{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T06:21:04Z","timestamp":1783923664869,"version":"3.55.0"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,9]],"date-time":"2023-02-09T00:00:00Z","timestamp":1675900800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002261","name":"Russian Foundation for Basic Research","doi-asserted-by":"publisher","award":["20-54-12007"],"award-info":[{"award-number":["20-54-12007"]}],"id":[{"id":"10.13039\/501100002261","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Inactivated vaccines are promising tools for tackling the COVID-19 pandemic. We applied several protocols for SARS-CoV-2 inactivation (by \u03b2-propiolactone, formaldehyde, and UV radiation) and examined the morphology of viral spikes, protein composition of the preparations, and their immunoreactivity in ELISA using two panels of sera collected from convalescents and people vaccinated by Sputnik V. Transmission electron microscopy (TEM) allowed us to distinguish wider flail-like spikes (supposedly the S-protein\u2019s pre-fusion conformation) from narrower needle-like ones (the post-fusion state). While the flails were present in all preparations studied, the needles were highly abundant in the \u03b2-propiolactone-inactivated samples only. Structural proteins S, N, and M of SARS-CoV-2 were detected via mass spectrometry. Formaldehyde and UV-inactivated samples demonstrated the highest affinity\/immunoreactivity against the convalescent sera, while \u03b2-propiolactone (1:2000, 36 h) and UV-inactivated ones were more active against the sera of people vaccinated with Sputnik V. A higher concentration of \u03b2-propiolactone (1:1000, 2 h) led to a loss of antigenic affinity for both serum panels. Thus, although we did not analyze native SARS-CoV-2 for biosafety reasons, our comparative approach helped to exclude some destructive inactivation conditions and select suitable variants for future animal research. We believe that TEM is a valuable tool for inactivated COVID-19 vaccine quality control during the downstream manufacturing process.<\/jats:p>","DOI":"10.3390\/v15020480","type":"journal-article","created":{"date-parts":[[2023,2,9]],"date-time":"2023-02-09T02:32:07Z","timestamp":1675909927000},"page":"480","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Structural and Immunoreactivity Properties of the SARS-CoV-2 Spike Protein upon the Development of an Inactivated Vaccine"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6089-1103","authenticated-orcid":false,"given":"Larisa V.","family":"Kordyukova","sequence":"first","affiliation":[{"name":"Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrey V.","family":"Moiseenko","sequence":"additional","affiliation":[{"name":"Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina V.","family":"Serebryakova","sequence":"additional","affiliation":[{"name":"Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7550-5519","authenticated-orcid":false,"given":"Marina A.","family":"Shuklina","sequence":"additional","affiliation":[{"name":"WHO National Influenza Center, Smorodintsev Research Institute of Influenza, 197376 Saint-Petersburg, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0411-9896","authenticated-orcid":false,"given":"Maria V.","family":"Sergeeva","sequence":"additional","affiliation":[{"name":"WHO National Influenza Center, Smorodintsev Research Institute of Influenza, 197376 Saint-Petersburg, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dmitry A.","family":"Lioznov","sequence":"additional","affiliation":[{"name":"WHO National Influenza Center, Smorodintsev Research Institute of Influenza, 197376 Saint-Petersburg, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9801-9911","authenticated-orcid":false,"given":"Andrei V.","family":"Shanko","sequence":"additional","affiliation":[{"name":"R&D Department, FORT LLC, 119435 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"735","DOI":"10.1016\/0264-410X(95)00211-I","article-title":"Inactivated poliovirus vaccine: Past and present experience","volume":"14","author":"Murdin","year":"1996","journal-title":"Vaccine"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"746","DOI":"10.1016\/S1473-3099(21)00020-7","article-title":"Inactivated COVID-19 vaccines to make a global impact","volume":"21","author":"Iversen","year":"2021","journal-title":"Lancet Infect. 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