n Crohn's disease (CD), gut dysbiosis is marked by the prevalence of pathogenic bacterial species. Although several microbes have been reported as risk factors or causative agents of CD, it is not yet clear which is the real trigger of the disease. Thirty years ago, a new pathovar of Escherichia coli strain was isolated in the ileal mucosa of CD patients. This strain, called adherent invasive E. coli (AIEC), for its ability to invade the intestinal mucosa, could represent the causative agent of the disease. Several authors studied the mechanisms by which the AIEC penetrate and replicate within macrophages, and release inflammatory cytokines sustaining inflammation. In this review we will discuss about the role of AIEC in the pathogenesis of CD, the virulence factors mediating adhesion and invasion of AIEC in mucosal tissue, the environmental conditions improving AIEC survival and replication within macrophages. Finally, we will also give an overview of the new strategies developed to limit AIEC overgrowth.

中文翻译：

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克罗恩病的病原体：粘附性侵袭性大肠杆菌的作用

在克罗恩病 (CD) 中，肠道菌群失调的特点是致病菌种类的普遍存在。尽管据报道有几种微生物是克罗恩病的危险因素或致病因子，但目前尚不清楚哪种微生物是该疾病的真正触发因素。三十年前，在克罗恩病患者的回肠粘膜中分离出一种新的致病性大肠杆菌菌株。这种菌株被称为粘附性侵袭性大肠杆菌（AIEC），因其能够侵入肠粘膜，可能是该疾病的病原体。几位作者研究了 AIEC 穿透巨噬细胞并在巨噬细胞内复制并释放维持炎症的炎症细胞因子的机制。在这篇综述中，我们将讨论 AIEC 在 CD 发病机制中的作用、介导 AIEC 在粘膜组织中粘附和侵袭的毒力因子、改善 AIEC 在巨噬细胞内存活和复制的环境条件。最后，我们还将概述为限制 AIEC 过度增长而制定的新策略。