{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:12:43Z","timestamp":1792789963188,"version":"4.5.0"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,24]],"date-time":"2019-12-24T00:00:00Z","timestamp":1577145600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003336","name":"Bulgarian National Science Fund","doi-asserted-by":"publisher","award":["DNTC\/Russia 02-6"],"award-info":[{"award-number":["DNTC\/Russia 02-6"]}],"id":[{"id":"10.13039\/501100003336","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["739582"],"award-info":[{"award-number":["739582"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002261","name":"Russian Foundation for Basic Research","doi-asserted-by":"publisher","award":["18-54-18005"],"award-info":[{"award-number":["18-54-18005"]}],"id":[{"id":"10.13039\/501100002261","id-type":"DOI","asserted-by":"publisher"}]},{"name":"UK Biotechnological and Biological Sciences Research Council (BBSRC)","award":["BB\/J004596\/1"],"award-info":[{"award-number":["BB\/J004596\/1"]}]},{"name":"UK Biotechnological and Biological Sciences Research Council (BBSRC)","award":["BB\/P012523\/1"],"award-info":[{"award-number":["BB\/P012523\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>The Hepatitis E virus (HEV) is a causative agent of acute hepatitis, mainly transmitted by the fecal-oral route or zoonotic. Open reading frame (ORF) 2 encodes the viral capsid protein, which is essential for virion assembly, host interaction, and inducing neutralizing antibodies. In this study, we investigated whether full-length and N- and C-terminally modified versions of the capsid protein transiently expressed in N. benthamiana plants could assemble into highly-immunogenic, virus-like particles (VLPs). We also assessed whether such VLPs can act as a carrier of foreign immunogenic epitopes, such as the highly-conserved M2e peptide from the Influenza virus. Plant codon-optimized HEV ORF2 capsid genes were constructed in which the nucleotides coding the N-terminal, the C-terminal, or both parts of the protein were deleted. The M2e peptide was inserted into the P2 loop after the residue Gly556 of HEV ORF2 protein by gene fusion, and three different chimeric constructs were designed. Plants expressed all versions of the HEV capsid protein up to 10% of total soluble protein (TSP), including the chimeras, but only the capsid protein consisting of aa residues 110 to 610 (HEV 110\u2013610) and chimeric M2 HEV 110\u2013610 spontaneously assembled in higher order structures. The chimeric VLPs assembled into particles with 22\u201336 nm in diameter and specifically reacted with the anti-M2e antibody.<\/jats:p>","DOI":"10.3390\/plants9010029","type":"journal-article","created":{"date-parts":[[2019,12,24]],"date-time":"2019-12-24T10:28:43Z","timestamp":1577183323000},"page":"29","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Rapid High-Yield Transient Expression of Swine Hepatitis E ORF2 Capsid Proteins in Nicotiana benthamiana Plants and Production of Chimeric Hepatitis E Virus-Like Particles Bearing the M2e Influenza Epitope"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7667-9924","authenticated-orcid":false,"given":"Gergana G.","family":"Zahmanova","sequence":"first","affiliation":[{"name":"Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria"},{"name":"Center of Plant System Biology and Biotechnology, 4000 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milena","family":"Mazalovska","sequence":"additional","affiliation":[{"name":"Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katerina H.","family":"Takova","sequence":"additional","affiliation":[{"name":"Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valentina T.","family":"Toneva","sequence":"additional","affiliation":[{"name":"Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria"},{"name":"Institute of Molecular Biology and Biotechnologies, 4000 Plovdiv, Bulgari"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9331-353X","authenticated-orcid":false,"given":"Ivan N.","family":"Minkov","sequence":"additional","affiliation":[{"name":"Center of Plant System Biology and Biotechnology, 4000 Plovdiv, Bulgaria"},{"name":"Institute of Molecular Biology and Biotechnologies, 4000 Plovdiv, Bulgari"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2148-7658","authenticated-orcid":false,"given":"Eugenia S.","family":"Mardanova","sequence":"additional","affiliation":[{"name":"Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nikolai V.","family":"Ravin","sequence":"additional","affiliation":[{"name":"Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George P.","family":"Lomonossoff","sequence":"additional","affiliation":[{"name":"Department of Biological Chemistry, John Innes Centre, Norwich NR4 7UH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1046\/j.1365-2893.2003.00398.x","article-title":"Aetiology, clinical course and outcome of sporadic acute viral hepatitis in pregnancy","volume":"10","author":"Khuroo","year":"2003","journal-title":"J. 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