ABSTRACT
AIM: To investigate the role of transferrin/transferrin receptor system in transferrin-bound Yb 2 (Yb 2Tf) uptake by U-87 MG cells and the effect of transferrin-bound and -free Yb 2 on proliferation of U-87 MG cells. METHODS: Cell culture and ICP-MS measurement of Yb 2. RESULTS: Yb 2Tf uptake by U-87 MG cells increased with the concentrations of Yb 2Tf, and reached saturation as the concentration in the incubation medium was raised to about 2 ?mol/L. Also, Yb 2 uptake by the cells increased with increase of the mole ratio (Yb 2: apoTf), reaching a maximum at 1.5 mole ratio. Yb 2Tf in 0.4 ?mol/L significantly inhibited proliferation of U-87 MG cells, however, 10 ?mol/L Yb 3+ had no significant effect on proliferation of the cells. CONCLUSION: The uptake of Yb 2 by U-87 MG cells might be mediated by transferrin/transferrin receptor system. Transferrin-bound but not transferrin-free Yb 2 could significantly inhibit proliferation of U-87 MG cells.