(194f) Growth Factor Binding Peptides in PEGDA Based Wound Dressings to Promote and Enhance Healing in Diabetic Ulcers

Living with diabetes can lead to slow wound healing, the development of ulcers and in 84% of cases, limb amputation. The estimated annual direct cost in the US for the treatment of chronic wounds associated with diabetes is approximately $6–$15 billion [1]. The standard therapies to treat diabetic wounds include the control of acute inflammation, debridement and the use of the appropriate wound dressings [2]. To address these challenges some wound dressings deliver growth factors (GF) such as TGF-β1 and VEGF to control the inflammatory response and enhance healing. Despite the advantages of these types of dressings, they have limited use due to low availability, high cost, and the risk of a strong immunological response by the introduction of a foreign source of GFs [2]. In this work we explored the fabrication of a new family of dressings that uses GF binding peptide sequences as a strategy to sequester endogenous GF directly from the would site. By using endogenous GF enriched surfaces in the dressing, the proliferation and formation of new tissue can be stimulated while regulating the immune response of the tissue. Toward this end, poly(ethylene glycol) diacrylate based hydrogels were conjugated via NHS chemistry with synthetic peptide sequences with the capacity to physically bind TGF-β1 and VEGF. The conjugation of the peptide sequences to the PEG derivative ARCYL-PEG-NHS and PEGDA hydrogels was confirmed by ¹H-NMR and ATR-FTIR spectroscopy. The capacity of the proposed dressings to sequester and retain TGF-β1 and VEGF was qualitatively evaluated using the CBQCA protein quantification assay. The biological response of human skin cells including dermal fibroblast and keratinocytes to physically bound TGF-β1 or VEGF was also evaluated in terms of cell proliferation and phenotypical expression.

1. Brem, H., et al. J Clin Invest. 2007 117:1219–1222.
2. Andreu, V., et al. Materials 2015 8:5154-5193.

This work was supported by a grant from the San Antonio Area Foundation (2017 Biomedical Research grant).