Maturational growth of self-assembled, functional menisci as a result of TGF-β1 and enzymatic chondroitinase-ABC stimulation

Replacement of the knee meniscus requires a material possessing adequate geometrical and biomechanical properties. Meniscal tissue engineering attempts have been unable to produce tissue with collagen content and biomechanical properties, particularly tensile properties, mimicking native menisci. In an effort to obtain the geometric properties and the maturational growth necessary for the recapitulation of biochemical and, thus, biomechanical properties, a scaffoldless cell-based system, the self-assembly process, was used in conjunction with the catabolic enzyme chondroitinase-ABC and TGF-β1. We show that combinations of these agents resulted in maturational growth as evidenced by synergistic enhancement of the radial tensile modulus by 5-fold and the compressive relaxation modulus by 68%, and additive increases of the compressive instantaneous modulus by 136% and Col/WW by 196%. This study shows that tissue engineering can produce a biomaterial that is on par with the biochemical and biomechanical properties of native menisci.