Traditional treatments for bone injuries have significant limitations. While over one million allogenic and autologous bone grafting procedures are performed each year, significant incidences of medical complications - often involving modest viability, poor integration, or an immune response - still occur. Therefore, the flexibility provided by an in vitro cultured engineered tissue, using cell-seeded scaffolds implanted at the injury site, provides an excellent avenue to repair and replace damaged bone tissue. However, the culture of large volume engineered tissues - particularly cell viability, expansion, proliferation, and differentiation - is limited by current culture techniques. To address this concern, this TR&D focuses on developing 3D printed bioreactors as a dynamic culture system to control cellular microenvironment that promotes cell bioactivity within large engineered constructs.
The Fisher lab at UMD has previously developed a tubular perfusion system (TPS) bioreactor that enables human mesenchymal stem cell expansion, their osteoblastic differentiation, and subsequent formation of boney tissue. Specialized bioreactor chambers are fabricated using 3D printing techniques to engineer variable architecture, controlled flow environments, and spatially located cell populations that enables adequate availability of nutrients, and enable cell-cell interactions, within these large constructs
This TR&D provides a strong foundation and collaborative support to fabricate removable, biodegradable scaffolds of engineered bone tissues that are suitable for in vivo application and to facilitate development of other similarly designed, tissue specific bioreactor systems.