{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T02:46:11Z","timestamp":1778121971595,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,3,7]],"date-time":"2021-03-07T00:00:00Z","timestamp":1615075200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001826","name":"ZonMw","doi-asserted-by":"publisher","award":["10070012010004"],"award-info":[{"award-number":["10070012010004"]}],"id":[{"id":"10.13039\/501100001826","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Elevated Serum Amyloid A (SAA) levels have been found in several inflammatory diseases, including sarcoidosis. SAA is suggested to be involved in sarcoidosis pathogenesis by involvement in granuloma formation and maintenance. We hypothesized that SAA serum levels would be higher in sarcoidosis compared to other non-infectious granulomatous and non-granulomatous diseases. SAA levels were measured in serum from sarcoidosis, Hypersensitivity pneumonitis (HP), and (eosinophilic) granulomatosis with polyangiitis ((E)GPA) patients. Idiopathic pulmonary fibrosis (IPF) patients were included as non-granulomatous disease group. SAA levels of patients with sarcoidosis (31.0 \u00b5g\/mL), HP (23.4 \u00b5g\/mL), (E)GPA (36.9 \u00b5g\/mL), and IPF (22.1 \u00b5g\/mL) were all higher than SAA levels of healthy controls (10.1 \u00b5g\/mL). SAA levels did not differ between the diagnostic groups. When SAA serum levels were analyzed in sarcoidosis subgroups, fibrotic sarcoidosis patients showed higher SAA levels than sarcoidosis patients without fibrosis (47.8 \u00b5g\/mL vs. 29.4 \u00b5g\/mL, p = 0.005). To conclude, the observation that fibrotic sarcoidosis patients have higher SAA levels, together with our finding that SAA levels were also increased in IPF patients, suggests that SAA may next to granulomatous processes also reflect the process of fibrogenesis. Further studies should clarify the exact role of SAA in fibrosis and the underlying mechanisms involved.<\/jats:p>","DOI":"10.3390\/cells10030585","type":"journal-article","created":{"date-parts":[[2021,3,7]],"date-time":"2021-03-07T20:20:43Z","timestamp":1615148443000},"page":"585","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Elevated Serum Amyloid a Levels Are not Specific for Sarcoidosis but Associate with a Fibrotic Pulmonary Phenotype"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0439-2550","authenticated-orcid":false,"given":"Els","family":"Beijer","sequence":"first","affiliation":[{"name":"Interstitial Lung Diseases Centre of Excellence, Department of Pulmonology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudia","family":"Roodenburg-Benschop","sequence":"additional","affiliation":[{"name":"Interstitial Lung Diseases Centre of Excellence, Department of Pulmonology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"},{"name":"Department of Medical Microbiology and Immunology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Milou C.","family":"Schimmelpennink","sequence":"additional","affiliation":[{"name":"Interstitial Lung Diseases Centre of Excellence, Department of Pulmonology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan C.","family":"Grutters","sequence":"additional","affiliation":[{"name":"Interstitial Lung Diseases Centre of Excellence, Department of Pulmonology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"},{"name":"Division of Heart and Lungs, University Medical Centre, 3584 CX Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3410-9912","authenticated-orcid":false,"given":"Bob","family":"Meek","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology and Immunology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcel","family":"Veltkamp","sequence":"additional","affiliation":[{"name":"Interstitial Lung Diseases Centre of Excellence, Department of Pulmonology, St. Antonius Hospital, 3435 CM Nieuwegein, The Netherlands"},{"name":"Division of Heart and Lungs, University Medical Centre, 3584 CX Utrecht, The Netherlands"},{"name":"ILD Research, Koekoekslaan 1, 3435 CM Nieuwegein, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1725","DOI":"10.2174\/0929867323666160418114600","article-title":"Structure and Expression of Different Serum Amyloid A (SAA) Variants and their Concentration-Dependent Functions During Host Insults","volume":"23","author":"Gouwy","year":"2016","journal-title":"Curr. 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