Osteoarthritis (OA) is the leading cause of chronic disability in the United States. A clinical goal in the treatment and prevention of OA is to develop replacement cartilage using tissue engineering (TE) technologies. Although TE cartilage presently lacks the mechanical stability of native cartilage, studies have demonstrated that mechanical stability can be enhanced with specific chemical and mechanical stimuli. To speed the discovery of optimal stimulation protocols, research platforms need to be available that enable fast, clear and reliable communication of functional outcomes (i.e material properties). Towards this goal, we introduce a six-chamber bioreactor that combines the efficiency of batch testing with the accuracy normally reserved for dedicated single-specimen material test systems. This system is therefore capable of mapping functional development of six individual specimens exposed to highly-specific mechanical stimulation protocols. To remain cost-effective and portable, the bioreactor leverages system redundancies to eliminate hardware.
The specific aim of this study is to test the bioreactor's capacity to deliver accurate mechanical stimulations and material property evaluations in all six test chambers. The effect of loading conditions and specimen geometry on accurate mechanical stimulation will be quantified using external sensors. The viscoelastic material properties of soft TE scaffolds and stiff cartilage plugs will be characterized in both the six-chamber bioreactor and a conventional single-stage testing device. Results between the bioreactor and the model testing system will be statistically compared. If validation of the bioreactor is successful, we envision this product will provide an economical and reliable research platform that fosters TE technology transfer.
Tissue engineering of articular cartilage presents a promising strategy for treatment of osteoarthritis, a debilitating and prevalent disease. Cartilage engineering techniques, however, are currently unable to reproduce the mechanical properties critical to native cartilage, thus impeding the transfer of TE technology to patient care. A bioreactor is therefore proposed to facilitate the rapid discovery of mechanical conditions that promote the synthesis of mechanically viable tissue.
|Lujan, Trevor J; Wirtz, Kyle M; Bahney, Chelsea S et al. (2011) A novel bioreactor for the dynamic stimulation and mechanical evaluation of multiple tissue-engineered constructs. Tissue Eng Part C Methods 17:367-74|