At the end of the chronic pulmonary infection, animals were euthanized, and lungs harvested. Lungs were fixed overnight in 10% neutral buffered formalin (Merck, Gibbstown, NJ), then transferred to ethanol, embedded in paraffin, sectioned, and stained with H&E by the Mouse Tumor Model Resources (MTMR) at Roswell Park Comprehensive Cancer Center. Images were taken on an Olympus light microscope equipped with a CCD camera and Spot image analysis software (v25.4; Diagnostics Instruments, Sterling Heights, MI). Lung pathology was evaluated by a pathologist (P.N.B.) who was blinded to treatment groups, as described previously (10 (link)).