Figure 5

In panel A, cells with features of osteoclasts, as determined by TRAP positivity and ≥3 nuclei/cell (red arrows), were observed after co-cultures of monocytes with autologous CLL B cells for 25 days, without any monocytes pre-activation. Details at high magnification are displayed in the green box. In panel B, monocytes sampled from a healthy donor differentiated toward osteoclastic phenotype after activation with RANKL and MCSF. In panel C, number and the size of osteoclasts, from healthy monocytes pre-activated with MCSF + RANKL, appeared enhanced when conditioned media (CM) of CLL B cells cultures were added. Images are relative to experiments performed with CM from 3 representative CLL cases. In Panel D, histograms depict the average (±SD) percentage of tri-nucleated TRAP⁺ cells counted per field in all different experimental conditions: control CD14⁺ purified monocyte culture; +BE117, +FA35, +FW16, +MG37, +VG34: control monocytes cultured with the addition of the corresponding CM of CLL B cells. Nominal p values are indicated; n.s.: not significant. A minimum of total 3000 cells was counted for each culture condition and experiment.