaneous agglomeration growth of adipose-derived stem cells

Many strategies have been employed to artificially reconstruct adipose tissue in tissue engineering. The functionalization and survival of reconstructed adipose tissue depend on sufficient angiogenesis. Notably, agglomeration growth of adipose-derived stem cells (ASCs) is beneficial to promoting angiogenesis. Herein, we present a porous collagen-based hydrogel for spontaneous agglomeration growth of ASCs to promote angiogenesis. Oxidized starch with different oxidation degree was prepared and used to cross-link collagen to fabricate the porous hydrogel. The gelation time and pore size of hydrogels can be controlled by adjusting the oxidation degree of starch. Crosslinking enhances the mechanical properties, inhibits the swelling and biodegradation of the hydrogels. The hydrogels possess good blood compatibility and cytocompatibility. Significantly, ASCs tended to adhere to the hydrogels and spontaneously grew into spheres along with time. Effective expression of vascular endothelial growth and fibroblast growth factors were observed. Overall, the hydrogels have application prospects in vascularized adipose tissue engineering.