CLL-CM promotes the migration and proliferation of the MSCs. (A) Bar graphs showing MSC migration in response to CLL-CM or control serum-free AIM-V medium. MSCs from 16 different patients were labeled with calcein AM, and the fluorescence intensity of migrated cells measured with a fluorescent plate reader. The percentage of MSC migration was calculated by the fluorescence intensity of the migrated MSC divided by the fluorescence intensity of the same number of MSC seeded in the 24 wells directly as positive control (n = 16, P < .001). (B) The bar graph represents MSC proliferation in response to CLL-CM or control serum-free AIM-V medium (n = 13, P < .001). MSC from 13 different patients were used in this study. (C) Representative photographs of CLL MSC cultured with either AIM-V or CLL-CM for 1 month followed by staining with Coomassie blue for CFU assay. (D) The number of MSC CFU cultured with either CLL-CM or control AIM-V (n = 16, P < .001) is shown in the bar graph. MSCs from 16 different patients were used in the experiments shown in panels A and D. The MSCs used in panels C and D were from patient sources different from the MSCs used in panel B.