Moqbel R, Ying S, Barkans J, Newman T M, Kimmitt P, Wakelin M, Taborda-Barata L, Meng Q, Corrigan C J, Durham S R, Kay A B
Department of Allergy and Clinical Immunology, National Heart and Lung Institute, Royal Brompton Hospital, London, United Kingdom.
J Immunol. 1995 Nov 15;155(10):4939-47.
Human eosinophils are cytokine-producing cells that are prominent in IgE-dependent allergic tissue reactions. IL-4 promotes the development of the Th2-type phenotype in T cells and is an essential cofactor for IgE production by B cells. We detected mRNA for IL-4 by reverse transcription-PCR in blood eosinophils from atopic asthmatics. By specific ELISA, 108 +/- 20 pg of IL-4 protein/10(6) cells could be extracted from whole cells, and approximately 30% of the IL-4 was released after incubation with serum-coated particles. Using immunocytochemistry, eosinophils from atopic asthmatics and nonatopic controls showed IL-4 immunoreactivity using an anti-IL-4 mAb. IL-4 was located predominantly in the eosinophil granules, as shown by both immunogold electron microscopy and a cell fractionation technique that dissociated cell granules from membrane and cytosolic components. IL-4 mRNA colocalized with eosinophils (using sequential immunocytochemistry with an eosinophil-specific (EG2) mAb and in situ hybridization using an IL-4-specific antisense riboprobe) in both cell cytospins from bronchoalveolar lavage fluid from asthmatics as well as skin biopsies obtained from allergen-induced late phase (6-h) reactions in atopic subjects. Using double immunocytochemistry on skin biopsies with eosinophil- and IL-4-specific mAb, 83.5 +/- 3.5% of eosinophils were IL-4+. Conversely, eosinophils accounted for 46.5 +/- 3.9% of the total cells expressing IL-4 immunoreactivity. Thus, human eosinophils express mRNA for IL-4, and the translated product is contained within the crystalloid granule from which it is released after stimulation with serum-coated particles. These observations are consistent with the hypothesis that eosinophils contribute to the development of the Th2 phenotype by T cells infiltrating atopic allergic reactions as well as to IgE synthesis.
人类嗜酸性粒细胞是产生细胞因子的细胞，在IgE依赖的过敏性组织反应中很突出。白细胞介素-4（IL-4）促进T细胞中Th2型表型的发育，并且是B细胞产生IgE的必需辅助因子。我们通过逆转录聚合酶链反应（RT-PCR）在特应性哮喘患者的血液嗜酸性粒细胞中检测到IL-4的信使核糖核酸（mRNA）。通过特异性酶联免疫吸附测定（ELISA），可从全细胞中提取108±20皮克IL-4蛋白/10⁶个细胞，并且在用血清包被颗粒孵育后约30%的IL-4被释放。使用免疫细胞化学方法，特应性哮喘患者和非特应性对照的嗜酸性粒细胞在用抗IL-4单克隆抗体（mAb）检测时显示出IL-4免疫反应性。免疫金电子显微镜和一种将细胞颗粒与膜及胞质成分分离的细胞分级分离技术均表明，IL-4主要位于嗜酸性粒细胞颗粒中。在哮喘患者支气管肺泡灌洗液的细胞涂片以及特应性受试者变应原诱导的迟发期（6小时）反应的皮肤活检组织中，IL-4 mRNA与嗜酸性粒细胞共定位（使用嗜酸性粒细胞特异性（EG2）mAb进行连续免疫细胞化学以及使用IL-4特异性反义核糖探针进行原位杂交）。在皮肤活检组织上使用嗜酸性粒细胞和IL-4特异性mAb进行双重免疫细胞化学检测，83.5±3.5%的嗜酸性粒细胞呈IL-4阳性。相反，嗜酸性粒细胞占表达IL-4免疫反应性的总细胞的46.5±3.9%。因此，人类嗜酸性粒细胞表达IL-4的mRNA，并且翻译产物包含在晶体颗粒中，在用血清包被颗粒刺激后从该颗粒中释放。这些观察结果与以下假设一致，即嗜酸性粒细胞通过浸润特应性过敏反应的T细胞促进Th2表型的发展以及IgE的合成。
