{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T21:20:14Z","timestamp":1792704014209,"version":"4.5.0"},"reference-count":36,"publisher":"American Physiological Society","issue":"4","funder":[{"DOI":"10.13039\/100000050","name":"HHS | NIH | National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["K08HL144820"],"award-info":[{"award-number":["K08HL144820"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"HHS | NIH | National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["HL139860"],"award-info":[{"award-number":["HL139860"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"HHS | NIH | National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["HL110849"],"award-info":[{"award-number":["HL110849"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000069","name":"HHS | NIH | National Institute of Arthritis and Musculoskeletal and Skin Diseases","doi-asserted-by":"publisher","award":["P50 AR060780"],"award-info":[{"award-number":["P50 AR060780"]}],"id":[{"id":"10.13039\/100000069","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["journals.physiology.org"],"crossmark-restriction":true},"short-container-title":["American Journal of Physiology-Lung Cellular and Molecular Physiology"],"published-print":{"date-parts":[[2022,10,1]]},"abstract":"<jats:p> Accumulation of excessive extracellular matrix (ECM) components from lung fibroblasts is a feature of systemic sclerosis-associated interstitial lung disease (SSc-ILD), and there is increasing evidence that innate immune signaling pathways contribute to these processes. Toll-like receptors (TLRs) are innate immune sensors activated by danger signals derived from pathogens or host molecular patterns. Several damage-associated molecular pattern (DAMP) molecules are elevated in SSc-ILD plasma, including ligands that activate TLR9, an innate immune sensor recently implicated in driving profibrotic responses in fibroblasts. Fibronectin and the isoform fibronectin-extra domain A (FN-EDA) are prominent in pathological extracellular matrix accumulation, but mechanisms promoting FN-EDA accumulation are only partially understood. Here, we show that TLR9 activation increases FN-EDA accumulation in MRC5 and SSc-ILD fibroblasts, but that this effect is independent of changes in FN-EDA gene transcription. Rather, we describe a novel mechanism where TLR9 activation inhibits FN-EDA turnover via reduced FN-EDA ubiquitination. TLR9 ligand ODN2006 reduces ubiquitinated FN-EDA destined for lysosomal degradation, an effect abrogated with TLR9 knockdown or inhibition. Taken together, these results provide rationale for disrupting the TLR9 signaling axis or FN-EDA degradation pathways to reduce FN-EDA accumulation in SSc-ILD fibroblasts. More broadly, enhancing intracellular degradation of ECM components through TLR9 inhibition or enhanced ECM turnover could be a novel strategy to attenuate pathogenic ECM accumulation in SSc-ILD. <\/jats:p>","DOI":"10.1152\/ajplung.00019.2022","type":"journal-article","created":{"date-parts":[[2022,8,23]],"date-time":"2022-08-23T12:00:45Z","timestamp":1661256045000},"page":"L484-L494","update-policy":"https:\/\/doi.org\/10.1152\/aps-crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["Fibronectin-EDA accumulates via reduced ubiquitination downstream of Toll-like receptor 9 activation in SSc-ILD fibroblasts"],"prefix":"10.1152","volume":"323","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4225-8627","authenticated-orcid":false,"given":"Ferhan","family":"Tuncer","sequence":"first","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melissa","family":"Bulik","sequence":"additional","affiliation":[{"name":"Division of Rheumatology, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Villandre","sequence":"additional","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9156-0844","authenticated-orcid":false,"given":"Travis","family":"Lear","sequence":"additional","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanwen","family":"Chen","sequence":"additional","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beyza","family":"Tuncer","sequence":"additional","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel J.","family":"Kass","sequence":"additional","affiliation":[{"name":"Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Simmons Center for Interstitial Lung Disease, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleanor","family":"Valenzi","sequence":"additional","affiliation":[{"name":"Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Simmons Center for Interstitial Lung Disease, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Morse","sequence":"additional","affiliation":[{"name":"Division of Rheumatology, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4108-803X","authenticated-orcid":false,"suffix":"2nd","given":"John","family":"Sembrat","sequence":"additional","affiliation":[{"name":"Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Lafyatis","sequence":"additional","affiliation":[{"name":"Simmons Center for Interstitial Lung Disease, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Division of Rheumatology, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bill","family":"Chen","sequence":"additional","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2070-0883","authenticated-orcid":false,"given":"John","family":"Evankovich","sequence":"additional","affiliation":[{"name":"Aging Institute, University of Pittsburgh, Pittsburgh, Pennsylvania"},{"name":"Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1097\/BOR.0b013e32834ff2e8"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1016\/j.clindermatol.2013.01.010"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1016\/j.semarthrit.2008.06.002"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1136\/ard.2006.066068"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1136\/ard.2009.114264"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1186\/ar4230"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1172\/jci.insight.98850"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1007\/s11926-017-0630-3"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1016\/j.imlet.2017.09.001"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1586\/eci.11.40"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.2147\/ITT.S82037"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1146\/annurev-cellbio-100109-104020"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1126\/scitranslmed.3008264"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1038\/jid.2015.155"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1016\/j.addr.2007.12.004"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2013.00037"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1002\/art.39655"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1007\/s10067-017-3880-6"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1126\/scitranslmed.3001510"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0218003"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9440(10)62263-8"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1186\/s12967-015-0588-8"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.3389\/fphar.2017.00264"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1002\/art.41418"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajpath.2014.12.011"},{"key":"B27","volume":"44","author":"Osei ET","year":"2014","journal-title":"Eur Respir J"},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2021.631235"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1186\/rr175"},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1096\/fj.202001607R"},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1038\/jid.2010.200"},{"key":"B32","doi-asserted-by":"publisher","DOI":"10.1016\/j.devcel.2010.06.010"},{"key":"B33","doi-asserted-by":"publisher","DOI":"10.1152\/ajprenal.00157.2002"},{"key":"B34","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M604311200"},{"key":"B35","doi-asserted-by":"publisher","DOI":"10.1042\/BST20160159"},{"key":"B36","doi-asserted-by":"publisher","DOI":"10.1038\/s41577-021-00577-0"},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.1242\/jcs.014977"}],"container-title":["American Journal of Physiology-Lung Cellular and Molecular Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.physiology.org\/doi\/pdf\/10.1152\/ajplung.00019.2022","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,10,4]],"date-time":"2022-10-04T22:09:42Z","timestamp":1664921382000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.physiology.org\/doi\/10.1152\/ajplung.00019.2022"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,10,1]]},"references-count":36,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2022,10,1]]}},"alternative-id":["10.1152\/ajplung.00019.2022"],"URL":"https:\/\/doi.org\/10.1152\/ajplung.00019.2022","relation":{},"ISSN":["1040-0605","1522-1504"],"issn-type":[{"value":"1040-0605","type":"print"},{"value":"1522-1504","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,10,1]]},"assertion":[{"value":"2022-01-18","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-08-17","order":1,"name":"revised","label":"Revised","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-08-18","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-10-04","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}