Prolonged storage of osteochondral allografts: does the addition of fetal bovine serum improve chondrocyte viability?

Osteochondral plugs were harvested from eight fresh human femoral condyles within 96 hours of donor death. The plugs were either stored in a serum-free media containing glucose, salts, and amino acids or 10% fetal bovine serum at 4 degrees C. After 28 days of storage, the osteochondral plugs were analyzed for chondrocyte viability and viable cell density using confocal microscopy, proteoglycan synthesis by (35)SO4 incorporation, and glycosaminoglycan content. Chondrocyte viability and cell density were significantly lower in grafts stored in serum-free media compared to fetal bovine serum, 27% versus 68% (P < .001) and 3250 cells/mm3 versus 8960 cells/mm3, respectively (P < .001). The metabolic activity determined by proteoglycan synthesis was significantly better in the specimens stored in fetal bovine serum (P < .01). No significant difference was detected between the glycosaminoglycan content in any of the specimens. These data suggest that the quality of osteochondral allografts as measured by chondrocyte viability, viable cell density, and proteoglycan synthesis is superior after storage in fetal bovine serum versus serum-free media. These results must be taken cautiously, however, as the clinical ramifications of storage in fetal bovine serum, including potential infectious disease transmission risks and immunogenic factors, have yet to be studied.