{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,10]],"date-time":"2026-11-10T16:53:44Z","timestamp":1794329624518,"version":"4.9.0"},"reference-count":85,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,11,23]],"date-time":"2024-11-23T00:00:00Z","timestamp":1732320000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Immunosenescence, a systematic reduction in the immune system connected with age, profoundly affects the health and well-being of elderly individuals. This review outlines the hallmark features of immunosenescence, including thymic involution, inflammaging, cellular metabolic adaptations, and hematopoietic changes, and their impact on immune cells such as macrophages, neutrophils, T cells, dendritic cells, B cells, and natural killer (NK) cells. Thymic involution impairs the immune system\u2019s capacity to react to novel antigens by reducing thymopoiesis and shifting toward memory T cells. Inflammaging, characterized by chronic systemic inflammation, further impairs immune function. Cellular metabolic adaptations and hematopoietic changes alter immune cell function, contributing to a diminished immune response. Developing ways to reduce immunosenescence and enhance immunological function in the elderly population requires an understanding of these mechanisms.<\/jats:p>","DOI":"10.3390\/vaccines12121314","type":"journal-article","created":{"date-parts":[[2024,11,25]],"date-time":"2024-11-25T03:59:01Z","timestamp":1732507141000},"page":"1314","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":173,"title":["Immunosenescence: Aging and Immune System Decline"],"prefix":"10.3390","volume":"12","author":[{"given":"Priyanka","family":"Goyani","sequence":"first","affiliation":[{"name":"Department of Biological Sciences, Kean University, Union, NJ 07083, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rafail","family":"Christodoulou","sequence":"additional","affiliation":[{"name":"Department of Radiology, School of Medicine, University of Patras, 265 04 Rio, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Evros","family":"Vassiliou","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, Kean University, Union, NJ 07083, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"391","DOI":"10.1054\/tice.1999.0001","article-title":"Proliferation, apoptosis and thymic involution","volume":"31","author":"Afek","year":"1999","journal-title":"Tissue Cell"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.molimm.2018.04.010","article-title":"Time-course transcriptome analysis of medullary thymic epithelial cells in the early phase of thymic involution","volume":"99","author":"Wu","year":"2018","journal-title":"Mol. 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