title: Crystal Structures of Yeast-Produced Enterovirus 71 and Enterovirus 71/Coxsackievirus A16 Chimeric Virus-Like Particles Provide the Structural Basis for Novel Vaccine Design against Hand-Foot-and-Mouth Disease.
abstract: Human enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) are the two major causative agents for hand-foot-and-mouth disease (HFMD). Previously, we demonstrated that a virus-like particle (VLP) for EV71 produced from Saccharomyces cerevisiae is a potential vaccine candidate against EV71 infection, and an EV71/CVA16 chimeric VLP can elicit protective immune responses against both virus infections. Here, we presented the crystal structures of both VLPs, showing that both the linear and conformational neutralization epitopes identified in EV71 are mostly preserved on both VLPs. The replacement of only 4 residues in the VP1 GH loop converted strongly negatively charged surface patches formed by portions of the SP70 epitope in EV71 VLP into a relatively neutral surface in the chimeric VLP, which likely accounted for the additional neutralization capability of the chimeric VLP against CVA16 infection. Such local variations in the amino acid sequences and the surface charge potential are also present in different types of polioviruses. In comparison to EV71 VLP, the chimeric VLP exhibits structural changes at the local site of amino acid replacement and the surface loops of all capsid proteins. This is consistent with the observation that the VP1 GH loop located near the pseudo-3-fold junction is involved in extensive interactions with other capsid regions. Furthermore, portions of VP0 and VP1 in EV71 VLP are at least transiently exposed, revealing the structural flexibility of the VLP. Together, our structural analysis provided insights into the structural basis of enterovirus neutralization and novel vaccine design against HFMD and other enterovirus-associated diseases.
  
  
  OBJECTIVE
  Our previous studies demonstrated that the enterovirus 71 (EV71) virus-like particle (VLP) produced from yeast is a vaccine candidate against EV71 infection and that a chimeric EV71/coxsackievirus A16 (CVA16) VLP with the replacement of 4 amino acids in the VP1 GH loop can confer protection against both EV71 and CVA16 infections. This study reported the crystal structures of both the EV71 VLP and the chimeric EV71/CVA16 VLP and revealed that the major neutralization epitopes of EV71 are mostly preserved in both VLPs. In addition, the mutated VP1 GH loop in the chimeric VLP is well exposed on the particle surface and exhibits a surface charge potential different from that contributed by the original VP1 GH loop in EV71 VLP. Together, this study provided insights into the structural basis of enterovirus neutralization and evidence that the yeast-produced VLPs can be developed into novel vaccines against hand-foot-and-mouth disease (HFMD) and other enterovirus-associated diseases.
authors.affiliation: Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Lyu
authors.affiliation: Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Ya-Ling
authors.initials: YL
authors.lastname: He
authors.affiliation: Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Hao-Yang
authors.initials: HY
authors.lastname: Li
authors.affiliation: Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China rongchen@ips.ac.cn.
authors.forename: Rong
authors.initials: R
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D004770:Enterovirus / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D029821:Enterovirus A, Human / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D006232:Hand, Foot and Mouth Disease / Q000517:prevention & control*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D014614:Vaccines, Synthetic / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification; D058425:Vaccines, Virus-Like Particle / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D014765:Viral Vaccines / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D000939:Epitopes; D014614:Vaccines, Synthetic; D058425:Vaccines, Virus-Like Particle; D014765:Viral Vaccines
references.citation: Proc Natl Acad Sci U S A. 1988 May;85(9):3203-7
references.pmid: 2834736
references.citation: J Biol Chem. 2015 Feb 6;290(6):3198-208
references.pmid: 25492868
references.citation: Nature. 1989 Jun 1;339(6223):385-8, 340
references.pmid: 2542797
references.citation: J Virol. 1990 Mar;64(3):1201-6
references.pmid: 2154604
references.citation: EMBO J. 1991 Sep;10(9):2331-41
references.pmid: 1651227
references.citation: J Gen Virol. 1991 Oct;72 ( Pt 10):2475-81
references.pmid: 1717641
references.citation: J Virol. 1994 Jun;68(6):3965-70
references.pmid: 7514682
references.citation: Methods Enzymol. 1997;276:594-611
references.pmid: 9048382
references.citation: Fold Des. 1996;1(3):179-87
references.pmid: 9079380
references.citation: Proc Natl Acad Sci U S A. 1998 Jun 9;95(12):6774-8
references.pmid: 9618488
references.citation: J Virol. 2005 Jun;79(12):7745-55
references.pmid: 15919927
references.citation: Virus Res. 2007 Apr;125(1):61-8
references.pmid: 17222936
references.citation: Clin Microbiol Infect. 2008 Mar;14(3):286-8
references.pmid: 18076666
references.citation: Acta Crystallogr D Biol Crystallogr. 2010 Feb;66(Pt 2):213-21
references.pmid: 20124702
references.citation: Acta Crystallogr D Biol Crystallogr. 2010 Apr;66(Pt 4):486-501
references.pmid: 20383002
references.citation: Vaccine. 2011 Jun 10;29(26):4362-72
references.pmid: 21501643
references.citation: Nat Struct Mol Biol. 2012 Apr;19(4):424-9
references.pmid: 22388738
references.citation: Curr Opin Virol. 2012 Apr;2(2):199-205
references.pmid: 22482716
references.citation: Science. 2012 Jun 8;336(6086):1274
references.pmid: 22383808
references.citation: Vaccine. 2012 Nov 19;30(49):7105-10
references.pmid: 23022400
references.citation: PLoS Pathog. 2013 Mar;9(3):e1003255
references.pmid: 23544011
references.citation: Vaccine. 2013 Apr 19;31(17):2130-6
references.pmid: 23499595
references.citation: Vaccine. 2013 Jul 11;31(32):3281-7
references.pmid: 23726823
references.citation: J Virol. 2013 Nov;87(21):11363-70
references.pmid: 23946455
references.citation: J Virol. 2014 Feb;88(3):1758-70
references.pmid: 24257617
references.citation: J Virol. 2014 Mar;88(6):3114-26
references.pmid: 24352461
references.citation: J Virol. 2014 Jun;88(11):6444-52
references.pmid: 24672036
references.citation: PLoS Negl Trop Dis. 2014;8(5):e2895
references.pmid: 24875055
references.citation: Nucleic Acids Res. 2014 Jul;42(Web Server issue):W320-4
references.pmid: 24753421
references.citation: Sci Rep. 2015;5:7878
references.pmid: 25597595
references.citation: Nature. 1988 Mar 3;332(6159):81-2
references.pmid: 2450279
references.citation: J Comput Chem. 2004 Oct;25(13):1605-12
references.pmid: 15264254
references.citation: EMBO J. 1988 Sep;7(9):2839-47
references.pmid: 2460345