Adherent-invasive Escherichia coli (AIEC) (AIEC)

Adherent-invasive Escherichia coli (AIEC) is a pathotype of E. coli that is significantly associated with the ileal mucosa of patients with Crohn's disease (Darfeuille-Michaud et al., 2004; PubMed: 15307858). These bacteria are defined by their ability to adhere to and invade intestinal epithelial cells and to survive and replicate within macrophages, leading to the secretion of high levels of tumor necrosis factor-alpha (TNF-α) (Glasser et al., 2001; PubMed: 11553593). The interaction is largely mediated by bacterial FimH adhesins binding to overexpressed host CEACAM6 receptors in the inflamed gut (Barnich et al., 2007; PubMed: 17324403). AIEC persistence within the intestinal niche is thought to drive the chronic transmural inflammation and granuloma formation characteristic of Crohn's disease. Therapeutic interventions targeting AIEC include small-molecule FimH antagonists, such as Sibofimloc (EB8018/TAK-018), which aim to block bacterial attachment and promote clearance (Enterome, 2019). Additionally, bacteriophage therapy and specific probiotics are being explored to selectively eliminate or outcompete AIEC strains without disrupting the broader commensal microbiota (Galtier et al., 2017; PubMed: 28348172).

Other names

AIECCrohn's disease-associated Escherichia coliPathogenic ileal E. coliCD-associated E. coli

FimH antagonism to prevent mucosal adhesion; bactericidal activity via antibiotics or bacteriophages; competitive exclusion by probiotics.