Microfabrication Technology for Vascularized Tissue Engineering

This work describes the application of advanced microfabrication technologies including silicon micromachining and polymer replica molding towards the field of tissue engineering of complex tissues and organs. As a general approach, tissue engineering of skin, bone and cartilage using cell transplantation on biodegradable matrices has achieved great success. However, such techniques encounter difficulties when applied to complex tissues and vital organs. The principal limitation for such applications is the lack of an intrinsic blood supply for the tissue engineered organ, which experiences significant cell death when the tissue thickness is increased above the 1–2 mm range. In this work, the concept of microfabricated scaffolds is introduced, with the goal of producing organ templates with feature resolution of 1 micron, well in excess of that necessary to fashion the capillaries which comprise the microcirculation of the organ. Initial efforts have resulted in high resolution biocompatible polymer scaffolds produced by replica molding from silicon micromachined template wafers. These scaffolds have been successfully seeded with endothelial cells in channels with dimensions as small as the capillaries.