Middle East Respiratory Syndrome Coronavirus Infection Mediated by the Transmembrane Serine Protease TMPRSS2
Middle East Respiratory Syndrome Coronavirus Infection Mediated by the Transmembrane Serine Protease TMPRSS2
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DOI：
10.1128/jvi.01890-13
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发表时间：
2013-12-01
影响因子：
5.4
通讯作者：
Matsuyama, Shutoku
中科院分区：
文献类型：
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作者：
Shirato, Kazuya;Kawase, Miyuki;Matsuyama, Shutoku
中东呼吸综合征冠状病毒（MERS-CoV）利用宿主蛋白酶进入肺细胞。在本研究中，组成性表达II型跨膜丝氨酸蛋白酶的Vero细胞（Vero- tmprss2细胞）在感染MERS-CoV后18 h的合胞体比感染其他冠状病毒后的合胞体大。此外，Vero- tmprss2细胞对MERS-CoV的易感性比不表达tmprss2的亲本Vero细胞高100倍。抑制TMPRSS2活性的丝氨酸蛋白酶抑制剂camostat完全阻断合胞体的形成，但仅部分阻断病毒进入Vero-TMPRSS2细胞。重要的是，冠状病毒被认为通过两种不同的途径进入细胞，一种是由细胞表面的TMPRSS2介导的，另一种是由内体中的组织蛋白酶L介导的。组织蛋白酶L和TMPRSS2抑制剂同时处理，完全阻断病毒进入Vero-TMPRSS2细胞，表明MERS-CoV同时通过细胞表面和内体途径感染Vero-TMPRSS2细胞。相比之下，单独使用卡莫他可抑制MERS-CoV进入人支气管粘膜下腺来源的Calu-3细胞10倍，抑制病毒生长270倍，尽管同时使用卡莫他和(23,25)-反式环氧琥珀酰-l -乙酰氨基-3-甲基丁烷乙酯（一种组织蛋白酶抑制剂）或用白细胞蛋白酶（一种半胱氨酸、丝氨酸和苏氨酸肽酶抑制剂）治疗并不比单独使用卡莫他更有效。此外，这些抑制剂对来自肺的MRC-5和WI-38细胞的MERS-CoV感染无效，但这些特性与成熟肺细胞不同。这些结果表明，单次使用卡莫司他就足以阻止MERS-CoV进入分化良好的肺源细胞系。
The Middle East respiratory syndrome coronavirus (MERS-CoV) utilizes host proteases for virus entry into lung cells. In the current study, Vero cells constitutively expressing type II transmembrane serine protease (Vero-TMPRSS2 cells) showed larger syncytia at 18 h after infection with MERS-CoV than after infection with other coronaviruses. Furthermore, the susceptibility of Vero-TMPRSS2 cells to MERS-CoV was 100-fold higher than that of non-TMPRSS2-expressing parental Vero cells. The serine protease inhibitor camostat, which inhibits TMPRSS2 activity, completely blocked syncytium formation but only partially blocked virus entry into Vero-TMPRSS2 cells. Importantly, the coronavirus is thought to enter cells via two distinct pathways, one mediated by TMPRSS2 at the cell surface and the other mediated by cathepsin L in the endosome. Simultaneous treatment with inhibitors of cathepsin L and TMPRSS2 completely blocked virus entry into Vero-TMPRSS2 cells, indicating that MERS-CoV employs both the cell surface and the endosomal pathway to infect Vero-TMPRSS2 cells. In contrast, a single camostat treatment suppressed MERS-CoV entry into human bronchial submucosal gland-derived Calu-3 cells by 10-fold and virus growth by 270-fold, although treatment with both camostat and (23,25)-trans-epoxysuccinyl-L-leucylamindo-3-methylbutane ethyl ester, a cathepsin inhibitor, or treatment with leupeptin, an inhibitor of cysteine, serine, and threonine peptidases, was no more efficacious than treatment with camostat alone. Further, these inhibitors were not efficacious against MERS-CoV infection of MRC-5 and WI-38 cells, which were derived from lung, but these characters differed from those of mature pneumocytes. These results suggest that a single treatment with camostat is sufficient to block MERS-CoV entry into a well-differentiated lung-derived cell line.