Crosslinking heparin to collagen scaffolds for the delivery of human platelet-derived growth factor

Platelet-derived growth factor (PDGF) plays an important role in tissue regeneration and wound repair. However, the lack of effective delivery and the efficient targeting specificity limits its clinical applications. Here, heparin possessing PDGF binding domain was crosslinked to the collagen-based demineralized bone matrix (DBM) for the delivery of human PDGF(HC-PDGF). In in vitro experiments, heparin improves the binding of PDGF to collagen. In vitro activity assay indicates that collagen-heparin-PDGF (CH-PDGF) promotes human fibroblasts to proliferate on collagen gel. In addition, HC-PDGF stimulates cells to migrate into DBM scaffolds after implantation. The histological analysis shows that HC-PDGF promotes vascularization of the implants. In summary, heparin-DBM/PDGF could prevent the diffusion of PDGF, prolong its activity, and promote the cellularization and vascularization of the scaffold.