Fig. 5.
Proliferation of endothelial cells in response to CLL-cell–derived CM.
HUVECS were cultured in the presence of CM derived from the PMA-stimulated cells of 2 CLL patients (CLL1, CLL7), using rhVEGF protein as a positive control (■). In the same experiment, the CM was preincubated with a neutralizing anti-hVEGF mAb for 1 hour at RT before addition to endothelial cell cultures (▪). After 48 hours, proliferation was assessed by 3H-thymidine incorporation. Proliferation of cells cultured in the medium without CM was considered as 100%; blocking anti-hVEGF mAb had no effect on this proliferation.