ABSTRACT
OBJECTIVE: To study the effect of two cytokines, basic fibrolast growth factor(bFGF) and insulin-like growth factor-I(IGF-I), on cell proliferation in chondrocytes of adult rabbits. METHODS: The primary chondrocytes of adult rabbits were harvested and cultured with bFGF and IGF-I at different concentrations, respectively, as well as with the mixture of the two cytokines; the quantity of cultured chondrocytes was detected by MTT assay at the 24th, 48th and 72nd hours; and the final fold increase of different groups was measured by cell count for the 3rd passage; and the proliferation index of the groups was recorded by flowing cytometer on the 14th day. RESULTS: 1. The cultured chondrocytes with either bFGF, IGF-I or their mixture were significantly more than that of control group at the 24th, 48th and 72th hours (P < 0.01). 2. After the 3rd passage, the final folds of proliferation were significantly higher in the groups with cytokines than in the control group (P < 0.01); and the final fold with the mixture of cytokines was significantly higher than that of both IGF-I and bFGF (P < 0.01). 3. The proliferation index was significantly higher in the groups with cytokines than in the control group (P < 0.01); the proliferation index with the mixture of cytokines was significantly higher than that of both IGF-I and bFGF (P < 0.05); besides, proliferation index was higher when cytokine was applied twice than once (P < 0.05); besides, proliferation index was higher when cytokine was applied twice than once (P < 0.05). CONCLUSION: bFGF and IGF-I could promote chondrocytes proliferation of adult rabbits obviously and they are synergistic in cell proliferation.