Altered lineage commitment of bone marrow mesenchymal stem cells in idiopathic osteonecrosis of the femoral head

Figure 1 Proliferation of mesenchymal stem cells assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Absorbance at 570 nm was measured in mesenchymal stem cells derived from patients with osteonecrosis of the femoral head (black line) and osteoarthritis of the hip (gray line) at different culture time points (days 1, 3, 5, and 7). Cells were plated in quadruplicate at 200 cells, 400 cells, 800 cells, or 1000 cells per well, as shown in the lower panels, and a global analysis averaging across all seeding densities is presented in the upper panel. Values represent estimated marginal means with 95% confidence intervals obtained from generalized estimating equation models with patient identifier as clustering variable and an exchangeable correlation structure. Asterisks denote significant differences between groups at the corresponding time point (P < 0.05). Biological replicates: Osteoarthritis n = 10, osteonecrosis of the femoral head n = 10. CI: Confidence interval; EMMs: Estimated marginal means; OA: Osteoarthritis; ONFH: Osteonecrosis of the femoral head; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.