Recruitment of CD55 and CD66e brush border-associated glycosylphosphatidylinositol-anchored proteins by members of the Afa/Dr diffusely adhering family of Escherichia coli that infect the human polarized intestinal Caco-2/TC7 cells
Recruitment of CD55 and CD66e brush border-associated glycosylphosphatidylinositol-anchored proteins by members of the Afa/Dr diffusely adhering family of Escherichia coli that infect the human polarized intestinal Caco-2/TC7 cells
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DOI：
10.1128/iai.68.6.3554-3563.2000
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发表时间：
2000-06-01
影响因子：
3.1
通讯作者：
Servin, AL
中科院分区：
文献类型：
--
作者：
Guignot, J;Peiffer, I;Servin, AL
广泛粘附的大肠杆菌 (Afa/Dr DAEC) 的 Afa/Dr 家族包括表达菌毛粘附素 (AFA)、Dr 血凝素和菌毛 F1845 粘附素的细菌。我们表明，Afa/Dr DAEC 菌株 C1845 和 1H11128 感染人肠道 Caco-2/TC7 细胞后会聚集粘附细菌周围的 CD55。 Afa/Dr DAEC nas 使用 CHO 细胞中稳定转染表达的 CD55 缺失突变体对参与 CD55 聚类的 CD55 表位进行作图。短共有重复序列 1 (SCR1) 结构域的删除消除了 Afa/Dr DAEC 诱导的 CD55 聚类。相反，SCR4 结构域的缺失不会改变 Afa/Dr DAEC 诱导的 CD55 聚类。我们发现刷状缘相关的糖基磷脂酰肌醇 (GPI) 锚定蛋白 CD66e（癌胚抗原）被 Afa/Dr DAEC 菌株 C1845 和 1H11128 招募。这一结论基于以下观察结果：(i) Afa/Dr DAEC 菌株感染 Caco-2/TC7 细胞后，CD66e 聚集在粘附细菌周围；(ii) Afa/Dr DAEC 菌株有效结合到表达 CD66e 的稳定转染 HeLa 细胞，同时 CD66e 聚集在粘附细菌周围。使用针对 CD55 SCR 结构域的单克隆抗体以及多克隆抗 CD55 和抗 CD66e 抗体进行的抑制测定表明，CD55 和 CD66e 作为 C1845 和 1H11128 细菌的受体发挥作用。此外，使用结构draE基因突变体，我发现54位半胱氨酸取代天冬氨酸的突变体表现出保守的结合能力，但未能诱导CD55和CD66e聚类。总而言之，这些数据为 Afa/Dr DAEC 通过动员已知作为转导分子的刷状缘相关 GPI 锚定蛋白在人极化肠上皮细胞中诱导粘附素依赖性串扰的机制提供了新的见解。
The Afa/Dr family of diffusely adhering Escherichia coli (Afa/Dr DAEC) includes bacteria expressing afimbrial adhesins (AFA), Dr hemagglutinin, and fimbrial F1845 adhesin, We show that infection of human intestinal Caco-2/TC7 cells by the Afa/Dr DAEC strains C1845 and 1H11128 is followed by clustering of CD55 around adhering bacteria. Mapping of CD55 epitopes involved in CD55 clustering by Afa/Dr DAEC nas conducted using CD55 deletion mutants expressed by stable transfection in CHO cells. Deletion in the short consensus repeat 1 (SCR1) domain abolished Afa/Dr DAEC-induced CD55 clustering. In contrast, deletion in the SCR4 domain does not modify Afa/Dr DAEC-induced CD55 clustering. We show that the brush border-associated glycosylphosphatidylinositol (GPI)-anchored protein CD66e (carcinoembryonic antigen) is recruited by the Afa/Dr DAEC strains C1845 and 1H11128. This conclusion is based on the observations that (i) infection of Caco-2/TC7 cells by Afa/Dr DAEC strains is followed by clustering of CD66e around adhering bacteria and (ii) Afa/Dr DAEC strains bound efficiently to stably transfected HeLa cells expressing CD66e, accompanied by CD66e clustering around adhering bacteria. Inhibition assay using monoclonal antibodies directed against CD55 SCR domains, and polyclonal anti-CD55 and anti-CD66e antibodies demonstrate that CD55 and CD66e function as a receptors for the C1845 and 1H11128 bacteria. Moreover, using structural draE gene mutants, me found that a mutant in which cysteine replaced aspartic acid at position 54 displayed conserved binding capacity but failed to induce CD55 and CD66e clustering. Taken together, these data give new insights into the mechanisms by which Afa/Dr DAEC induces adhesin-dependent cross talk in the human polarized intestinal epithelial cells by mobilizing brush border-associated GPI-anchored proteins known to function as transducing molecules.