Interleukin-4 (IL-4), gamma-interferon (IFN-γ), interleukin-5 (IL-5), interleukin-13 (IL-13), interleukin-23 (IL-23), interleukin-27 (IL-27), transforming growth factor-beta (TGF-β), interleukin-6 (IL-6, R&D), and tumor necrosis factor-α (TNF-α Peprotech) were used at a final concentration of 20 ng ml−1, for 24 h (unless otherwise stated). ATP was used at 1 mM for 5–30 min. In all experiments, pharmacological inhibitors were added to the cell medium, composed by DMEM supplemented with vesicle-depleted serum, 1 h before the addition of cytokines and 24 h before that of ATP, and maintained throughout the treatments: in this way the effects of the inhibitors on cytokine and ATP treatments can be compared.