Regeneration of large volumes of bone with biomaterial-based strategies remains a considerable challenge due in part to the need for vascular support of the regenerating tissue.
The complexity of the challenge increases when the biomaterials serve as carriers of cell populations envisioned to promote bone formation. Accordingly, bioreactor strategies have emerged to overcome diffusional limitations associated with static cell culture to enable generation of tissue-engineered constructs for bone repair. A recent article by Gandhi et al. describes the application of a tubular perfusion bioreactor system in which mesenchymal stem cell-laden fibrin beads were cultured for 2 weeks prior to implantation to fill critically-sized rat calvarial defects. The authors report increased bone formation and vascularization in the defects receiving the bioreactor-cultured constructs, relative to empty defects and beads not cultured in the bioreactor system. The authors suggest that the tubular perfusion bioreactor provides a scalable system for the generation of cell-laden beads of uniform size that could be applied easily in surgery to fill large bony defects.
Perfusion Bioreactor Culture of Bone Marrow Stromal Cells Enhances Cranial Defect Regeneration.
Gandhi JK, Kao SW, Roux BM, Rodriguez RA, Tang SJ, Fisher JP, Cheng MH, Brey EM. Plast Reconstr Surg. 2019;143(5):993e-1002e.