Our lab is working to engineer vascular grafts derived from naturally-occurring tissues to replace diseased or damaged blood vessels. Arterial replacement is a common treatment for vascular disease; however, the limited availability of the required veins and the significant morbidity and surgical costs associated with their harvest limits their potential. Consequently, the development of viable, small-diameter vascular grafts has been an area of intense focus. My central hypothesis is that using aligned collagen nanofibers – derived from sections of tendon – could offer improved mechanical properties to prosthetic grafts. Collagen is a robust protein common to tissue such as the skin and tendon, with a diameter 1/1000th the thickness of a human hair. Unlike synthetically-manufactured vascular grafts, these tendon-derived devices would still contain biological cues that can guide cellular growth. With the Pew award, I will repurpose tendon fibers in order to create tubular blood vessel grafts. We will then study the host response in a rat model to the tendon-derived grafts – including cell attachment, cell viability, and proliferation. Grafts composed of this material could find many medical therapeutic applications, such as patches for rotator cuff repair, nerve regeneration, or as prosthetic blood vessels to treat vascular disease.