Enhancement of cartilage extracellular matrix synthesis in Poly(PCL-TMC)urethane scaffolds: a study of oriented dynamic flow in bioreactor.

The development of new technologies to produce three-dimensional and biocompatible scaffolds associated with high-end cell culture techniques have shown to be promising for the regeneration of tissues and organs. Some biomedical devices, as meniscus prosthesis, require high flexibility and tenacity and such features are found in polyurethanes which represent a promising alternative. The Poly(PCL-TMC)urethane here presented, combines the mechanical properties of PCL with the elasticity attributed by TMC and presents great potential as a cellular carrier in cartilage repair. Scanning electron microscopy showed the presence of interconnected pores in the three-dimensional structure of the material. The scaffolds were submitted to proliferation and cell differentiation assays by culturing mesenchymal stem cells in bioreactor. The tests were performed in dynamic flow mode at the rate of 0.4 mL/min. Laser scanning confocal microscopy analysis showed that the flow rate promoted cell growth and cartilage ECM synthesis of aggrecan and type II collagen within the Poly(PCL-TMC)urethane scaffolds. This study demonstrated the applicability of the polymer as a cellular carrier in tissue engineering, as well as the ECM was incremented only when under oriented flow rate stimuli. Therefore, our results may also provide data on how oriented flow rate in dynamic bioreactors culture can influence cell activity towards cartilage ECM synthesis even when specific molecular stimuli are not present. This work addresses new perspectives for future clinical applications in cartilage tissue engineering when the molecular factors resources could be scarce for assorted reasons.