We found NE in urine from infected Slpi−/− mice was significantly higher than infected Slpi+/+ mice prior to infection (P = 0.0003), and at both early (3 hpi, P = 0.01) and late time points (1 dpi, P = 0.002; 3 dpi, P = 0.008) (Fig. 5D), suggesting that SLPI may reduce the secretion and/or persistence of NE within the urinary tract even before infection. This evidence concerns the gene SLPI and infection.