Lung MPO activity, a marker for neutrophil influx, was measured according to the protocols described previously [15 (link),16 (link),17 (link),18 ,19 (link)]. Active Caspase3 activity in lung tissue homogenate was quantified via established protocols [15 (link),16 (link)]. Protein concentration was assessed using the Bradford dye-binding procedure (Bio-Rad, Hercules, CA).