{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T03:02:58Z","timestamp":1792810978819,"version":"4.5.0"},"reference-count":43,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,6,28]],"date-time":"2021-06-28T00:00:00Z","timestamp":1624838400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>African swine fever (ASF) is an emerging disease threat to the swine industry worldwide. There is no vaccine against ASF, and progress is hindered by a lack of knowledge concerning the extent of ASFV strain diversity and the viral antigens conferring type-specific protective immunity in pigs. We have previously demonstrated that homologous ASFV serotype-specific proteins CD2v (EP402R) and\/or C-type lectin are required for protection against challenge with the virulent ASFV strain Congo (Genotype I, Serogroup 2), and we have identified T-cell epitopes on CD2v which may be associated with serotype-specific protection. Here, using a cell-culture adapted derivative of the ASFV strain Congo (Congo-a) with specific deletion of the EP402R gene (\u0394CongoCD2v) in swine vaccination\/challenge experiments, we demonstrated that deletion of the EP402R gene results in the failure of \u0394CongoCD2v to induce protection against challenge with the virulent strain Congo (Congo-v). While \u0394CongoCD2v growth kinetics in COS-1 cells and primary swine macrophage culture were almost identical to parental Congo-a, replication of \u0394CongoCD2v in vivo was significantly reduced compared with parental Congo-a. Our data support the idea that the CD2v protein is important for the ability of homologous live-attenuated vaccines to induce protective immunity against the ASFV strain Congo challenge in vivo.<\/jats:p>","DOI":"10.3390\/v13071259","type":"journal-article","created":{"date-parts":[[2021,6,28]],"date-time":"2021-06-28T13:39:22Z","timestamp":1624887562000},"page":"1259","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Growth Kinetics and Protective Efficacy of Attenuated ASFV Strain Congo with Deletion of the EP402 Gene"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6479-7800","authenticated-orcid":false,"given":"Galina","family":"Koltsova","sequence":"first","affiliation":[{"name":"Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3294-6602","authenticated-orcid":false,"given":"Andrey","family":"Koltsov","sequence":"additional","affiliation":[{"name":"Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5627-7696","authenticated-orcid":false,"given":"Sergey","family":"Krutko","sequence":"additional","affiliation":[{"name":"Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natalia","family":"Kholod","sequence":"additional","affiliation":[{"name":"Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2682-5145","authenticated-orcid":false,"given":"Edan R.","family":"Tulman","sequence":"additional","affiliation":[{"name":"Center of Excellence for Vaccine Research, Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, CT 06269, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4935-0891","authenticated-orcid":false,"given":"Denis","family":"Kolbasov","sequence":"additional","affiliation":[{"name":"Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1016\/S0368-1742(21)80031-4","article-title":"On A Form of Swine Fever Occurring in British East Africa (Kenya Colony)","volume":"34","year":"1921","journal-title":"J. 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