Nogo regulates Plunc expression in vivo and in vitro. (A) Levels of basal gene expression (PLUNC, Tff2, Reg3γ, IL13Rα1, IL13Rα2, and amcase) in WT and Nogo-A/B KO (KO) lungs were determined by qRT-PCR. Data were expressed relative to WT gene expression of 100% (*, P < 0.01). (B) PLUNC gene expression in lungs from control and allergic mice. Data are expressed relative to WT control gene expression of 100% (*, P < 0.01). (C and D) Basal levels of PLUNC protein were analyzed in BAL of WT and Nogo-A/B^−/− mice (C) and in BAL of CCSP-Ng-STG and –DTG mice (D) put on doxycycline water for 3 mo using a PLUNC antibody. Ponceau-stained band at 150 Kb was used as a loading control. (E) NHBECs were treated with a nonsilencing (NS) siRNA or siRNA specifically targeting Nogo-B for 72 h and evaluated for gene expression of Nogo-B, Plunc, TGF-β, and IL4Rα by qRT-PCR. Data were expressed relative to NS gene expression of 100% (*, P < 0.01). Data are expressed as the mean ± SEM. n = 3–6 mice for all groups representative of three experiments with each sample run in triplicate.