Abstract:Objective To investigate the effect of extracellular vesicles (EVs) on inflammatory bowel disease. (IBD) via detecting the influence of intestinal luminal EVs on intestinal epithelial cells and macrophages.? Methods Forty patients with IBD from January 2016 to December 2017 and 20 normal population without abnormalities in enteroscopy and without chronic diseases history (HC group) were selected as research objective. The 10 ml intestinal luminal aspirates (LAs) were collected during colonoscopy in all chosen subjects, and the EVs were isolated. EVs were co-cultured with colon epithelial cell line SW-480 cells or macrophages derived from peripheral blood monocytes in vitro. Real-time quantitative polymerase chain reaction (qRT-PCR) and enzyme linked immunosorbent assay (ELISA) were used to detect cytokines mRNAs expressions and contents of their proteins in lysis buffer of EVs and in epithelial cells and macrophages after swallow EVs Macrophage migration test was performed to explore the effect of EVs on functions of macrophages.? Results (1) Compared with healthy subjects (HC), the expression levels of interleukin (IL) -6, IL-8, IL-10, tumor necrosis factor-α (TNF-α) mRNAs and their proteins contents in lysis buffer of EVs of IBD patients LAs (IBD-EVs) increased significantly, and the expression levels of transforming growth factor-β (TGF-β) and mucoprotein-2 (MUC-2) mRNAs and their protein contents decreased significantly. (2) Compared with co-culture with HC-EVs, the expression levels of IL-6, IL-8, IL-10, TNF-α mRNAs and their proteins contents in epithelial cells co-cultured with IBD-EVs after swallow EVs increased significantly, and the expression levels of TGF-β and MUC-2 mRNAs and their protein contents decreased significantly. The changes of cytokine levels in macrophages co-cultured with IBD-EVs after swallow EVs were similar to epithelial cells co-cultured with IBD-EVs after swallow EVs, and IBD-EVs can significantly increase the migration rate of macrophage.? Conclusion The inclusions released by EVs in LAs of IBD patients are different from HC. The experiment in vitro shows that IBD-EVs have the functions of promoting inflammation of intestinal epithelial cells and macrophages, and their stability and the characteristics of mRNA and protein profiles contained in them may be used as the potential fecal markers for clinical diagnosis of IBD.