{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T16:15:52Z","timestamp":1788279352760,"version":"build-2803163510"},"reference-count":4,"publisher":"The Journal of Rheumatology","issue":"Suppl 2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Rheumatol"],"accepted":{"date-parts":[[2026,4,13]]},"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:p>At the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) 2025 annual meeting in Bogot\u00e1, Columbia, Alexandra Khmelevskaya and Dr. Christopher Ritchlin presented a basic symposium on synovial immunopathology. They presented a comparative analysis between rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Their multiomic studies revealed that RA is characterized by heightened intercellular signaling, particularly involving secreted phosphoprotein 1\u2013positive (SPP1+) macrophages, chitinase-3-like protein 1\u2013positive (CHI3L1+) fibroblasts, and fatty acid binding protein 5\u2013positive inflammatory dendritic cell type 3 (FABP5+ iDC3]). Spatial transcriptomics confirmed direct, contact-dependent interactions between SPP1+ macrophages and iDC3 specifically in RA, whereas CHI3L1+ fibroblasts interacted with iDC3 through soluble mediators. Multiplex immunofluorescence validated the tissue localization of these subsets. In contrast, PsA was distinguished by transcriptionally activated CD8+ T cells in both synovium and peripheral blood, with open chromatin states indicating preactivation prior to tissue infiltration. These findings delineate RA-specific stromal-myeloid-dendritic cell networks and PsA-specific T-cell activation programs. Together, they underscore distinct immunopathogenic mechanisms and provide potential targets for precision therapeutics in inflammatory arthritis.<\/jats:p>","DOI":"10.3899\/jrheum.2026-0375","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T12:20:13Z","timestamp":1781526013000},"page":"44-47","source":"Crossref","is-referenced-by-count":0,"title":["Single-Cell and Spatial Omics Uncover Disease-Specific Synovial Landscapes in Rheumatoid and Psoriatic Arthritis"],"prefix":"10.3899","volume":"53","author":[{"given":"Alexandra","family":"Khmelevskaya","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Ritchlin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline","family":"Ospelt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8918-7304","authenticated-orcid":false,"given":"Raphael","family":"Micheroli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2262","published-online":{"date-parts":[[2026,6,15]]},"reference":[{"key":"2026090108201376000_53.Suppl_2.44.1","doi-asserted-by":"publisher","DOI":"10.1016\/j.mam.2024.101276"},{"key":"2026090108201376000_53.Suppl_2.44.2","doi-asserted-by":"publisher","DOI":"10.1038\/s41596-018-0073-y"},{"key":"2026090108201376000_53.Suppl_2.44.3","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1038\/s41584-020-00507-9","article-title":"Applying precision medicine to unmet clinical needs in psoriatic disease","volume":"16","author":"Jadon","year":"2020","journal-title":"Nat Rev Rheumatol"},{"key":"2026090108201376000_53.Suppl_2.44.4","doi-asserted-by":"publisher","DOI":"10.1038\/nrrheum.2015.147"}],"container-title":["The Journal of Rheumatology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.3899\/jrheum.2026-0375","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T15:20:17Z","timestamp":1788276017000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.jrheum.org\/lookup\/doi\/10.3899\/jrheum.2026-0375"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,15]]},"references-count":4,"journal-issue":{"issue":"Suppl 2","published-online":{"date-parts":[[2026,9,1]]},"published-print":{"date-parts":[[2026,9]]}},"alternative-id":["10.3899\/jrheum.2026-0375"],"URL":"https:\/\/doi.org\/10.3899\/jrheum.2026-0375","relation":{},"ISSN":["0315-162X","1499-2752"],"issn-type":[{"value":"0315-162X","type":"print"},{"value":"1499-2752","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,15]]}}}