Figure 5.

Sections of C57Bl/6 (A) and cathelin-related antimicrobial peptide (CRAMP)–deficient bladders (B) 6 and 24 hours after infection were stained with hematoxylin and eosin for morphological analysis. Whole bladder sections (left panels; scale bar, 400 µm) show substantially increased edema in wild-type mice at both time points. Acute cystitis is evident in both host strains 6 hours after infection (right panels; scale bar, 40 µm). However, at 24 hours after infection, the infected wild-type bladder remains edematous and completely exfoliated, while CRAMP-deficient bladders reflect resolved inflammatory changes and recovery of the superficial epithelial layer. C, Expression of 6 representative cytokines is significantly lower in CRAMP-deficient bladder homogenates 6 hours after infection (*P < .05 and **P < .01). D, At 24 hours after infection, only granulocyte macrophage colony-stimulating factor expression was significantly lower in CRAMP-deficient mice, among 23 cytokines measured (*P = .032; data not shown). E and F, Whole-bladder myeloperoxidase (MPO) activity is significantly lower in CRAMP-deficient mice 6 hours after infection (E); this difference was no longer significant at 24 hours after infection (F). G, Densitometric analysis of bladder UPIIIa expression indicates more rapid epithelial recovery in CRAMP-deficient mice (white bars) than in wild-type mice (black bars; *P < .05 and **P < .01). Mean and standard errors of the mean are indicated in panels C–G. Abbreviations: G-CSF, granulocyte colony-stimulating factor; IL-1β, interleukin 1β; IL-6, interleukin 6; IL-17, interleukin 17; KC, keratinocyte chemoattractant; MCP-1, monocyte chemoattractant protein 1; NS, not significant.