intratracheal delivery of airway epithelial cells in mice and pigs. Am

lar therapy via direct intratracheal delivery has gained interest as a novel therapeutic strategy for treating various pulmonary diseases including cystic fibrosis lung disease. However, concerns such as insufficient cell engraftment in lungs and lack of large animal model data remain to be resolved. This study aimed to establish a simple method for evaluating cell retention in lungs and to develop repro-ducible approaches for efficient cell delivery into mouse and pig lungs. Human lung epithelial cells including normal human bronchial/ tracheal epithelial (NHBE) cells and human lung epithelial cell line A549 were infected with pSicoR-green fluorescent protein (GFP) lentivirus. GFP-labeled NHBE cells were delivered via a modified intratracheal cell instillation method into the lungs of C57BL/6J mice. Two days following cell delivery, GFP ELISA-based assay revealed a substantial cell-retention efficiency (10.48 2.86%, n 7) in mouse lungs preinjured with 2 % polidocanol. When GFP-labele