FIG. 1.
Creation of hypertrophic chondrocyte constructs through application of variable flow rates. Bone cores were extracted from juvenile bovine wrists, decellularized, and sized to 4 mm diameter × 5 mm height. Human BMSCs were expanded and seeded into the decellularized bone cores (2.25 × 106 cells/construct). Seeded constructs were then placed into previously validated perfusion bioreactors21,31 and differentiated for 2 weeks in the chondrogenic medium, then matured to hypertrophic chondrocytes over an additional 3 weeks. Flow rates were determined by the tubing diameter, and flow rates approximating 0, 100, 400, and 1200 μm/s were chosen for experimentation. At the end of 5 weeks of culture, constructs were implanted into a 5 mm, critical-size defect made in the right femur of RNU nude male rats. Construct regeneration occurred for 8 weeks in vivo before harvest and construct evaluation. BMSC, bone marrow-derived stem cell; RNU, Rowett Nude; SD, standard deviation. Color images available online at www.liebertpub.com/tea