{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T01:37:57Z","timestamp":1792546677916,"version":"4.5.0"},"reference-count":46,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T00:00:00Z","timestamp":1780272000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["R01CA263324"],"award-info":[{"award-number":["R01CA263324"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,6,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Memory T-cell inflation is a distinctive immunological phenomenon observed during persistent viral infections such as cytomegalovirus (CMV). Unlike conventional memory T-cell responses, which contract after infection resolution, a subset of CMV-specific T cells undergoes a progressive and sustained expansion, termed \u201cinflation\u201d, which is thought to be critical for long-term immune surveillance. The molecular mechanisms that govern memory T-cell inflation remain incompletely understood, yet they are pivotal for understanding immune persistence and designing strategies against chronic viral infections. In this study, we investigated the role of MAPK-activated protein kinase 2 (MK2), a key downstream effector of p38 MAPK signaling, in regulating T-cell responses during murine CMV (MCMV) infection. Using MK2 knockout (MK2-KO) mice, we demonstrate that MK2 deficiency alters the dynamics of MCMV-specific CD8+ T-cell responses without impairing viral control or tissue replication. MK2 deficiency led to a reduction in noninflationary MCMV-specific CD8+ T cells during acute infection, followed by enhanced expansion of inflationary CD8+ T-cell subsets during latent infection. Furthermore, MK2-KO mice exhibited impaired effector differentiation, as evidenced by decreased expression of the terminal differentiation marker KLRG1 on MCMV-specific CD8+ T cells. Collectively, these findings identify MK2 as an important regulator of CD8+ T-cell magnitude, kinetics, and phenotype during both acute and latent MCMV infection. By demonstrating a role of MK2 in the regulation of memory T-cell inflation, this study provides new mechanistic insight into immune regulation with implications for vaccination, chronic infection, and immune aging.<\/jats:p>","DOI":"10.1093\/jimmun\/vkag170","type":"journal-article","created":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T17:52:17Z","timestamp":1782496337000},"source":"Crossref","is-referenced-by-count":1,"title":["MAPK-activated protein kinase 2 orchestrates memory T-cell inflation in cytomegalovirus infection"],"prefix":"10.1093","volume":"215","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7574-1378","authenticated-orcid":false,"given":"Eleni","family":"Panagioti","sequence":"first","affiliation":[{"name":"Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School , Boston, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xueyang","family":"Yu","sequence":"additional","affiliation":[{"name":"Center for Precision Cancer Medicine, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology , Cambridge, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi Wen","family":"Kong","sequence":"additional","affiliation":[{"name":"Center for Precision Cancer Medicine, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology , Cambridge, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristina","family":"Macakova","sequence":"additional","affiliation":[{"name":"Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School , Boston, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Noe B","family":"Mercado","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Legorreta Cancer Center, Brown University , Providence, RI,","place":["United States"]},{"name":"The Warren Alpert Medical School, Brown University , Providence, RI,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sean Edward","family":"Lawler","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Legorreta Cancer Center, Brown University , Providence, RI,","place":["United States"]},{"name":"The Warren Alpert Medical School, Brown University , Providence, RI,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael B","family":"Yaffe","sequence":"additional","affiliation":[{"name":"Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School , Boston, MA,","place":["United States"]},{"name":"Center for Precision Cancer Medicine, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology , Cambridge, MA,","place":["United States"]},{"name":"Department of Biological Engineering, Massachusetts Institute of Technology , Cambridge, MA,","place":["United States"]},{"name":"Department of Biology, Massachusetts Institute of Technology , Cambridge, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles H","family":"Cook","sequence":"additional","affiliation":[{"name":"Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School , Boston, MA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,6,26]]},"reference":[{"key":"2026062613521139000_vkag170-B1","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1038\/s41392-023-01471-y","article-title":"T cells in health and 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