Few commercial bioreactors are available for the culture of three dimensional (3D) tissues. Flexcell's strategy is to provide a commercial bioreactor allowing ease of operation to produce molded 3D tissue constructs in cell- populated matrix gels of variable geometries with controlled nutrient perfusion and mechanical stimulation. This design is based on a validated, pressure-operated platform technology with a scaled-up, TissueTrain(tm) 3D culture system, to allow individual research teams to investigate "best" techniques and methods to develop and integrate specific tissues. Long-term goals of the project include refining and automating the bioreactor to develop tissue replacements for regenerative medicine. Tissue replacements will be fabricated from template molds and anchors allowing host integration. The Phase II device will have additional sensors that can monitor the development of the bioartificial tissue, including O2, CO2, pH, ionic strength, specific metabolites, construct size, shape and density and even contamination with bacteria or viruses. Specific Aims include: 1. use finite element modeling of key design features to predict effects of increased contact surface areas at tissue anchor ends in each bioreactor chamber, diffusion constraints as a tissue is scaled-up, as well as the strains generated with in the construct as force is applied to mechanicaly condition the nascent tissue. 2. develop inerative designs based on results of FEA simulations for a scaled-up 3D tissue bioreactor and tissue anchor/integration system built on Flexcell's flexible bottom culture plate (TissueTrain(tm)) platform using tissue molding for fabrication and mechanical loading to condition the constructs. The anchor end designs will include more involved 3D embodiments that allow increased bonding and host integration geometries for cells and matrix. 3. fabricate examples of linear (anterior cruciate ligament) and circular (dermal skin construct) 3D constructs using ATCC cell lines and monitor limited outcome parameters such as matrix expression, remodeling of the gel matrix and biomechanical strength. Ligament cells and dermal fibroblasts will be used to fabricate linear and circular 3D cell- gel constructs that can be monitored in situ in the bioreactor. The research version of this bioreactor is already commercially available by Flexcell International Corp. Expansion to a larger bioreactor chamber will allow biomedical researchers to develop better strategies for growth and testing of scaled up tissues for use in vivo in numerous connective tissue applications
