Effect of recombinant human adult T cell leukemia-derived factor on rat lung reperfusion injury

The formation of reactive oxygen species (ROS) is a major factor responsible for reperfusion injury in lungs. Adult T cell leukemia derived factor (ADF), a polypeptide made of 104 amino acids, is induced by a variety of stresses including X-ray, ultraviolet, H2O2, and mitogen. ADF has a reducing activity, which catalyzes the proton transfer between thiol-radical of cystein-containing proteins. Furthermore, ADF has a protective activity of ROS which are formed by xanthine oxidase and other alternative pathways in vitro. Using a rat in vivo model of lung ischemia, we examined the protective effect of recombinant human ADF (rhADF) against ischemia reperfusion injury of the lung. Ischemia, lasting for 75 min, was induced in the left lung of rats at 23 degrees C. The lung was then reperfused. These animals were divided into two groups: group 1 (n = 6, treatment with normal saline) and group 2 (n = 6, treatment with 28 micrograms/g of rhADF). One minute after the beginning of reperfusion, arterial oxygen tension (PaO2) decreased significantly in both groups (p < 0.01), without any significant intergroup difference (55.5 +/- 9.8, 49.8 +/- 8.6 mm Hg, respectively). Twenty minutes after reperfusion, PaO2 was significantly higher (p < 0.05) in group 2 (113.0 +/- 8.1 mm Hg) than in group 1 (72.3 +/- 13.6 mm Hg). The wet/dry weight ratio was significantly higher in group 1 (7.31 +/- 0.54) than in group 2 (5.82 +/- 0.36). Histologically, lung injury tended to be milder in group 2 than in group 1. These results suggest that rhADF has a protective effect against ischemia reperfusion injury of the rat lung.