PTEN disruption alleviates the severity of and decreases the mortality associated with neutropenia-related pneumonia. (A) X-ray images were taken using an MX-20 Radiography System (Faxitron X-ray) at the Kresge Imaging Center (Rodent X-ray Unit) at Children's Hospital Boston. Representative X-ray images from untreated (left panel), Cy-treated (middle panel), and E coli–challenged, Cy-treated (right panel) WT or myeloid-specific PTEN KO mice are shown. Mice were anesthetized and images were taken in the postanterior view. The “cloudy areas” in the lungs are indicated. At least 4 mice were examined for each group and essentially the same results were observed. (B) BALF total protein level. Protein accumulated in the inflamed lung was measured using a Bio-Rad protein assay kit. The standard curve was constructed using BSA. (C) Airway resistance (left panel) and dynamic compliance (right panel) were measured in untreated, Cy-treated, and E coli–challenged, Cy-treated mice. For the E coli–challenged, 105 CFU of E coli were instilled intratracheally. Lung mechanics were measured 24 hours later. All data are presented as mean (± SD; n ≥ 4 mice in each group). *P < .05 versus WT. (D,E) Higher survival rates in PTEN KO mice with neutropenia-related pneumonia. Age- and sex-matched WT and PTEN KO mice were pretreated with Cy (250 mg/kg; panel D) or exposed to irradiation (600 cGy) as described in “Methods” and then challenged with 105 live E coli. The survival rates were analyzed using the Kaplan-Meier and log-rank methods. The differences in survival were statistically significant (*P < .01 by log-rank test).
