Impact of storage solution formulation during refrigerated storage upon chondrocyte viability and cartilage matrix.

Various preservation solutions have been evaluated for longer hypothermic cartilage storage for tissue transplantation; however, the results are mixed. This research was carried out to determine whether phosphate-buffered saline (PBS) or organ preservation solutions would preserve both the extracellular matrix and chondrocytes of articular cartilage better than culture medium during refrigerated storage in the time frame that cartilage is stored for clinical use. Porcine cartilage plugs were stored, without the underlying bone, in culture medium with and without fetal bovine serum (FBS), PBS, Belzer's and Unisol solutions for 1 month at 4°C. Metabolic activity was tested using a resazurin reduction method, and matrix permeability was evaluated by measuring electrical conductivity. Storage in culture medium with 10% FBS was shown to provide good cartilage metabolic function for 7 days, decreasing to about 36% after 1 month of storage. There was no significant difference between samples stored in culture medium with and without FBS after 1 month of storage (p = 0.5005). Refrigerated storage of cartilage in PBS and two different solutions (Belzer's and Unisol) designed for optimal refrigerated tissue and organ storage results in loss of chondrocyte function and retention of matrix permeability. In contrast, the opposite, namely significantly better retention of chondrocyte function and loss of matrix permeability, was observed with culture medium. Future research should be focused on combining retention of chondrocyte function and matrix permeability by storage solution formulation.

Impact of Hypothermia upon Chondrocyte Viability and Cartilage Matrix Permeability after 1 Month of Refrigerated Storage.

BACKGROUND: The purpose of this research was to assess the extracellular matrix and chondrocytes of articular cartilage during refrigerated storage and to determine whether changes could be detected in the time frame that cartilage is stored for clinical use. MATHODS: Porcine cartilage was stored as either bisected femoral heads with bone attached or plugs without the underlying bone in culture medium with fetal bovine serum for 1 month at 4 °C. Metabolic activity was tested using a resazurin reduction method on intact tissue and viable cell recovery after enzymatic tissue digestion at each time point. Cartilage plug permeability was evaluated by measuring electrical conductivity. RESULTS: Storage in culture medium provided good cartilage viability and metabolic function for 7 days; however, significant changes were observed in femoral heads (p < 0.05). All mean chondrocyte assessment values were <30% of fresh controls at 28 days. Cartilage plugs tended to perform better after 7 days of storage than the femoral heads and retained significantly higher metabolic activity (mean = 94.5% vs. 70.5%; p < 0.05). Cartilage plugs demonstrated consistent changes in electrical conductivity after 28 days of storage (p < 0.05). CONCLUSION: Refrigerated storage of cartilage results in both loss of chondrocyte viability and matrix permeability.