{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T10:01:21Z","timestamp":1790676081703,"version":"4.1.0"},"reference-count":33,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,9,13]],"date-time":"2022-09-13T00:00:00Z","timestamp":1663027200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002858","name":"the China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2021M701594"],"award-info":[{"award-number":["2021M701594"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"the China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2021B1212030014"],"award-info":[{"award-number":["2021B1212030014"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guangdong Science and Technology Program Key Projects","award":["2021M701594"],"award-info":[{"award-number":["2021M701594"]}]},{"name":"Guangdong Science and Technology Program Key Projects","award":["2021B1212030014"],"award-info":[{"award-number":["2021B1212030014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>In the context of the COVID-19 pandemic, conducting antibody testing and vaccination is critical. In particular, the continued evolution of SARS-CoV-2 raises concerns about the effectiveness of vaccines currently in use and the activity of neutralizing antibodies. Here, we used the Escherichia coli expression system to obtain nine different SARS-CoV-2 RBD protein variants, including six single-point mutants, one double-point mutant, and two three-point mutants. Western blotting results show that nine mutants of the RBD protein had strong antigenic activity in vitro. The immunogenicity of all RBD proteins was detected in mice to screen for protein mutants with high immunogenicity. The results show that the mutants E484K, E484Q, K417T-E484K-N501Y, and K417N-E484K-N501Y, especially the former two, had better immunogenicity than the wild type. This suggests that site E484 has a significant impact on the function of the RBD protein. Our results demonstrate that recombinant RBD protein expressed in E. coli can be an effective tool for the development of antibody detection methods and vaccines.<\/jats:p>","DOI":"10.3390\/v14092020","type":"journal-article","created":{"date-parts":[[2022,9,14]],"date-time":"2022-09-14T00:15:02Z","timestamp":1663114502000},"page":"2020","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Enhancing the Immunogenicity of RBD Protein Variants through Amino Acid E484 Mutation in SARS-CoV-2"],"prefix":"10.3390","volume":"14","author":[{"given":"Zhikai","family":"Zhang","sequence":"first","affiliation":[{"name":"BSL-3 Laboratory (Guangdong), Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuan","family":"Wan","sequence":"additional","affiliation":[{"name":"Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyue","family":"Li","sequence":"additional","affiliation":[{"name":"BSL-3 Laboratory (Guangdong), Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaoxi","family":"Cai","sequence":"additional","affiliation":[{"name":"Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chengsong","family":"Wan","sequence":"additional","affiliation":[{"name":"BSL-3 Laboratory (Guangdong), Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"689","DOI":"10.1016\/S0140-6736(20)30260-9","article-title":"Nowcasting and forecasting the potential domestic and international spread of the 2019-nCoV outbreak originating in Wuhan, China: A modelling study","volume":"395","author":"Wu","year":"2020","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1470","DOI":"10.3201\/eid2607.200282","article-title":"High Contagiousness and Rapid Spread of Severe Acute Respiratory Syndrome Coronavirus 2","volume":"26","author":"Sanche","year":"2020","journal-title":"Emerg. 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