{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T14:01:39Z","timestamp":1776952899792,"version":"3.51.4"},"reference-count":33,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T00:00:00Z","timestamp":1620777600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T00:00:00Z","timestamp":1620777600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100000009","name":"Foundation for the National Institutes of Health","doi-asserted-by":"publisher","award":["1K23AR066724"],"award-info":[{"award-number":["1K23AR066724"]}],"id":[{"id":"10.13039\/100000009","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007253","name":"Nancy Taylor Foundation for Chronic Diseases","doi-asserted-by":"publisher","award":["3205042004"],"award-info":[{"award-number":["3205042004"]}],"id":[{"id":"10.13039\/100007253","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Pediatr Rheumatol"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>We examined influences of conditioned media from chondrocytes (Ch) on juvenile idiopathic arthritis synovial fibroblasts (JFLS) and potential for JFLS to undergo endochondral bone formation (EBF).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>Primary cells from three control fibroblast-like synoviocytes (CFLS) and three JFLS were cultured in Ch-conditioned media and compared with untreated fibroblast-like synoviocytes (FLS). RNA was analyzed by ClariomS microarray. FLS cells cultured in conditioned media were exposed to either TGFBR1 inhibitor LY3200882 or exogenous BMP4 and compared with FLS cultured in conditioned media from Ch (JFLS-Ch). Media supernatants were analyzed by ELISA.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>In culture, JFLS downregulate BMP2 and its receptor BMPR1a while upregulating BMP antagonists (NOG and CHRD) and express genes (MMP9, PCNA, MMP12) and proteins (COL2, COLX, COMP) associated with chondrocytes. Important TGF\u03b2 superfamily member gene expression (TGFBI, MMP9, COL1A1, SOX6, and MMP2) is downregulated when JFLS are cultured in Ch-conditioned media. COL2, COLX and COMP protein expression decreases in JFLS-Ch. BMP antagonist protein (NOG, CHRD, GREM, and FST) secretion is significantly increased in JFLS-Ch. Protein phosphorylation increases in JFLS-Ch exposed to exogenous BMP4, and chondrocyte-like phenotype is restored in BMP4 presence, evidenced by increased secretion of COL2 and COLX. Inhibition of TGFBR1 in JFLS-Ch results in overexpression of COL2.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>JFLS are chondrocyte-like, and Ch-conditioned media can abrogate this phenotype. The addition of exogenous BMP4 causes JFLS-Ch to restore this chondrocyte-like phenotype, suggesting that JFLS create a microenvironment favorable for endochondral bone formation, thereby contributing to joint growth disturbances in juvenile idiopathic arthritis.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12969-021-00556-8","type":"journal-article","created":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T18:03:00Z","timestamp":1620842580000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["The culture microenvironment of juvenile idiopathic arthritis synovial fibroblasts is favorable for endochondral bone formation through BMP4 and repressed by chondrocytes"],"prefix":"10.1186","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2685-2645","authenticated-orcid":false,"given":"Megan M.","family":"Simonds","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amanda R.","family":"Schlefman","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Suzanne M.","family":"McCahan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kathleen E.","family":"Sullivan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carlos D.","family":"Rose","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anne Marie C.","family":"Brescia","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2021,5,12]]},"reference":[{"issue":"5","key":"556_CR1","doi-asserted-by":"publisher","first-page":"778","DOI":"10.1002\/1529-0131(199805)41:5<778::AID-ART4>3.0.CO;2-V","volume":"41","author":"RC Lawrence","year":"1998","unstructured":"Lawrence RC, Helmick CG, Arnett FC, Deyo RA, Felson DT, Giannini EH, et al. 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Patients who underwent clinically indicated arthrocentesis were offered inclusion into the repository and informed consent and assent was obtained.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"Not applicable.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"72"}}