Department of Pediatrics, Binhaiwan Central Hospital of Dongguan, Dongguan, China.
Department of Pediatrics, Binhaiwan Central Hospital of Dongguan, No. 111 Humen Avenue, Humen Town, Dongguan City, 523900, Guangdong Province, China.
Biotechnol Lett. 2021 Jul;43(7):1357-1369. doi: 10.1007/s10529-021-03115-z. Epub 2021 Apr 1.
Enterovirus71 (EV71), the major cause of hand, foot, and-mouth disease (HFMD), has increasingly become a public health challenge. Type I interferons (IFNs) can regulate innate and adaptive immune responses to pathogens. MicroRNAs (miRNAs) play regulatory roles in host innate immune responses to viral infections. However, the roles of miR-103 and miR-107 in EV71 infection remain unclear.
Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to determine the expression of miR-103, miR-107, suppressor of cytokine signaling 3 (SOCS3), VP1, IFN-α, and IFN-β. Virus titers were measured by 50% tissue culture infectious dose (TCID) assay. Western blot assay was conducted to detect the protein levels of VP1, IFN-α, IFN-β, SOCS3, signal transducer and activator of transcription 3 (STAT3), and phospho-STAT3 (p-STAT3). Immunofluorescence assay was used to detect the protein level of VP1. The concentrations of IFN-α and IFN-β were examined by Enzyme-linked immunosorbent assay (ELISA). The interaction between SOCS3 and miR-103/miR-107 was predicted by starBase and verified by dual-luciferase reporter assay and RNA pull-down assay.
MiR-103 and miR-107 were downregulated and SOCS3 was upregulated in serum from patients with EV71 and EV71-infected cells. Overexpression of miR-103 and miR-107 repressed EV71 replication by inhibiting EV71 titers and VP1 expression. Moreover, upregulation of miR-103 and miR-107 enhanced EV71-triggered the production of type I IFNs. In addition, miR-103 and miR-107 directly targeted SOCS3, and SOCS3 upregulation reversed the effects of miR-103 and miR-107 on EV71 replication and type I IFN response. Importantly, miR-103 and miR-107 increased STAT3 phosphorylation by targeting SOCS3 after EV71 infection.
MiR-103 and miR-107 suppressed EV71 replication and increased the production of type I IFNs by regulating SOCS3/STAT3 pathway, which might provide a novel strategy for developing effective antiviral therapy.
肠道病毒 71 型（EV71）是手足口病（HFMD）的主要病原体，已成为公共卫生领域的一大挑战。I 型干扰素（IFNs）可以调节固有免疫和适应性免疫对病原体的反应。微小 RNA（miRNAs）在宿主对病毒感染的固有免疫反应中发挥调节作用。然而，miR-103 和 miR-107 在 EV71 感染中的作用尚不清楚。
采用实时定量聚合酶链反应（qRT-PCR）检测 miR-103、miR-107、细胞因子信号转导抑制因子 3（SOCS3）、VP1、IFN-α 和 IFN-β 的表达。采用 50%组织培养感染剂量（TCID）测定法测定病毒滴度。采用 Western blot 检测 VP1、IFN-α、IFN-β、SOCS3、信号转导和转录激活因子 3（STAT3）和磷酸化 STAT3（p-STAT3）的蛋白水平。采用免疫荧光法检测 VP1 蛋白水平。采用酶联免疫吸附试验（ELISA）检测 IFN-α 和 IFN-β 的浓度。采用 starBase 预测 SOCS3 与 miR-103/miR-107 的相互作用，并通过双荧光素酶报告基因检测和 RNA 下拉实验进行验证。
EV71 患者血清和 EV71 感染细胞中 miR-103 和 miR-107 下调，SOCS3 上调。miR-103 和 miR-107 的过表达通过抑制 EV71 滴度和 VP1 表达抑制 EV71 复制。此外，miR-103 和 miR-107 的上调增强了 EV71 触发的 I 型 IFN 的产生。此外，miR-103 和 miR-107 直接靶向 SOCS3，SOCS3 的上调逆转了 miR-103 和 miR-107 对 EV71 复制和 I 型 IFN 反应的影响。重要的是，miR-103 和 miR-107 通过靶向 SOCS3 增加了 EV71 感染后 STAT3 的磷酸化。
miR-103 和 miR-107 通过调节 SOCS3/STAT3 通路抑制 EV71 复制并增加 I 型 IFN 的产生，这可能为开发有效的抗病毒治疗提供新策略。
