[Effects of various growth factors on human mandibular condylar cartilage cell proliferation]

To investigate the effects of transforming growth factor-beta 1 (TGF-beta 1) insulin-like growth factor I (IGF-I) and basic fibroblast growth factor(bFGF) on human mandibular condylar cartilage (MCC) cell proliferation.

Isolated human MCC cells were cultured in DMEM supplemented with 10% newborn calf serum(NCS). The second passages were used in order to avoid chondrocyte dedifferentiation. Cells were seeded at 2 x 10(4)/well on 96-well plate. After synchronization, medium was replaced by DMEM containing 0.4% NCS or 10% NCS with various growth factors, concentrations and combinations. Dose-response and time-course were studied by MTT colorimetric method.

In 0.4% serum containing medium, bFGF stimulated the proliferation moderately, whereas TGF-beta 1 and IGF-I had less effect. In 10% NCS condition, all three growth factors had mitogenic effect and acted dose-dependently. The effects were significant after three days. Among them, bFGF was a potent mitogen(increased by 65%), IGF-I the next(24%). The effect of TGF-beta 1 (13%) might be mediated by some other factors in the serum. The synergetic effects were achieved when they were used in combination.

It is suggested that optimal combination of growth factors can promote the proliferation of MCC cells significantly, this might be an ideal way in dealing with cartilage damage during pathogenesis.