Gr-MDSCs and PMNs exert immunosuppressive activity in CML patients.

<p>Arg1 expression (<b>A</b>) and activity (<b>B</b>) were significantly increased in CML PMNs more than autologous Gr-MDSCs isolated from patients at diagnosis. For analysis of western blot the optical density of the bands was measured using Scion Image software. Results represent the means of three independent experiments; error bars denote SEM. (<b>C</b>) The percentage of T cell proliferation was significantly reduced when T cells were cultured with CML Gr-MDSCs (p<0.05) and CML PMNs (p<0.001), while Gr-MDSCs and PMNs from HD did not exert any suppressive activity. Mean frequency of CD3+ CFSE ^dim cells ± SEM from four independent experiments in duplicate is shown.