Figure 5.

eIF-4E activation is required for T helper type 17 (Th17) generation and interleukin-17 (IL-17) release in human CD4⁺ naive cells: (a) FACS-sorted naive CD4⁺ T cells were stimulated for 20 min with PMA/ionomycin and then checked for p38 phosphorylation and eIF-4E expression by Western blot. One experiment out of three is shown. Tubulin was used as loading control. (b) FACS-sorted naive T cells were polarized into Th17 in the presence or absence of the MAPK interacting protein kinases (MNKs) inhibitor. After 5 days the frequency of vital cells (upper panels) and of IL-17-releasing cells (lower panels) was assessed by flow cytometry. Plots from a representative experiment out of three are shown. Graphs represent the frequency of live cells (upper graph) and IL-17⁺ cells (lower graph) gated on CD4⁺ lymphocytes. Error bar represents the SE from the mean of three distinct experiments. (c) CD4⁺ naive T cells were polarized into Th17 lymphocytes in the presence of different dilutions of the MNK inhibitor. (d) Graph represents the levels of IL-17 in the supernatants with different concentrations of iMNK. *P < 0·05.