This Phase II SBIR application is responsive to Program Announcement PA-09- 113, "Manufacturing Processes of Medical, Dental and Biological Technologies". This PA solicits work on "technology for the manufacture of implantable devices and materials, prosthetic organs, and artificial tissues". Humacyte has developed a novel vascular graft that has shown excellent function in large animal models. The graft is made by culturing allogeneic human smooth muscle cells in a bioreactor to produce an engineered vascular tissue. This engineered tissue is then carefully decellularized, so as to remove the immunogenic cellular components, while retaining the collagenous extracellular matrix. These grafts have the advantage of being non-living, and hence can be stored on the shelf for periods of up to 9 months. Vascular dialysis grafts that are 6 mm in diameter function well in a baboon model of arterio-venous grafting, and are resistant to two important failure modes of synthetic dialysis grafts: thrombosis and intimal hyperplasia. This SBIR application is directed at scaling the manufacture of this exciting and novel engineered tissue. In our Phase I proposal, our aim was the construction and testing of a prototype, disposable vascular graft bioreactor. In this Phase II proposal, we will build on our successful Phase I work, and we will refine and build a scaled-up manufacturing system that will enable cost-effective production of our unique, off-the-shelf vascular graft for dialysis access. This pilot scaled system will also be applicable to the manufacture of other types of engineered tissues, and hence will benefit the regenerative medicine field as a whole. We will hone the single-use bioreactor system and in parallel, we will define rapidly consumed components of culture medium and develop a strategy to supplement those limiting factors, thereby reducing overall culture medium usage. Together, these strategies will allow us to produce a scaled, economical manufacturing system. Dialysis grafts produced in the scaled system will be assessed using standard assays for graft biochemical extracellular matrix composition, cell viability, mechanical integrity, as well as graft in vivo function in a primate model. The results of these studies will contribute to the submission of an IND application to the FDA.
This Phase II SBIR application addresses a critical need in regenerative medicine: the development of scaled manufacturing systems that produce engineered tissues in a reproducible and economical fashion.