| The field of tissue engineering is currently limited by the inability to produce small diameter vascular constructs. This includes coronary or peripheral artery bypass grafts as well as pre-vascularized tissue in vitro. While each of these goals offer specific individual challenges, common design requirements such as porosity control, mechanical strength, and biocompatibility suggest that a parallel approach to vascular design is practicable. In this dissertation, we present the design, development, and production of small caliber silk tubes. Two means of production are presented, a dipping method and a gel spinning method, and resultant tubes are characterized in terms of surface morphology, pore size, mechanical strength, protein permeability, and cell response. By controlling the production methods, each of these characteristics may be acutely tuned to meet the precise design requirements of bypass grafts or vascularized tissues. We present the translational aspect of these technologies in vivo using a rat abdominal aorta implantation model as well as in vitro in a pre-vascularized tissue model. These silk tubes, and the techniques used to make them, represent platform technologies for controlling critical microvascular properties, offering substantial improvement over prior art with many tissue engineering applications. |
