Every year, over 6 million bone fractures occur in the United States. Many are large load-bearing bone defects, such as long bone injuries that require bone grafts to aid skeletal repair. This significant clinical problem is often limited by the high clinical failure rates of allografts. Tissue engineering holds great promise for improving the treatment of skeletal defects. However, most tissue engineering approaches to treating large load-bearing bone defects have been limited by (1) a lack of vascularity, (2) the difficulty of mimicking the complex cell-matrix and cell-cell interactions, (3) the difficulty of uniformly seeding cells throughout the scaffold and (4) insufficient scaffold mechanical strength.

To significantly advance the tissue engineering of bone, we aim to integrate nano-, micro- and macro-scale tissue engineering technologies with biomimetic beta-tricalcium phosphate (beta-TCP) graded scaffolds to generate microengineered osteon-containing load-bearing tissue constructs. It is expected that this project will generate mineralized vascular tissues with biomimetic architecture, enhanced functionality, and comparable mechanical properties to bone that may ultimately provide improved tissue engineered constructs for skeletal tissue repair.

In collaboration with CECT, this project aims to fabricate cortical bone (osteons) through microfabrication and microengineering approaches to generate osteoblast-laden, patterned collagen gels containing arrays of endothelialized channels. In order to develop biomimetic tissues, these osteons will be incorporated within bone-like beta-TCP graded scaffolds and their ability to accelerate bone regeneration and repair in vivo will be assessed.