PTEN在支气管哮喘大鼠气道炎症中的作用

目的 探讨PTEN在支气管哮喘(简称哮喘)大鼠气道炎症中的作用.方法 20只SPF级雄性SD大鼠随机分为2组,对照组和哮喘组.以卵清白蛋白致敏激发法复制大鼠哮喘模型,每只大鼠左肺留取肺组织,右肺进行支气管肺泡灌洗并留取支气管肺泡灌洗液(BALF).对BALF进行细胞分类计数;应用双抗体夹心酶联免疫吸附试验(Sandwich ELISA)法测定BALF中IL-4、IL-12浓度;采用免疫组织化学法和Western blot法测定PTEN蛋白的表达和量的变化.结果 ①BALF IL-4的浓度哮喘组显著高于对照组,BALF中IL-12的浓度哮喘组显著低于对照组(P值均＜0.01);②免疫组织化学显示PTEN蛋白主要表达细胞是支气管上皮细胞,Western blot法显示哮喘组支气管PTEN蛋白的表达显著低于对照组(P＜0.01);③支气管上皮细胞PTEN蛋白表达量分别与BALF中的IL-4浓度呈显著负相关,与BALF中的IL-12浓度呈显著正相关.结论 哮喘大鼠PTEN蛋白表达明显减少,它能减少Th2因子的表达,可能与哮喘大鼠气道炎症中Th1/Th2平衡密切相关.

Effect of PTEN on airway inflammation in a rat bronchial asthma model

Objective To study the effect of PTEN on airway inflammation in a rat bronchial asthma(asthma)model.Methods Twenty Male Sprague-Dawley rats were radomly divided into control group and asthma group.The lung tissue was sampled from the left lung.Bronchoalveolar lavage fluid (BALF)was collected from the right lung.The concentration of the IL-4 and IL-12 in BALF were measured by Sandwich ELISA.The PTEN protein was observed by the technique of immunohistochemistry and the level of PTEN in lung homogenate was measured by Western blot.Results ①The concentration of IL-4 in BALF of asthma group was significantly higher than control group.The concentration of IL-12 in BALF of asthma group was significantly less than asthma group(both P＜0.01).②PTEN protein was observed in the epthe lial cells of bronchus，and the level of PTEN protein in lung homogenate of asthma group was signigicantly lower than that in control group(P＜0.01).③There were significantly positive correlations between the expression of PTEN protein in lung homogenate and the level of IL-12 in BALF.There were significantly negative correlations between the expression of PTEN protein in lung homogenate and the level of IL-4 in BALF.Conclusions The expression of PTEN protein is decreased in the epithelial cell of asthma rats，it desreases the expression of Th2 cytokine and has correlation with the balance of Th1/Th2.