Cell viability determination.

<p>(<b>A</b>) MTT assays on the bone marrow cells. Mouse bone marrow cells were isolated and exposed to FTY720 with different concentrations for 48 h. Cytotoxicity was indicated by the ratio of OD_FTY720 to OD_control. Data are shown as mean ± SEM. *<i>P</i><0.05, n = 3. (<b>B</b>) MTT assays on BMDCs. Day 6 BMDCs were treated with FTY720 at concentrations of 0, 0.1, 0.5 and 1.0 µM for 48 h. Data are shown as mean ± SEM. *<i>P</i><0.05, n = 3. (<b>C</b>) Apoptosis assays on BMDCs. The cell death rates of BMDCs was determined by Annexin V-FITC and PI staining flow cytometry. Cells were treated with FTY720 for 48 h at concentrations ranged from 0.5 to 10 µM.