Pulmonary contusion induces alveolar type 2 epithelial cell apoptosis: role of alveolar macrophages and neutrophils.

Alveolar type 2 (AT-2) cell apoptosis is an important mechanism during lung inflammation, lung injury, and regeneration. Blunt chest trauma has been shown to activate inflammatory cells such as alveolar macrophages (AMs) or neutrophils (polymorphonuclear granulocytes [PMNs]), resulting in an inflammatory response. The present study was performed to determine the capacity of different components/cells of the alveolar compartment (AMs, PMNs, or bronchoalveolar lavage [BAL] fluids) to induce apoptosis in AT-2 cells following blunt chest trauma.