Fusco Alessandra, Savio Vittoria, Donniacuo Maria, Perfetto Brunella, Donnarumma Giovanna
Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy.
Front Cell Infect Microbiol. 2021 Jun 10;11:666900. doi: 10.3389/fcimb.2021.666900. eCollection 2021.
The intestinal mucosa is composed of a monolayer of epithelial cells, which is highly polarized and firmly united to each other thanks to the presence of proteins complexes, called Tight junctions (TJs). Alteration of the mucus layer and TJs causes an increase in intestinal permeability, which can lead to a microbial translocation and systemic disorders. , in addition to its role of commensal, is an opportunistic pathogen responsible for disseminated candidiasis, especially in immunocompromised subjects where the dysbiosis leads to damage of the intestinal mucosal barrier . In this work, we used a line of intestinal epithelial cells able to stably express the genes that encodes human beta defensin-2 (HBD-2) and -3 (HBD-3) to monitor the invasion of Defensins are a group of antimicrobial peptides (AMPs) found in different living organisms, and are involved in the first line of defense in the innate immune response against pathogens. The results obtained show that the presence of antimicrobial peptides improves the expression of TJs and increases the Trans Epithelial Electrical Resistence value. In addition, the invasive ability of in transfected cells is significantly reduced, as well as the expression levels of genes involved in the apoptotic pathway. Through the study of interaction between antimicrobial peptides and microbiota we will be able in the future to better understand the mechanisms by which they exert the host defense function against intestinal pathogens.
肠道黏膜由单层上皮细胞组成,这些细胞高度极化,并由于存在称为紧密连接(TJs)的蛋白质复合物而彼此紧密相连。黏液层和紧密连接的改变会导致肠道通透性增加,进而可能导致微生物易位和全身紊乱。 ,除了作为共生菌的作用外,还是一种机会性病原体,可导致播散性念珠菌病,尤其是在免疫功能低下的受试者中,其中生态失调会导致肠道黏膜屏障受损。在这项工作中,我们使用了一种能够稳定表达编码人β-防御素-2(HBD-2)和-3(HBD-3)基因的肠道上皮细胞系,以监测 的侵袭。防御素是在不同生物体中发现的一组抗菌肽(AMPs),并参与针对病原体的先天免疫反应的第一道防线。获得的结果表明,抗菌肽的存在改善了紧密连接的表达并增加了跨上皮电阻值。此外,转染细胞中的 侵袭能力以及凋亡途径中相关基因的表达水平均显著降低。通过研究抗菌肽与微生物群之间的相互作用,我们将来将能够更好地理解它们发挥针对肠道病原体的宿主防御功能的机制。