Abstract
Purpose: :
Epithelial downgrowth and keratoprosthesis extrusion may be hindered by complete epithelial coverage over the anterior surface. Here, we investigate the effects of epidermal growth factor (EGF) and heparin-binding epidermal growth factor (HB-EGF) tethered within dendrimer crosslinked collagen (CG) gels, and released HB-EGF from heparinized dendrimer crosslinked collagen (CHG) gels, in vitro.
Methods: :
Radiolabeled HB-EGF was immobilized to and released from CHG gels. The release of HB-EGF was measured under physiologically relevant conditions and bioactivity determined with an ELISA and through in vitro cell studies with human cornea epithelial cells (HCEC) via cell proliferation. Tethering of HB-EGF and EGF was achieved through amide reaction with CG gels (surface modification) and with dendrimers prior to collagen gel fabrication (bulk modification). Growth factor activity was also investigated with HCECs cultured on the gels in vitro.
Results: :
In vitro
Conclusions: :
CHG gels are able to act as delivery vehicles for soluble HB-EGF delivery, via heparin, while growth factors can be tethered to CG gels. Both maintain growth factor bioactivity and have potential for improving native host integration with an artificial cornea as demonstrated through corneal epithelial cell interactions.
Keywords: keratoprostheses • cornea: epithelium • growth factors/growth factor receptors