Mechanisms of Response to Ozone Exposure: The Role of Mast Cells in Mice

Dr. Kleeberger and colleagues at Johns Hopkins University compared ozone-induced inflammation, epithelial cell injury, and epithelial cell proliferation (a marker of cell injury) in three types of mice: mice with a normal content of mast cells, mutant mice without mast cells, and mutant mice whose mast cells were repleted by a bone marrow transplant from normal mice. Each group of mice was exposed to clean air or to ozone for varying lengths of time. To determine whether the effects of prolonged ozone exposure reversed, the investigators exposed a separate set of mice from each group to ozone for 90 days and allowed them to breathe clean air for 35 days before they measured inflammation, cell injury, and cell proliferation.