<i>P. aeruginosa</i>, but not exogenous LL-37, induces pulmonary cytokine responses.

<p>Wild type C57Bl/6 mice were inoculated with 3×10⁷ cfu of <i>P. aeruginosa</i> PAO1 and 10 µg LL-37 peptide or PBS by intranasal delivery. At 6 hours (a–e) or 24 hours (b–j) after inoculation, mice were culled and their lungs were lavaged. BALF was centrifuged to remove cells and levels of TNF (a, f), IL-6 (b, g), MIP-2 (c, h), KC (d, i) and MCP-1 (e, j) were determined. Data show Tukey box and whiskers plots for n≥9 animals per condition. Analyses were conducted using the Mann Whitney test.</p

Exogenous LL-37 enhances pulmonary clearance of <i>P. aeruginosa</i> in cathelicidin-deficient mice.

<p><i>Camp−/−</i> mice were inoculated with 3×10⁷ cfu of <i>P. aeruginosa</i> PAO1 or PBS and 10 µg LL-37 peptide or PBS by intranasal delivery. At 6 or 24 hours after inoculation mice were re-weighed and culled, and their lungs were lavaged before homogenisation. BALF and lung homogenates were serially diluted, plated and incubated overnight at 37°C before bacterial colonies were counted and corrected for volume. Mean PAO1 cfu +/− SEM in the lung homogenate (a & c) or BALF (b & d) for infected animals (n≥6 per condition at 6 hours and n≥10 per condition at 24 hours) are displayed. No bacteria were detected in samples from uninfected mice. For statistical analyses bacterial counts were normalised by logarithmic transformation. Analyses were conducted using 2 way ANOVA with Bonferroni's post tests; ** p<0.01, *** p<0.001.</p

Exogenous LL-37 promotes an early neutrophil response to <i>P. aeruginosa</i>.

<p>Wild type C57Bl/6 mice were inoculated with 3×10⁷ cfu of <i>P. aeruginosa</i> PAO1 or PBS and 10 µg LL-37 peptide or PBS by intranasal delivery. At 6 hours (a, b & e) or 24 hours (c, d & f) after inoculation mice were culled and their lungs were lavaged. BALF was cytocentrifuged and differential counts were conducted for neutrophils (a–d) and monocytes (e & f). Data show Tukey box and whiskers plots for infected (a, c, e & f) (n≥9 per condition) and uninfected (b & d) animals (n≥5 per condition). Analyses were conducted using the Mann Whitney test; * p<0.05. ND denotes “not detected”.</p

<i>P. aeruginosa</i>, but not cathelicidin sufficiency, induces pulmonary cytokine responses.

<p><i>Camp−/−</i> mice and wild type controls were inoculated with 3×10⁷ cfu of <i>P. aeruginosa</i> PAO1 by intranasal delivery. At 6 hours (a–e) or 24 hours (b–j) after inoculation, mice were culled and their lungs were lavaged. BALF was centrifuged to remove cells and levels of TNF (a, f), IL-6 (b, g), MIP-2 (c, h), KC (d, i) and MCP-1 (e, j) were determined. Data show Tukey box and whiskers plots for n≥8 animals per condition. Analyses were conducted using the Mann Whitney test.</p

Cathelicidin-deficient mice display impaired late neutrophil responses to <i>P. aeruginosa</i>.

<p><i>Camp−/−</i> mice and wild type controls were inoculated with 3×10⁷ cfu of <i>P. aeruginosa</i> PAO1 by intranasal delivery. At 6 hours (a & b) or 24 hours (c & d) after inoculation mice were culled and their lungs were lavaged. BALF was cytocentrifuged and differential counts were conducted for neutrophils (a & c) and monocytes (b & d). Data show Tukey box and whiskers plots for n≥8 animals per condition. Analyses were conducted using the Mann Whitney test; * p<0.05.</p