Neutrophil MMP-8 and -9 are upregulated in human TB.

<p>(<b>A</b>) Neutrophils were infected with <i>M</i>.<i>tb</i> MOI of 1. MMP-8 secretion was upregulated at 4h. (<b>B</b>) Increasing <i>M</i>.<i>tb</i> MOI caused greater neutrophil MMP-8, analyzed at 4h. Bars represent mean ± s.d. of experiments performed in triplicate and data are representative of a minimum of 2 independent experiments. (<b>C and D</b>) Human TB lung biopsy specimens stained with H&E and anti-neutrophil elastase shows neutrophil infiltration around the cavity wall. Both scale bars represent 5 mm. n = 5. (<b>E and F</b>) Magnified H&E and MMP-8 stains from <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004917#ppat.1004917.g001" target="_blank">Fig 1C</a> inset shows neutrophils immunoreactive for MMP-8 around the cavity wall. Both scale bars represent 50 μm. (<b>G</b>) MMP-9 concentrations increase in a dose-dependent manner after <i>M</i>.<i>tb</i> infection at 4 hours. Bars represent mean ± s.d. of experiments performed in triplicate and data are representative of a minimum of 2 independent experiments. *** <i>P</i><0.001 (<b>H</b>) Biopsy proven <i>M</i>.<i>tb</i> infected human lung specimens were stained for MMP-9 (inset from <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004917#ppat.1004917.g001" target="_blank">Fig 1C</a>). Neutrophils were immunoreactive for MMP-9. Scale bar represents 50 μm. Statistical analysis was performed using two-way ANOVA with Bonferroni post-test or One-way ANOVA with Tukey’s post-test. **<i>P</i><0.01, ***<i>P</i><0.001.