Institute of Medical Biology, Chinese Academy of Medical Science and Peking Union Medical College, Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Kunming, China.
Front Cell Infect Microbiol. 2018 Apr 9;8:110. doi: 10.3389/fcimb.2018.00110. eCollection 2018.
Enterovirus 71 (EV-A71) and coxsackievirus A16 (CV-A16) remain the predominant etiological agents of hand, foot, and mouth disease (HFMD). The clinical manifestations caused by the two viruses are obviously different. CV-A16 usually triggers a repeated infection, and airway epithelial integrity is often the potential causative factor of respiratory repeated infections. Our previous studies have demonstrated that there were some differentially expressed miRNAs involved in the regulation of adhesion function of epithelial barrier in EV-A71 and CV-A16 infections. In this study, we compared the differences between EV-A71 and CV-A16 infections on the airway epithelial barrier function in human bronchial epithelial (16HBE) cells and further screened the key miRNA which leaded to the formation of these differences. Our results showed that more rapid proliferation, more serious destruction of 16HBE cells permeability, more apoptosis and disruption of intercellular adhesion-associated molecules were found in CV-A16 infection as compared to EV-A71 infection. Furthermore, we also identified that microRNA-4516 (miR-4516), which presented down-regulation in EV-A71 infection and up-regulation in CV-A16 infection was an important regulator of intercellular junctions by targeting Poliovirus receptor related protein 1(PVRL1). The expressions of PVRL1, claudin4, ZO-1 and E-cadherin in CV-A16-infected cells were significantly less than those in EV-A71-infected cells, while the expressions of these proteins were subverted when pre-treated with miR-4516-overexpression plasmid in EV-A71 infected and miR-4516-knockdown plasmid in CV-A16 infected 16HBE cells. Thus, these data suggested that the opposite expression of miR-4516 in EV-A71 and CV-A16 infections might be the initial steps leading to different epithelial impairments of 16HBE cells by destroying intercellular adhesion, which finally resulted in different outcomes of EV-A71 and CV-A16 infections.
肠道病毒 71 型（EV-A71）和柯萨奇病毒 A16 型（CV-A16）仍是手足口病（HFMD）的主要病原体。这两种病毒引起的临床表现明显不同。CV-A16 通常会引发反复感染，而气道上皮完整性往往是呼吸道反复感染的潜在原因。我们之前的研究表明，EV-A71 和 CV-A16 感染中存在一些差异表达的 miRNA，参与调节上皮屏障的黏附功能。在本研究中，我们比较了 EV-A71 和 CV-A16 感染对人支气管上皮（16HBE）细胞气道上皮屏障功能的差异，并进一步筛选出导致这些差异形成的关键 miRNA。结果表明，CV-A16 感染比 EV-A71 感染导致 16HBE 细胞更快增殖、更严重破坏细胞通透性、更多细胞凋亡和破坏细胞间黏附相关分子。此外，我们还发现，miR-4516（miR-4516）在 EV-A71 感染中下调，在 CV-A16 感染中上调，是通过靶向 PVRL1 调节细胞间连接的重要调节剂。CV-A16 感染细胞中 PVRL1、claudin4、ZO-1 和 E-cadherin 的表达明显低于 EV-A71 感染细胞，而在 EV-A71 感染细胞中转染 miR-4516 过表达质粒和在 CV-A16 感染细胞中转染 miR-4516 敲低质粒后，这些蛋白的表达被逆转。因此，这些数据表明，EV-A71 和 CV-A16 感染中 miR-4516 的相反表达可能是通过破坏细胞间黏附导致 16HBE 细胞上皮损伤不同的初始步骤，最终导致 EV-A71 和 CV-A16 感染的不同结果。
