IFN-γ inhibits neutrophil recruitment and IL-17 production after IL-10R blockade.

<p>Mice were infected intradermally with <i>L. major</i> metacyclic promastigotes. Isotype, anti-IL-10R or anti-IFN-γ monoclonal antibodies were administrated at day −1 and twice weekly for 1 week. Cells from the ears were collected, stained and analyzed by flow cytometry. Bar graph showing the frequency of Ly6C⁺, MHCII⁺ and iNOS⁺ expression (A). Numbers on Ly6C⁺ and iNOS⁺ represents percentage of expression on CD11b⁺ Ly6G⁻ gated population. MHCII expression is depicted as the percentage of expression in Ly6C⁺ cells. Ear thickness was measured after 1 week of intradermal inoculation of 2×10⁶<i>L. major</i> metacyclic promastigotes (B) Values represent mean induration in mm (mean ± SEM) of 5 mice per group. Numbers of parasites in ears were quantified using limiting dilution assays (B). Bar graph showing frequency of Ly6G⁺ cells in CD11b⁺ (C). Antigen-specific cytokine release by draining lymph node cells after restimulation with <i>L. major</i> FTAg measured by ELISA (D). Value is the mean ± SEM of 5 mice per group. The data shown are from one experiment and are representative of at least two experiments (*, <i>p</i><0.05). PBMCs from patients with leishmaniasis were cultured with soluble <i>leishmania</i> antigen in the presence or absence of IL-10 or anti-IFN-γ for 4 days. Antigen-specific IL-17 production was analyzed by ELISA (E, F).