RV infection induces a shift in de novo sphingolipid content in lung and blood. (A) Sphingolipid synthesis pathways contributing to the synthesis of ceramide metabolites. Blood and perfused, PBS-washed lungs were collected 24 hours after infection and analyzed by HPLC–mass spectrometry (MS)/MS. (B) Lung de novo synthesis species sphinganine and dihydroceramides C16:0, C18:0, and C18:1. (C) Blood de novo synthesis species sphinganine, sphinganine-1-phosphate, and dihydroceramides C16:0, C18:0, C18:1, C24:0, and C24:1. Data are representative of two independent experiments with 5–6 mice per group. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001 (two-way ANOVA with Tukey’s multiple comparison test). DH = dihydroceramide; S1P = sphinganine-1-phosphate; Sa = sphinganine.