白细胞介素-5趋化嗜酸性粒细胞浸润呼吸道

INFILTRATION OF EOSINOPHILS INTO THE ASTHMATIC AIRWAYS INDUCED BY INTERLEUKIN 5

目的：为研究白细胞介素－５（ＩＬ－５）是否对嗜酸性粒细胞（ＥＯＳ）浸润支气管哮喘患者气道具有直接的趋化和激活作用。方法：将人重组ＩＬ－５经纤维支气管镜直接注入哮喘患者（８例）右中叶或左舌叶的肺段支气管，而将生理盐水注入对侧肺段支气管作为对照。２４ｈ后复经纤支镜于相应的肺段支气管收集支气管肺泡灌洗液（ＢＡＬＦ）及支气管粘膜组织。然后计数ＢＡＬＦ中的ＥＯＳ数并测定其中嗜酸阳离子蛋白（ＥＣＰ）水平，以免疫组织学技术显示粘膜组织中总ＥＯＳ（ＢＭＫ－１３＋）细胞及活化ＥＯＳ（ＥＧ２＋细胞）的浸润情况。结果：ＩＬ－５组ＢＡＬＦ中ＥＯＳ和ＥＣＰ水平显著高于对照组。而且，ＩＬ－５组ＢＭＫ１３＋和ＥＧ２＋细胞数也明显高于对照组。结论：ＩＬ－５不但可以趋化ＥＯＳ浸润到哮喘患者的气道，还可促使其活化。提示ＩＬ－５在哮喘气道的炎症过程中发挥极其重要的作用。

Objective:To investigate whether interleukin 5(IL 5) has direct chemoataxis for eosinophils infiltration into asthmatic airways,and as an activator for the infiltration eosinophils Method:eight subjects with mild atopic asthma underwent instillation into subsegment of the lingula or right middle lobe,and normal saline was instilled into asubsegment of the opposite lung 24h later,brochoalaveolar lavage fluid(BALF) and bronchial mucosal biopsies from each treated sites were obtained The number of epsinophils in BALF was counted,and concentrations of eosinophil cationic protein(ECP) in BALF were detected And eosinophils in beonchial mucosa were shown immunohistochemically by using two monoclonal antibodies(BMK 13 + and EG2) Result:It was found that there was an increase in eosinophil numbers in IL 5 challenged lavage when compared with control lavage;ECP levels in IL 5 challenged lavage were significantly higher than those in control lavage;both eosinophils(BMK 13 + cells) and the activated eosinophils(EG2 + cell) in mucosa exposed to IL 5 were much more than those in the control mucosa Conclusion:It could be conclued that IL 5 were capable of inducing infiltration of eosinophils into the asthmatic airways as well as activation of infiltrated eosinophils