Objective:To investigate the effect of transtracheal transfering the adenovirus-mediated human interleukin 10 (hIL-10)gene on lung ischemia-reperfusion injury(IRI),and posttransplant lung function in SD rat lungs. Methods:Thirty-six male SD rats were divided into 3 groups randomly:blank control group,empty vector-control group and gene transfer group. The donors of three groups received 0.5 ml of normal saline,5×109 PFU of Ad-5 or 5×109 PFU of Ad-5-hIL-10,respectively. After 24 h of in vivo transfection,lungs were harvested and stored in low-potassium dextran solution(LPDG) at 4℃ for 18 h. Then the left lung orthotopic transplantation was performed. After 4 h of reperfusion,arterial blood gas analysis and wet-to-dry(W/D) weight ratios were determined,superoxide dismutase (SOD) activity,malondialdehyde (MDA) contents and myeloperoxidase (MPO) activity were detected. Tumor necrosis factor-α(TNF-α) and interferon-γ(IFN-γ) were measured in graft tissue by ELISA. Besides,hIL-10 was detected by immunohistochemistry. Graft pathohistological changes were examined under a light microscope. Results:Empty vector and blank control groups showed a significant lung ischemia-reperfusion injury(IRI),while gene transfer group’s lung IRI reduced significantly. The lung tissue edema,interstitial inflammation and exudation in gene transfer group were obviously reduced. Expression of hIL-10 gene was obviously incrdased when detected by immunohistochemistry (IHC). Partial pressure of oxygen (PaO2) levels in the gene transfer group were higher than in empty vector and blank vector groups (P < 0.01),respectively. W/D ratios were reduced in hIL-10 lungs (P < 0.05) compared with the other groups. MDA contents and MPO activity were reduced in tissue of the gene transfer group(P < 0.01). But the activity of SOD was increased significantly (P < 0.01). TNF-α and IFN-γ were reduced in tissue of the gene transfer group(P < 0.01) measured by ELISA. Conclusion:Transtracheal adenovirus mediated gene transfection of hIL-10 can obviously lighten IRI after lung transplantation and improve early lung function effectively after lung transplantation.