Collagen-binding human epidermal growth factor promotes cellularization of collagen scaffolds

Previous studies have demonstrated that epidermal growth factor (EGF) can promote tissue regeneration effectively. The aim of the present study was to combine a collagen-binding domain (CBD) with native EGF (NAT-EGF) to form a fusion protein, aiming at that it could bind to collagen scaffolds specifically. This approach could restrict the diffusion of EGF despite of extracellular fluids and limit the release of EGF to surrounding tissues. Thus, the retained CBD-EGF would render a continual function during the tissue regeneration. In our study, in vitro bioactivity assay showed that there was no significant difference between CBD-EGF and NAT-EGF to stimulate human fibroblasts to proliferate. In the collagen-binding assay, CBD-EGF exhibited a specific binding ability to collagen compared to NAT-EGF. Finally, in vivo experiment demonstrated that CBD-EGF-loaded collagen membranes uniformly possess a high capability to promote cellularization of scaffolds as compared with that of NAT-EGF. All results aforementioned suggested that collagen loaded with CBD-EGF is a functional biomaterial with potential clinical applications.