aDC depletion at 48 h p.i. results in decreased pulmonary IL-15 mRNA and protein expression. Groups of BALB/c mice were infected with a sublethal dose of IAV with or without aDC depletion as in Fig. 1. (A) On day 6 p.i., lungs were removed and analyzed using qRT-PCR analysis for IL-15 expression. Results were normalized to GAPDH expression, and then to expression of IL-15 mRNA by naive lungs to calculate the ΔΔCt. Data are pooled from two separate experiments and represent means ± SEM (n = 3–6 mice/group). (B) On day 6 p.i., lung homogenates from groups of naive, control, and aDC-depleted mice were analyzed for IL-15 protein expression by ELISA as described in Materials and methods. The dashed line represents the limit of detection of the assay. Data are representative of four separate experiments and represent means ± SEM (n = 5 mice/group). ND, not detected.