Figure 2. Previous heterologous infection increases leishmanial lesion size with no effect on parasite control.

B6 mice were infected with LCMV Armstrong or left uninfected. After 30 days, mice were infected with L. major and ear thickness was measured weekly (A). Pictures were taken 4 weeks post L. major infection (B). B6 mice were infected with Listeria-OVA or left uninfected and 30 days later boosted again with Listeria-OVA or left uninfected. Thirty days after the boost, all mice were infected with L. major and ear thickness was measure weekly (C). Pictures were taken 5 weeks post L. major infection (D). Infected skin from both groups was taken at various time points post infection and parasite burden was assessed using a limiting dilution assay (E and G). At 4 weeks post infection in the LCMV immune mice, draining lymph nodes were removed and cultured with leishmanial antigen or media alone. After 72 hours, supernatants were removed and analyzed for IFN-γ, IL-4, or IL-17 by ELISA (F). Cells cultured with media alone did not produce any cytokines (data not shown). These data are a compilation of five independent experiments (n = 5–10 mice per group per time point; A, B, E, and F) or representative of two independent experiments (n = 10–16 mice; C, D, and G).