{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T10:17:50Z","timestamp":1783937870116,"version":"3.55.0"},"reference-count":47,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T00:00:00Z","timestamp":1783900800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"NIH","doi-asserted-by":"publisher","award":["5P30CA118100-21"],"award-info":[{"award-number":["5P30CA118100-21"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"NIH","doi-asserted-by":"publisher","award":["T32 AI007538"],"award-info":[{"award-number":["T32 AI007538"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Allocations Committee of the University of New Mexico School of Medicine"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Identifying antigens that elicit protective immunity is the key step for vaccine development. Here, we describe the use of the MS2 VLP platform to identify epitopes of SARS-CoV-2 structural proteins recognized by antibodies from COVID-19 patients, and to present those epitopes to the immune system as vaccines. We constructed an MS2 virus-like particle (VLP) library covering all four structural proteins of SARS-CoV-2 and affinity-selected vaccine candidates by biopanning on antibodies from infected humans. We focused on the structural proteins, reasoning that they are the most likely targets of a protective antibody response. The epitopes we found map almost entirely to the spike and nucleocapsid proteins. The VLPs displaying such epitopes were produced individually in E. coli and then tested for their potential as vaccines. While none of the affinity-selected spike-specific VLPs elicited neutralizing antibodies, VLPs displaying nucleocapsid epitopes induced protective immunity in a hamster model. This work illustrates the MS2 VLP platform\u2019s capacity for the identification of new vaccine candidates and raises the possibility that VLPs displaying nucleocapsid epitopes could provide long-lasting protection against a range of virus variants.<\/jats:p>","DOI":"10.3390\/v18070766","type":"journal-article","created":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T09:51:09Z","timestamp":1783936269000},"page":"766","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Affinity Selection of MS2 VLPs as SARS-CoV-2 Vaccine Candidates Targeting Nucleocapsid Protein"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8746-7513","authenticated-orcid":false,"given":"Julianne","family":"Peabody","sequence":"first","affiliation":[{"name":"Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunyan","family":"Ye","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1985-751X","authenticated-orcid":false,"given":"Steven","family":"Bradfute","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5712-4739","authenticated-orcid":false,"given":"Bryce","family":"Chackerian","sequence":"additional","affiliation":[{"name":"Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-7829-9851","authenticated-orcid":false,"given":"David S.","family":"Peabody","sequence":"additional","affiliation":[{"name":"Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1006\/abbi.1997.0312","article-title":"Subunit fusion confers tolerance to peptide insertions in a virus coat protein","volume":"347","author":"Peabody","year":"1997","journal-title":"Arch. 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