{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T17:01:05Z","timestamp":1779296465830,"version":"3.51.4"},"reference-count":68,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,6]],"date-time":"2023-02-06T00:00:00Z","timestamp":1675641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The Bacillus Calmette\u2013Gu\u00e9rin (BCG) vaccine has been in use for over 100 years. It protects against severe, blood-borne forms of tuberculosis. Observations indicate that it also increases immunity against other diseases. The mechanism responsible for this is trained immunity, an increased response of non-specific immune cells in repeated contact with a pathogen, not necessarily of the same species. In the following review, we present the current state of knowledge on the molecular mechanisms responsible for this process. We also seek to identify the challenges facing science in this area and consider the application of this phenomenon in managing the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic.<\/jats:p>","DOI":"10.3390\/ijms24043218","type":"journal-article","created":{"date-parts":[[2023,2,7]],"date-time":"2023-02-07T01:56:48Z","timestamp":1675735008000},"page":"3218","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Trained Immunity, BCG and SARS-CoV-2 General Outline and Possible Management in COVID-19"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9935-472X","authenticated-orcid":false,"given":"Pawe\u0142","family":"Zapolnik","sequence":"first","affiliation":[{"name":"College of Medical Sciences, University of Rzesz\u00f3w, 35-315 Rzesz\u00f3w, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wojciech","family":"Kmiecik","sequence":"additional","affiliation":[{"name":"St. Louis Provincial Specialist Children\u2019s Hospital, 31-503 Krak\u00f3w, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5393-3515","authenticated-orcid":false,"given":"Artur","family":"Mazur","sequence":"additional","affiliation":[{"name":"College of Medical Sciences, University of Rzesz\u00f3w, 35-315 Rzesz\u00f3w, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanna","family":"Czajka","sequence":"additional","affiliation":[{"name":"College of Medical Sciences, University of Rzesz\u00f3w, 35-315 Rzesz\u00f3w, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1038\/s41577-020-0337-y","article-title":"BCG-induced trained immunity: Can it offer protection against COVID-19?","volume":"20","author":"Netea","year":"2020","journal-title":"Nat. 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