{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T15:38:49Z","timestamp":1787067529368,"version":"build-2736575974"},"reference-count":35,"publisher":"BMJ","issue":"4","license":[{"start":{"date-parts":[[2024,12,31]],"date-time":"2024-12-31T00:00:00Z","timestamp":1735603200000},"content-version":"unspecified","delay-in-days":30,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004336","name":"Novartis","doi-asserted-by":"publisher","award":["OptiRef study"],"award-info":[{"award-number":["OptiRef study"]}],"id":[{"id":"10.13039\/100004336","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["FKZ 01EC1903E and GESPIC-AS cohort"],"award-info":[{"award-number":["FKZ 01EC1903E and GESPIC-AS cohort"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100017268","name":"Berlin Institute of Health","doi-asserted-by":"crossref","award":["GESPIC-AS cohort"],"award-info":[{"award-number":["GESPIC-AS cohort"]}],"id":[{"id":"10.13039\/501100017268","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["RMD Open"],"accepted":{"date-parts":[[2024,11,25]]},"published-print":{"date-parts":[[2024,12]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>The objective of this study is to investigate lipopolysaccharid-binding protein (LBP), zonulin and calprotectin as markers of bacterial translocation, disturbed gut barrier and intestinal inflammation in patients with radiographic axial spondyloarthritis (r-axSpA) during tumour necrosis factor inhibitor (TNFi) therapy and to analyze the association between disease activity, response to treatment and biomarker levels.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Patients with active r-axSpA of the German Spondyloarthritis Inception Cohort starting TNFi were compared with controls with chronic back pain. Serum levels of LBP, zonulin and calprotectin were measured at baseline and after 1 year of TNFi therapy. We analysed the longitudinal association between biomarkers and disease activity, and the relationship between biomarkers and treatment response with regression analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>121 patients with r-axSpA were compared with 63 controls. At baseline, patients with r-axSpA had higher levels of LBP and calprotectin than controls, which decreased significantly during TNFi treatment. LBP showed a positive association in longitudinal analyses with Axial Spondyloarthritis Disease Activity Score (ASDAS) (\u00df=0.08, 95% CI 0.06 to 0.10), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (\u00df=0.08, 95% CI 0.04 to 0.12) and C reactive protein (CRP) (\u00df=1.69, 95% CI 1.04 to 2.34). Calprotectin was associated with ASDAS (\u00df=0.04, 95% CI 0.01 to 0.07) and CRP (\u00df=0.82, 95% CI 0.27 to 1.37). Furthermore, LBP and calprotectin levels at baseline showed an association with a subsequent change in BASDAI. Baseline zonulin levels were not significantly associated with disease activity or treatment response.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Serum levels of LBP and calprotectin are associated with disease activity in patients with r-axSpA and decrease with TNFi response. In contrast, serum zonulin levels showed no association with disease activity or treatment response, arguing against a strict correlation between intestinal permeability and disease activity in axSpA.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/rmdopen-2024-004752","type":"journal-article","created":{"date-parts":[[2024,12,31]],"date-time":"2024-12-31T11:35:19Z","timestamp":1735644919000},"page":"e004752","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":8,"title":["Biomarkers reflecting disturbed gut barrier under treatment with TNF inhibitors in radiographic axial spondyloarthritis"],"prefix":"10.1136","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7442-2570","authenticated-orcid":false,"given":"Judith","family":"Rademacher","sequence":"first","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"},{"name":"Berlin Institute of Health at Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4600-9484","authenticated-orcid":false,"given":"Murat","family":"Torgutalp","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine Maria","family":"Hempel","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4306-033X","authenticated-orcid":false,"given":"Fabian","family":"Proft","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hildrun","family":"Haibel","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4840-5069","authenticated-orcid":false,"given":"Mikhail","family":"Protopopov","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Spiller","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4537-6015","authenticated-orcid":false,"given":"Denis","family":"Poddubnyy","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5612-043X","authenticated-orcid":false,"given":"Valeria","family":"Rios Rodriguez","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectiology and Rheumatology (including Nutrition Medicine), Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, corporate member of Freie Universit\u00e4t Berlin and Humboldt-Universit\u00e4t zu Berlin, Berlin, 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Widely Used Commercial ELISA Does Not Detect Precursor of Haptoglobin2, but Recognizes Properdin as a Potential Second Member of the Zonulin Family. 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