Bioreactor improves the growth and viability of chondrocytes in the knitted poly-L,D-lactide scaffold

In the present study bovine chondrocytes were cultured in two different environments (static flasks and bioreactor) in knitted poly-L,D-lactide (PLDLA) scaffolds up to 4 weeks. Chondrocyte viability was assessed by employing cell viability fluorescence markers. The cells were visualized using confocal laser scanning microscopy and scanning electron microscopy. The mechanical properties and uronic acid contents of the scaffolds were tested. Our results showed that cultivation in a bioreactor improved the growth and viability of the chondrocytes in the PLDLA scaffolds. Cells were observed both on and in between the fibrils of scaffold. Furthermore, chondrocytes cultured in the bioreactor, regained their original round phenotypes, whereas those in the static flask culture were flattened in shape. Confocal microscopy revealed that chondrocytes from the bioreactor were attached on both sides of the scaffold and sustained viability better during the culture period. Uronic acid contents of the scaffolds, cultured in bioreactor, were significantly higher than in those cultured in static flasks for 4 weeks. In summary, our data suggests that the bioreactor is superior over the static flask culture when culturing chondrocytes in knitted PLDLA scaffold.