Release of functional fibroblast growth factor-2 from artificial inclusion bodies.

Growth factors are required for cell proliferation and differentiation under physiological conditions but especially in the context of regenerative medicine. The time-prolonged administration of those factors has been explored using different sustained drug delivery systems. These platforms include natural materials such as bacterial inclusion bodies (IBs) that contain chaperones and other bacterial components that might favour protein release. Being successful from a functional point of view, IBs pose regulatory concerns to clinical applications because of the mentioned presence of bacterial cell components, including endotoxins. We have here explored the release and activity of the human fibroblast growth factor-2 (hFGF-2) from a novel synthetic material, namely artificial IBs. Being chemically homogenous and compliant with regulatory restrictions, we wondered if these materials would effectively release functional proteins in absence of accompanying bacterial agents. The data provided here fully supports that artificial hFGF-2 IBs act as true and efficient secretory granules and they slowly disintegrate in cell culture to promote wound healing in an in vitro wound healing model. Free from undesired bacterial components, artificial inclusion bodies show promises as delivery agents in regenerative medicine.