摘要
目的观察哮喘豚鼠支气管肺泡灌洗液(bronchoalveolar lavage f luid,BALF)中不同密度嗜酸细胞(Eos)上白介素-5受体α(IL-5Rα)、IL-3Rα、粒细胞-巨噬细胞集落刺激因子受体α(GM-CSFRα)及共同β链受体(βcR)mRNA表达及雷公藤甲素(TP)对它们的影响,探讨TP促进哮喘Eos凋亡的机制。方法健康豚鼠18只随机分为正常组、哮喘组、TP组。以卵蛋白 致敏激发制作豚鼠哮喘模型,分离BALF中的低密度Eos(HEos)及正常密度Eos(NEos),TUNEL法检测细胞凋亡,原位杂交检测各受体mRNA表达,RT-PCR法检测Eos IL-5Rα、IL-3Rα相对含量。结果哮喘豚鼠Eos凋亡明显减少,而细胞数明显高于正常组。用TP 24 h后不同密度Eos数量明显低于哮喘组(P<0.01),以HEos下降为明显(P<0.05);TP组Eos凋亡明显高于哮喘组(P<0.01)。哮喘豚鼠Eos表达α受体mRNA明显低于正常组,而βcR表达明显增高;TP处 理组Eos各α受体mRNA表达均明显增加,βcR表达明显下降。RT-PCR检测显示,TP组IL-5R α、IL-3Rα mRNA显著增加。结论哮喘Eos存在凋亡抑制;TP可通过促 进IL-5、IL-3、GM-CSF受体各自α链表达,抑制这3种受体的共同β链表达,减少其生物 学功能,促进Eos凋亡。
Objective To investigate expression of interle ukin-5 receptor α(IL-5Rα),interleukin-3 receptor α(IL-3Rα), granulocyte-macrophage-colony-stimulating factor receptor α(GM-CSFRα) and common β receptor(βcR) in eosinophils(Eos) of bronchoalveolar lavage fluid(B ALF) in asthmatic guinea pig and the effect of Triptolide(TP) on its expression, and to explore the mechanism of TP in promoting Eos apoptosis. Methods 18 guinea pigs were divided into three groups randomly, normal control group, asthma group and TP-treated group. Asthma model of guinea pigs were sensitized by ovalbumin(OVA). Hypodense Eos(HEos) and normodense Eos(NEos) were pur ified from BALF by gradients of percoll. Apoptosis was detected by TdT-mediated dUTP nick end labeling. Expression of all receptor mRNA were measured by hybrid ization and mRNA of IL-5Rα and IL-3Rα were measured by RT-PCR. Results Apoptosis of HEos and NEos in asthma group were lower than that of normal group, while the number of Eos cells were higher than that of normal group. Eos of BALF in asthmatic guinea pig were remarkably reduced after receiving TP, Eos apoptosis in TP-treated group BALF was significantly higher than that found in asthmatic group. Expression of IL-5Rα,IL-3Rα,GM-CSFRα mRNA in BALF Eos from asthmatic group were notably lower, expression of βcR mRNA was higher than that from normal group. Expression of all α receptors mRNA were significantly higher , while expression of βcR mRNA was lower in BALF Eos from TP-treated group than that from asthmatic group.Conclusions Apoptosis of Eos is inhibited in asthma. TP promotes the apoptosis in BALF Eos of guinea pigs with asthma. TP decreases the effect of IL-5, IL-3, GM-CSF and promotes apoptosis in lung Eos by inducing expression of their α chain mRNA and reducing expression of common β chain mRNA.
出处
《免疫学杂志》
CAS
CSCD
北大核心
2002年第2期102-106,共5页
Immunological Journal
基金
国家自然科学基金资助项目(39670337)