Combinatorial effects of inorganic ions on adhesion and proliferation of osteoblast-like cells.

Combinatorial effects of three ions, namely silicate (Si), calcium (Ca), and magnesium (Mg) ions, on the adhesion and proliferation of MC3T3-E1 mouse osteoblast-like cells were evaluated. The cells were cultured in single-, dual-, or triple-ion-conditioned culture media with systematically changed ion concentrations. The ranges of Si, Ca, and Mg ion concentrations were set as 10-70, 80-400, and 25-500 ppm, respectively. The numbers of adherent live cells were measured after culturing for 3 h and for 1, 3, and 5 days to examine cell adhesion and proliferation, respectively. Mg ions predominantly enhanced cell adhesion in both the dual-ion (xSi-zMg and yCa-zMg) and triple-ion (xSi-yCa-zMg) systems but had no effect when they acted individually in the single-ion system. Conversely, Si ions predominantly enhanced cell proliferation in most single- and triple-ion-conditioned media. Evaluation of the combinatorial effects of the three ions on cell adhesion and proliferation revealed that the dual- and triple-ion-conditioned media mainly conferred synergistic effects on adhesion but antagonistic effects on proliferation.