Figure 4

IL-11-dependent STAT3 activation in CD11b⁺CD14⁺ MDSCs.

(a) PBMCs from blood of healthy donors were stimulated with IL-11 (10 ng/mL) for 10, 30 and 60 min. Total STAT3, phosphorylated STAT3 (pSTAT3) and alpha-tubulin proteins were evaluated by immunoblotting using specific antibodies. The representative data from three independent experiments are indicated. (b) PBMCs were cultured in the presence or absence of IL-11 for 7 days and CD11b⁺CD14⁺ cells were isolated by cell sorting. Total STAT3, pSTAT3 and alpha-tubulin were analysed by immunoblotting. The representative data from three independent experiments are indicated. c, PBMCs were cultured in the presence of STAT3 inhibitor (6-nitrobenzo[b]thiophene-1,1-dioxide, 10 μM) or DMSO with IL-11 and/or GM-CSF for 7 days. Percentages of the induced CD11b⁺CD14⁺ cells were determined by flow cytometry. The means and SDs of the data from three independent experiments are shown. *p < 0.05, compared with control, two-sided Student’s t test.