Wang Yuya, Dan Kena, Xue Xiaoling, Yang Xiongbo, Feng Xujiao, Yang Qingqing, Yang Jing, Chen Bangtao
Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China.
Department of Dermatology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China.
Gut Pathog. 2021 Nov 22;13(1):69. doi: 10.1186/s13099-021-00465-x.
The increase of inflammation-inducing enterobacteria was recently observed in severe hand, foot, and mouth disease (HFMD) caused by Enterovirus A71 (EV-A71). This study aimed to verify the occurrence of bacterial translocation (BT) and further explore the contributory role of BT to severity of EV-A71-mediated HFMD cases.
Serum specimens from 65 mild and 65 severe EV-A71-associated HFMD cases and 65 healthy children were collected. EV-A71 VP1 in serum, inflammatory mediators including C-reactive protein, IL-1β, IL-6, interferon-γ and tumor necrosis factor-α, BT related biomarkers including Claudin-3, intestinal fatty acid binding protein, lipopolysaccharide (LPS), soluble CD14 (sCD14) and endotoxin core antibody were measured by ELISA. Bacterial DNA (BactDNA) fragments were quantified by quantified PCR (qPCR). Rhabdomyosarcoma (RD) or SH-SY5Y cells, infected with LPS-pre-incubated EV-A71 or transfected with plasmid containing viral 2A or mRNA containing viral internal ribosomal entry site (IRES), were post-treated with or without LPS in vitro. EV-A71 RNA and viral or cellular proteins were determined by qPCR and western blot, respectively.
Compared to mild HFMD patients, remarkably higher inflammatory mediators as well as BT-related biomarkers except BactDNA were observed in severe HFMD cases (all P < 0.05). In severe HFMD group, circulating concentrations of LPS and sCD14 showed statistical correlations with inflammation indices (all P < 0.05), serum levels of EV-A71 VP1 were found to be positively correlated with serum LPS (r = 0.341, P = 0.005) and serum sCD14 (r = 0.458, P < 0.001). In vitro, EV-A71 attachment and internalization were only slightly promoted by LPS pre-incubation; however, EV-A71 proliferation and viral 2A-mediated IRES activity were significantly accelerated by LPS post-treatment.
Our results collectively indicate that gut-derived translocating LPS contributes to the severity of EV-A71-induced HFMD by driving inflammatory response and viral proliferation via viral 2A-mediated IRES.
最近在肠道病毒A71（EV - A71）引起的重症手足口病（HFMD）中观察到促炎肠杆菌增加。本研究旨在验证细菌易位（BT）的发生情况，并进一步探讨BT在EV - A71介导的HFMD病例严重程度中的作用。
收集65例轻度和65例重度EV - A71相关HFMD病例以及65例健康儿童的血清标本。采用酶联免疫吸附测定法（ELISA）检测血清中的EV - A71 VP1、包括C反应蛋白、白细胞介素 - 1β、白细胞介素 - 6、干扰素 - γ和肿瘤坏死因子 - α在内的炎症介质，以及包括紧密连接蛋白 - 3、肠脂肪酸结合蛋白、脂多糖（LPS）、可溶性CD14（sCD14）和内毒素核心抗体在内的BT相关生物标志物。通过定量聚合酶链反应（qPCR）对细菌DNA（BactDNA）片段进行定量。横纹肌肉瘤（RD）或SH - SY5Y细胞，用预先孵育LPS的EV - A71感染或用含有病毒2A的质粒转染或用含有病毒内部核糖体进入位点（IRES）的mRNA转染，在体外进行有或无LPS的后处理。分别通过qPCR和蛋白质印迹法测定EV - A71 RNA以及病毒或细胞蛋白。
与轻度HFMD患者相比，重度HFMD病例中观察到炎症介质以及除BactDNA外的BT相关生物标志物显著更高（所有P < 0.05）。在重度HFMD组中，循环中的LPS和sCD14浓度与炎症指标具有统计学相关性（所有P < 0.05），发现血清EV - A71 VP1水平与血清LPS呈正相关（r = 0.341，P = 0.005）以及与血清sCD14呈正相关（r = 0.458，P < 0.001）。在体外，预先孵育LPS仅轻微促进EV - A71的附着和内化；然而，LPS后处理显著加速了EV - A71的增殖以及病毒2A介导的IRES活性。
我们的结果共同表明，肠道来源的易位LPS通过病毒2A介导的IRES驱动炎症反应和病毒增殖，从而导致EV - A71诱导的HFMD病情加重。
