{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T11:54:33Z","timestamp":1791806073216,"version":"4.3.4"},"reference-count":40,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,15]],"date-time":"2021-11-15T00:00:00Z","timestamp":1636934400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hospital General de M\u00e9xico","award":["DI\/20\/601\/04\/29"],"award-info":[{"award-number":["DI\/20\/601\/04\/29"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>The production of specific neutralizing antibodies by individuals is thought to be the best option for reducing the number of patients with severe COVID-19, which is the reason why multiple vaccines are currently being administered worldwide. We aimed to explore the effect of revaccination with BCG, on the response to a subsequent anti-SARS-CoV-2 vaccine, in persons occupationally exposed to COVID-19 patients. Two groups of 30 randomized participants were selected: one group received a BCG revaccination, and the other group received a placebo. Subsequently, both groups were vaccinated against SARS-CoV-2. After each round of vaccination, the serum concentration of Th1\/Th2 cytokines was determined. At the end of the protocol, neutralizing antibodies were determined and the HLA-DRB loci were genotyped. The participants from the BCG group and anti-SARS-CoV-2 vaccine group had increased serum cytokine concentrations (i.e., IL-1\u03b2, IL-4, IL-6, IL-12p70, IL-13, IL-18, GM-CSF, INF-\u03b3, and TNF-\u03b1) and higher neutralizing antibody titers, compared to the group with Placebo\u2013anti-SARS-CoV-2. Twelve HLA-DRB1 alleles were identified in the Placebo\u2013anti-SARS-CoV-2 group, and only nine in the group revaccinated with BCG. The DRB1*04 allele exhibited increased frequency in the Placebo\u2013anti-SARS-CoV-2 group; however, no confounding effects were found with this allele. We conclude that revaccination with BCG synergizes with subsequent vaccination against SARS-CoV-2 in occupationally exposed personnel.<\/jats:p>","DOI":"10.3390\/cells10113179","type":"journal-article","created":{"date-parts":[[2021,11,15]],"date-time":"2021-11-15T20:46:47Z","timestamp":1637009207000},"page":"3179","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Effect of BCG Revaccination on Occupationally Exposed Medical Personnel Vaccinated against SARS-CoV-2"],"prefix":"10.3390","volume":"10","author":[{"given":"Espiridi\u00f3n","family":"Ramos-Martinez","sequence":"first","affiliation":[{"name":"Unidad de Investigaci\u00f3n en Medicina Experimental, Facultad de Medicina, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Ciudad de M\u00e9xico 06720, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6877-8124","authenticated-orcid":false,"given":"Ramc\u00e9s","family":"Falf\u00e1n-Valencia","sequence":"additional","affiliation":[{"name":"HLA Laboratory, Instituto Nacional de Enfermedades Respiratorias Ismael Cos\u00edo Villegas, Mexico City 14080, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6876-1012","authenticated-orcid":false,"given":"Gloria","family":"P\u00e9rez-Rubio","sequence":"additional","affiliation":[{"name":"HLA Laboratory, Instituto Nacional de Enfermedades Respiratorias Ismael Cos\u00edo Villegas, Mexico City 14080, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2709-6463","authenticated-orcid":false,"given":"Warrison Athanasio","family":"Andrade","sequence":"additional","affiliation":[{"name":"Departamento de Biologia Celular e Molecular e Bioagentes Patog\u00eanicos, Faculdade de Medicina de Ribeir\u00e3o Preto, Universidade de S\u00e3o Paulo, Ribeir\u00e3o Preto 14049-900, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jorge","family":"Rojas-Serrano","sequence":"additional","affiliation":[{"name":"Unidad de enfermedades del Intersticio Pulmonar y Reumatolog\u00eda, Instituto Nacional de Enfermedades Respiratorias, \u201cIsmael Cos\u00edo Villegas\u201d, Ciudad de M\u00e9xico 14080, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1240-0637","authenticated-orcid":false,"given":"Enrique","family":"Ambrocio-Ortiz","sequence":"additional","affiliation":[{"name":"HLA Laboratory, Instituto Nacional de Enfermedades Respiratorias Ismael Cos\u00edo Villegas, Mexico City 14080, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dennisse S.","family":"Galicia-\u00c1lvarez","sequence":"additional","affiliation":[{"name":"Servicio de Alergia e Inmunolog\u00eda Cl\u00ednica, Hospital General de M\u00e9xico, \u201cDr. Eduardo Liceaga\u201d, Mexico City 06720, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isaac","family":"B\u00e1rcenas-Montiel","sequence":"additional","affiliation":[{"name":"Servicio de Alergia e Inmunolog\u00eda Cl\u00ednica, Hospital General de M\u00e9xico, \u201cDr. Eduardo Liceaga\u201d, Mexico City 06720, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Velasco-Medina","sequence":"additional","affiliation":[{"name":"Servicio de Alergia e Inmunolog\u00eda Cl\u00ednica, Hospital General de M\u00e9xico, \u201cDr. Eduardo Liceaga\u201d, Mexico City 06720, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guillermo","family":"Vel\u00e1zquez-S\u00e1mano","sequence":"additional","affiliation":[{"name":"Servicio de Alergia e Inmunolog\u00eda Cl\u00ednica, Hospital General de M\u00e9xico, \u201cDr. Eduardo Liceaga\u201d, Mexico City 06720, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"343","DOI":"10.3389\/fcimb.2018.00343","article-title":"Back to the Future: Lessons Learned From the 1918 Influenza Pandemic","volume":"8","author":"Short","year":"2018","journal-title":"Front. 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