{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T04:16:49Z","timestamp":1787631409604,"version":"build-2736575974"},"reference-count":122,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,3,29]],"date-time":"2021-03-29T00:00:00Z","timestamp":1616976000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>Following respiratory viral infections or local immunizations, lung resident-memory T cells (T<jats:sub>RM<\/jats:sub>) of the CD8 lineage provide protection against the same pathogen or related pathogens with cross-reactive T cell epitopes. Yet, it is now clear that, if homeostatic controls are lost following viral pneumonia, CD8 T<jats:sub>RM<\/jats:sub> cells can mediate pulmonary pathology. We recently showed that the aging process can result in loss of homeostatic controls on CD8 T<jats:sub>RM<\/jats:sub> cells in the respiratory tract. This may be germane to treatment modalities in both influenza and coronavirus disease 2019 (COVID-19) patients, particularly, the portion that present with symptoms linked to long-lasting lung dysfunction. Here, we review the developmental cues and functionalities of CD8 T<jats:sub>RM<\/jats:sub> cells in viral pneumonia models with a particular focus on their capacity to mediate heterogeneous responses of immunity and pathology depending on immune status.<\/jats:p>","DOI":"10.3389\/fimmu.2021.636118","type":"journal-article","created":{"date-parts":[[2021,3,29]],"date-time":"2021-03-29T05:37:31Z","timestamp":1616996251000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":22,"title":["Age-Related Dynamics of Lung-Resident Memory CD8+ T Cells in the Age of COVID-19"],"prefix":"10.3389","volume":"12","author":[{"given":"Nick P.","family":"Goplen","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"In Su","family":"Cheon","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Sun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,3,29]]},"reference":[{"key":"B1","unstructured":"CD8+ T cells clear influenza virus by perforin or Fas-dependent processes5197200\n            TophamDJ\n            TrippRA\n            DohertyPC\n          9548456J Immunol.1591997"},{"key":"B2","doi-asserted-by":"publisher","first-page":"448","DOI":"10.1128\/JVI.01812-10","article-title":"T cell-mediated protection against lethal 2009 pandemic H1N1 influenza virus infection in a mouse model","volume":"85","author":"Guo","year":"2011","journal-title":"J Virol."},{"key":"B3","doi-asserted-by":"publisher","first-page":"e46166","DOI":"10.1371\/journal.pone.0046166","article-title":"Multiple distinct forms of CD8+ T cell cross-reactivity and specificities revealed after 2009 H1N1 influenza A virus infection in mice","volume":"7","author":"Guo","year":"2012","journal-title":"PLoS ONE."},{"key":"B4","doi-asserted-by":"publisher","first-page":"203","DOI":"10.4049\/jimmunol.1402975","article-title":"Airway-resident memory CD8 T cells provide antigen-specific protection against respiratory virus challenge through rapid IFN-gamma production","volume":"195","author":"McMaster","year":"2015","journal-title":"J Immunol."},{"key":"B5","doi-asserted-by":"publisher","first-page":"eaaw1217","DOI":"10.1126\/sciimmunol.aaw1217","article-title":"PD-1(hi) CD8(+) resident memory T cells balance immunity and fibrotic sequelae","volume":"4","year":"2019","journal-title":"Sci Immunol."},{"key":"B6","doi-asserted-by":"publisher","first-page":"eabc4557","DOI":"10.1126\/sciimmunol.abc4557","article-title":"Tissue-resident CD8(+) T cells drive age-associated chronic lung sequelae after viral pneumonia","volume":"5","author":"Goplen","year":"2020","journal-title":"Sci Immunol"},{"key":"B7","doi-asserted-by":"publisher","first-page":"173","DOI":"10.1038\/s41590-017-0029-3","article-title":"Intravital mucosal imaging of CD8(+) resident memory T cells shows tissue-autonomous recall responses that amplify secondary memory","volume":"19","author":"Beura","year":"2018","journal-title":"Nat Immunol."},{"key":"B8","doi-asserted-by":"publisher","first-page":"98","DOI":"10.1126\/science.1254536","article-title":"T cell memory. 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