Figure 4.

Co-infection with L. major leads to a transient immunosuppression. (A) Lymph nodes draining the site of L. major infection were harvested 3 weeks post-infection with LCMV and single cell suspensions stimulated with leishmanial antigen. Supernatants were collected at 72 hr and IFN-γ levels assessed by ELISA. (B) Lymph nodes draining the site of L. major infection were harvested 7 (B) post-infection with LCMV, and single cell suspensions stimulated with leishmanial antigen. Supernatants were collected at 72 hr and IFN-γ, IL-4, IL-10 and IL-17 levels assessed by ELISA. (C and D) Bead purified CD4+ T cells from the spleens of mice 3 weeks after infection with either L. major alone or L. major and LCMV were cultured with infected or uninfected DCs overnight. BFA and monensin were added to cultures for the final 4 hours prior to staining and analysis by flow cytometry. Cells were gated on live, CD45+,CD4+,CD44hi prior to analysis of expression of CD69 (C) and IFNγ (D). Data are representative of 3 independent experiments (A and B; n=3–5 mice per group) or a single experiment (C and D; n=3 mice per group). Error bars represent SEM. NS = not significant