Figure 1.

Combined exposure to RT + IAV decreases survival and intensifies lung injury compared to either RT or IAV alone. A) C57BL/6J, 8-week-old, female mice were exposed to either thoracic RT alone (5, 10, or 12.5 Gy), IAV alone (0.1HAU PR8), or 5 – 12.5 Gy RT followed one week later by inoculation with PR8 (RT + IAV), and survival was followed for 26 weeks. B) Experimental timeline of early and late RT + IAV exposures. Mice were exposed to either 5 Gy RT alone, IAV alone, or 5 Gy RT followed by IAV either 1 week later (early IAV) or 20 weeks later (late IAV) and harvested 26 weeks from the start of the experiment. C) Representative images of lungs from each condition showing regions of pathology where present. Semi-quantitative analysis of lung pathology by D) average pathology score per mouse and by E) the frequency of each score per condition. Bars represent mean ± SEM. Symbols (circles) represent each mouse. n=3–5 mice per condition. Significantly different comparisons are as indicated by brackets. *P<0.05, **P<0.01, ***P<0.001.