Growth factor functionalized biomaterial for drug delivery and tissue regeneration

Abstract

Elastin-like polypeptides are a class of naturally derived and non-immunogenic biomaterials that are widely used in drug delivery and tissue engineering. Elastin-like polypeptides undergo temperature-mediated inverse phase transitioning, which allows them to be purified in a relatively simple manner from bacterial expression hosts. Being able to genetically encode elastin-like polypeptides allows for the incorporation of bioactive peptides, thereby functionalizing them. Here, we report the synthesis of a biologically active epidermal growth factor–elastin-like polypeptide fusion protein that could aid in wound healing. Epidermal growth factor plays a crucial role in wound healing by inducing cell proliferation and migration. The use of exogenous epidermal growth factor has seen success in the treatment of acute wounds, but has seen relatively minimal success in chronic wounds because the method of delivery does not prevent it from diffusing away from the application site. Our data show that epidermal growth factor–elastin-like polypeptide retained the biological activity of epidermal growth factor and the phase transitioning property of elastin-like polypeptide. Furthermore, the ability of the epidermal growth factor–elastin-like polypeptide to self-assemble near physiological temperatures could allow for the formation of drug depots at the wound site and minimize diffusion, increasing the bioavailability of epidermal growth factor and enhancing tissue regeneration.