Extracellular glutathione peroxidase in human lung epithelial lining fluid and in lung cells

A study was conducted to test the hypothesis that lung cells secrete extracellular glutathione peroxidase (GPx), an antioxidant enzyme, into epithelial lining fluid (ELF). Immunoprecipitation techniques showed that ELF that 57% of ELF GPx activity was due to extracellular GPx and 40% due to cellular GPx. Similar results were observed in primary bronchial epithelial cells, primary alveolar macrophages and two human bronchial epithelial cell lines.