Fig. 2.

Osteoclastic phenotype at baseline: TRAP staining. PBMCs from patients with active or non-active RA or healthy controls were differentiated for 21 days with RANKL and M-CSF. 2a: TRAP-staining: Representative micrograph showing TRAP-stained osteoclast cultures, with arrows pointing at positive multinucleated cells (scale bar 50 μm). 2b: Number of TRAP-positive MNCs: the number of multinucleated cells (MNCs) (three or more nuclei) TRAP positive cells per well was evaluated in all groups. All graphs are presented as Box-and-Whisker Plots [median, IQR (25–75)]. **p < 0.01, ***p < 0.001 (comparisons as indicated). 2c: Correlation analysis: Correlation between RA activity (DAS 28) and the number of TRAP-positive MNCs was presented graphically (95% confident bands of the best fit diagonal line are shown).