MPO and infection: The neutrophil density (Fig 1D–1F) and the levels of neutrophil myeloperoxidase (mpo) and elastase (elane) mRNAs (Fig 1G and 1H) were also higher in lungs from stat3fl/fllysm cre at mice 4 and 8 but not at 14 weeks after infection with M. tuberculosis- compared to controls (Fig 1D–1H and S1A–S1C Fig).