{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T01:26:01Z","timestamp":1782523561308,"version":"3.54.5"},"reference-count":39,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T00:00:00Z","timestamp":1756425600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Innovative Medizinische Forschung (IMF), Medizinische Fakult\u00e4t, Westf\u00e4lische Wilhelms-Universit\u00e4t M\u00fcnster, Germany","award":["TE212102"],"award-info":[{"award-number":["TE212102"]}]},{"name":"Open Access Publication Fund of the University of Muenster","award":["TE212102"],"award-info":[{"award-number":["TE212102"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Interleukin-24 (IL-24) is a cytokine known for its role in immune regulation and apoptosis, with potential implications in viral infections like COVID-19. This study aimed to investigate the association between IL-24 serum levels and the severity of COVID-19 disease. In this prospective bi-center cross-sectional study, we enrolled 41 COVID-19 patients from two hospitals in Germany. Serial blood samples were collected from a subset of patients, resulting in 88 total blood samples. Patients were categorized into critical, severe, moderate, and mild disease groups based on WHO criteria. IL-24 serum levels were measured during the acute or convalescent phase using an ELISA assay. Inflammatory markers, and kidney and liver function parameters were also evaluated. Statistical analysis included non-parametric tests and correlation analysis. Elevated IL-24 serum levels were observed in ambulant patients (mild disease), compared to hospitalized patients (critical, severe, moderate disease, p &lt; 0.05). IL-24 levels were also significantly higher in patients without oxygenation disorder compared to those with oxygenation therapy (p &lt; 0.05). A negative correlation was found between IL-24 levels and markers of inflammation and liver\/kidney function. Elevated IL-24 serum levels were associated with milder COVID-19 courses, suggesting a protective role in modulating immune responses and promoting antiviral apoptosis. Conversely, reduced IL-24 in severe cases may reflect impaired immune regulation, highlighting its potential as a biomarker and therapeutic target.<\/jats:p>","DOI":"10.3390\/ijms26178403","type":"journal-article","created":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T16:42:21Z","timestamp":1756485741000},"page":"8403","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["IL-24 in COVID-19 Patients: Correlations with Disease Progression"],"prefix":"10.3390","volume":"26","author":[{"given":"Richard","family":"Vollenberg","sequence":"first","affiliation":[{"name":"Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katharina","family":"Sch\u00fctte-N\u00fctgen","sequence":"additional","affiliation":[{"name":"Department of Medicine D, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital of M\u00fcnster, 48149 Muenster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Markus","family":"Strauss","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Faculty of Health, School of Medicine, University of Witten\/Herdecke, 58455 Witten, Germany"},{"name":"Department of Cardiology I\u2014Coronary and Peripheral Vascular Disease, Heart Failure Medicine, University Hospital Muenster, 48149 Muenster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonel","family":"Trebicka","sequence":"additional","affiliation":[{"name":"Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Fischer","sequence":"additional","affiliation":[{"name":"Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2757-4755","authenticated-orcid":false,"given":"Phil-Robin","family":"Tepasse","sequence":"additional","affiliation":[{"name":"Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Vollenberg, R., Matern, P., Nowacki, T., Fuhrmann, V., Padberg, J.-S., Ochs, K., Sch\u00fctte-N\u00fctgen, K., Strau\u00df, M., Schmidt, H., and Tepasse, P.-R. 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