T helper 2 immunity is enhanced in hypersusceptible CD11c^creIL-4Rα^-/lox mice in response to acute <i>L. major</i> IL81 infection.

<p>Experimental mice were infected subcutaneously with 2×10⁶ stationary phase metacyclic GFP-expressing <i>L. major</i> IL81 promastigotes into the hind footpad (A–D). At week 4 post infection, total CD4⁺ T cells from the draining lymph node were restimulated for 72 hrs with fixed APCs and soluble <i>Leishmania</i> antigen (SLA). The production of IFN-γ (A), IL-4 (B), IL-13 (C) and IL-10 (D) was determined by ELISA. (E–G) Antigen-specific IgG2a (E), IgG1 (F) and total IgE (G) antibody production was quantified from infected sera by ELISA. (H–I) Expression of iNOS and arginase 1 in total footpad cells. Total cells were isolated from footpads at week 4 after infection, surface-stained for CD11b^highMHCII^highCD11c⁻ macrophages followed by intracellular staining for iNOS (H) and arginase 1 (I). GM = geometric means. (J–K) Production of NO and arginase 1 in total footpad cells. Total cells were isolated from footpads at week 4 after infection and stimulated with 10 ng/ml LPS for 72 h. Production of NO was determined in cell supernatants (J) and cell lysates were assayed for arginase 1 production (K). A representative of two individual experiments is shown with mean values ±SEM. Statistical analysis was performed defining differences to IL-4Rα^-/lox mice as significant (*, <i>p</i>≤0.05, **, <i>p</i>≤0.01; ***, <i>p</i>≤0.001).