{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T03:29:48Z","timestamp":1791343788806,"version":"4.3.1"},"reference-count":110,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T00:00:00Z","timestamp":1774569600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>The complement system is a key component of innate immunity, known primarily as an immune surveillance mechanism. However, it is also widely known as a modulator of immune responses and inflammation, and its activation has been reported in a wide array of conditions that can lead to admission to the intensive care unit (ICU). Furthermore, various ICU monitoring practices and treatment interventions of the ICU needed to sustain vital organ function may disrupt complement homeostasis. In this review, we will describe in detail the role of the complement system in various critical care settings, with emphasis on major ICU-related conditions such as bacterial and viral sepsis, trauma and burn. Additionally, we will address the potential value of this complex cascade as a prognosis tool and the possible implications for clinical practice as well as its potential as a target for future innovative therapeutic strategies.<\/jats:p>","DOI":"10.3390\/biom16040505","type":"journal-article","created":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T12:45:53Z","timestamp":1774615553000},"page":"505","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The Complement System in the Setting of Critical Illness\u2014A Narrative Review"],"prefix":"10.3390","volume":"16","author":[{"given":"Kleio","family":"Ampelakiotou","sequence":"first","affiliation":[{"name":"Department of Immunology and Histocompatibility, Evangelismos General Hospital, 10676 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioanna","family":"Nikitopoulou","sequence":"additional","affiliation":[{"name":"GP Livanos and M Simou Laboratories, 1st Department of Critical Care Medicine & Pulmonary Services, Evangelismos Hospital, School of Medicine, National and Kapodistrian University of Athens, 10675 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1082-8488","authenticated-orcid":false,"given":"Stelios","family":"Kokkoris","sequence":"additional","affiliation":[{"name":"GP Livanos and M Simou Laboratories, 1st Department of Critical Care Medicine & Pulmonary Services, Evangelismos Hospital, School of Medicine, National and Kapodistrian University of Athens, 10675 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2508-500X","authenticated-orcid":false,"given":"Anastasia","family":"Kotanidou","sequence":"additional","affiliation":[{"name":"GP Livanos and M Simou Laboratories, 1st Department of Critical Care Medicine & Pulmonary Services, Evangelismos Hospital, School of Medicine, National and Kapodistrian University of Athens, 10675 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2219-7292","authenticated-orcid":false,"given":"Ioanna","family":"Dimopoulou","sequence":"additional","affiliation":[{"name":"GP Livanos and M Simou Laboratories, 1st Department of Critical Care Medicine & Pulmonary Services, Evangelismos Hospital, School of Medicine, National and Kapodistrian University of Athens, 10675 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria G.","family":"Detsika","sequence":"additional","affiliation":[{"name":"GP Livanos and M Simou Laboratories, 1st Department of Critical Care Medicine & Pulmonary Services, Evangelismos Hospital, School of Medicine, National and Kapodistrian University of Athens, 10675 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1038\/nri.2017.36","article-title":"The immunopathology of sepsis and potential therapeutic targets","volume":"17","author":"Scicluna","year":"2017","journal-title":"Nat. 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