{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T17:50:02Z","timestamp":1789753802698,"version":"4.0.1"},"reference-count":31,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,10,20]],"date-time":"2020-10-20T00:00:00Z","timestamp":1603152000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000180","name":"U.S. Department of Homeland Security","doi-asserted-by":"publisher","award":["70RSAT18KPM000056"],"award-info":[{"award-number":["70RSAT18KPM000056"]}],"id":[{"id":"10.13039\/100000180","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>African swine fever virus (ASFV) is currently the most dreaded infectious disease affecting the global swine production industry. There is no commercial vaccine available, making the culling of infected animals the current solution to control outbreaks. Effective experimental vaccines have been developed by deleting virus genes associated with virulence. Deletion of the ASFV 9GL gene (\u22069GL) has resulted in the attenuation of different ASFV strains, although the degree of attenuation varies across isolates. Here, we investigated the possibility of the increased safety of the experimental vaccine strain ASFV-G-\u03949GL by deleting two additional virus genes involved in pathogenesis, CD2v, a CD2 like viral encoded gene from the EP402R open reading frame (ORF), and C-type lectin-like viral gene, encoded from the EP153R ORF. Two new recombinant viruses were developed, ASFV-G-\u03949GL\/\u0394CD2v and ASFV-G-\u03949GL\/\u0394CD2v\/\u0394EP153R, harboring two and three gene deletions, respectively. ASFV-G-\u03949GL\/\u0394CD2v\/\u0394EP153R, but not ASFV-G-\u03949GL\/\u0394CD2v, had a decreased ability to replicate in vitro in swine macrophage cultures when compared with parental ASFV-G-\u03949GL. Importantly, ASFV-G-\u03949GL\/\u0394CD2v and ASFV-G-\u03949GL\/\u0394CD2v\/\u0394EP153R induced almost undetectable viremia levels when inoculated into domestic pigs and failed to protect them against challenge with parental virulent ASFV-Georgia, while ASFV-G-\u03949GL offered robust protection during challenge. Therefore, the deletion of CD2-like and C-type lectin-like genes significantly decreased the protective potential of ASFV-G-\u03949GL as a vaccine candidate. This study constitutes an example of the unpredictability of genetic manipulation involving the simultaneous deletion of multiple genes from the ASFV genome.<\/jats:p>","DOI":"10.3390\/v12101185","type":"journal-article","created":{"date-parts":[[2020,10,20]],"date-time":"2020-10-20T09:28:23Z","timestamp":1603186103000},"page":"1185","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":75,"title":["Deletion of CD2-Like (CD2v) and C-Type Lectin-Like (EP153R) Genes from African Swine Fever Virus Georgia-\u22069GL Abrogates Its Effectiveness as an Experimental Vaccine"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7894-0233","authenticated-orcid":false,"given":"Douglas P.","family":"Gladue","sequence":"first","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vivian","family":"O\u2019Donnell","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Plum Island Animal Disease Center, APHIS, USDA, Greenport, NY 11944, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth","family":"Ramirez-Medina","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Department of Anatomy and Physiology, Kansas State University, Manhattan, KS 66506, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayushi","family":"Rai","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Pruitt","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth A.","family":"Vuono","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Department of Pathobiology and Population Medicine, Mississippi State University, Mississippi State, MS 39762, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ediane","family":"Silva","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Department of Anatomy and Physiology, Kansas State University, Manhattan, KS 66506, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauro","family":"Velazquez-Salinas","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"},{"name":"Department of Anatomy and Physiology, Kansas State University, Manhattan, KS 66506, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manuel V.","family":"Borca","sequence":"additional","affiliation":[{"name":"Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.vetmic.2016.10.003","article-title":"Challenges for African Swine Fever Vaccine Development\u2014Perhaps the End of the Beginning","volume":"206","author":"Rock","year":"2017","journal-title":"Veter. 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