Hepatocyte growth factor gene transfer into the lung and its' therapeutic effect for lung injury and fibrosis

在这项研究中，我们研究了在气管末给药裸质粒DNA进入肺后，机械通气是否可以提高转染效率。将自交系雄性SD大鼠麻醉后，气管内注入p- caggs -荧光素酶或p-CAGGS-lucZ等标记基因。检测潮气量、呼吸频率、PEEP程度、呼吸持续时间等通气参数以获得最大转染效率。基因转移24小时后取肺，用光度计测定荧光素酶的量。与未进行机械通气处理的动物相比，机械通气处理后的动物转染效率更高。X-gal染色检测lucZ基因的定位显示在肺泡内强烈染色。接下来，我们在两种不同的动物模型中检测了基因转移（肝细胞生长因子）的治疗效果。1)在博来霉素诱导的肺纤维化模型中，肝细胞生长因子基因转染肺内并未改善肺纤维化程度。另一方面，被通风的动物死亡率上升。2)分析LPS诱导的急性肺损伤模型中细胞因子水平。IL-10水平较高的小鼠肺损伤程度较轻。因此，我们计划检测IL-10基因转移到lps诱导的肺损伤模型中的作用。

In this study, we have examined whether the transfection efficiency can be improved by mechanical ventilation following end tracheal administration of naked-plasmid DNA into lung. Inbred male SD rats were anesthetized and marker gene such as p-CAGGS-Luciferase or p-CAGGS-lucZ was administered into trachea. Ventilation parameters including tidal volume, respiratory rate, degree of PEEP, and respiratory duration were tested to obtain maximum transfection efficiency. The lungs were harvested after 24 hours after gene transfer, and amount of Luciferase was measured by luminometer. Animals administered followed by mechanical ventilation showed increased transfection efficiency comparing the animals that did not treated by mechanical ventilation. X-gal staining to examine the localization of lucZ gene indicated strong staining within the alveolus.Next, we examined the therapeutic effects of gene transfer (Hepatocyte growth factor) in the two different animal models.1) In the bleomycin induced lung fibrosis model, Hepatocyte growth factor gene transfer into lung did not improve the degree of lung fibrosis. On the other hand, mortality increased in the animals that were ventilated.2) The levels of cytokine were analyzed in the LPS induced acute lung injury model. The animals that have higher level of IL-10 showed less lung injury. Thus, we are planning to examine the effect of IL-10 gene transfer into the LPS-induced lung injury model.