title: Middle East respiratory syndrome coronavirus infection mediated by the transmembrane serine protease TMPRSS2.
abstract: 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.
authors.affiliation: Department of Virology III, National Institute of Infectious Diseases, Murayama Branch, Musashi-Murayama, Tokyo, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Shirato
authors.forename: Miyuki
authors.initials: M
authors.lastname: Kawase
authors.forename: Shutoku
authors.initials: S
authors.lastname: Matsuyama
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology* / Q000821:virology; D017934:Coronavirus / Q000187:drug effects / Q000502:physiology*; D018352:Coronavirus Infections / Q000188:drug therapy / Q000201:enzymology* / Q000821:virology; D004952:Esters; D016670:Gabexate / Q000008:administration & dosage / Q000031:analogs & derivatives; D015726:Giant Cells / Q000187:drug effects / Q000821:virology; D006146:Guanidines; D006801:Humans; D012697:Serine Endopeptidases / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors / Q000008:administration & dosage; D053586:Virus Internalization / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D004952:Esters; D006146:Guanidines; D015842:Serine Proteinase Inhibitors; C034532:camostat; D016670:Gabexate; D012697:Serine Endopeptidases; C421305:TMPRSS2 protein, human
references.citation: PLoS One. 2010 Jan 15;5(1):e8729
references.pmid: 20090954
references.citation: J Virol. 2010 Jun;84(11):5605-14
references.pmid: 20237084
references.citation: J Virol. 2012 Jun;86(12):6537-45
references.pmid: 22496216
references.citation: Virology. 1997 Jan 6;227(1):153-9
references.pmid: 9007068
references.citation: Proc Natl Acad Sci U S A. 2004 Mar 23;101(12):4240-5
references.pmid: 15010527
references.citation: J Virol. 2009 Jan;83(2):712-21
references.pmid: 18971274
references.citation: Vaccine. 2009 Oct 23;27(45):6324-9
references.pmid: 19840668
references.citation: Euro Surveill. 2012 Sep 27;17(39):
references.pmid: 23041021
references.citation: Proc Natl Acad Sci U S A. 2005 Aug 30;102(35):12543-7
references.pmid: 16116101
references.citation: Trends Mol Med. 2009 Jul;15(7):303-12
references.pmid: 19581128
references.citation: J Virol. 2011 Dec;85(24):13363-72
references.pmid: 21994442
references.citation: J Infect Dis. 2013 Jun 1;207(11):1743-52
references.pmid: 23532101
references.citation: J Virol. 2013 Jul;87(14):7790-2
references.pmid: 23678167
references.citation: N Engl J Med. 2012 Nov 8;367(19):1814-20
references.pmid: 23075143
references.citation: J Virol. 2006 Oct;80(19):9896-8
references.pmid: 16973594
references.citation: J Virol. 2010 Oct;84(19):10016-25
references.pmid: 20631123
references.citation: J Virol. 2009 Apr;83(7):3200-11
references.pmid: 19158246
references.citation: Nature. 2013 Mar 14;495(7440):251-4
references.pmid: 23486063
references.citation: J Virol. 2008 Sep;82(17):8942-6
references.pmid: 18562527
references.citation: J Virol. 2010 Dec;84(24):12658-64
references.pmid: 20926566
references.citation: Rev Med Virol. 2010 Sep;20(5):298-310
references.pmid: 20629046
references.citation: mBio. 2012 Dec 11;3(6):
references.pmid: 23232719
references.citation: PLoS One. 2012;7(4):e35876
references.pmid: 22558251
references.citation: J Virol. 2011 Jan;85(2):873-82
references.pmid: 21068237
references.citation: J Virol. 2013 May;87(10):5502-11
references.pmid: 23468491
references.citation: J Virol. 2009 Nov;83(21):11133-41
references.pmid: 19706706
references.citation: J Virol. 2011 Aug;85(15):7872-80
references.pmid: 21613395