Macrophage proliferation distinguishes 2 subgroups of knee osteoarthritis patients

• DOI: 10.1172/jci.insight.125325
• Publication Date: 2019-01-23T16:01:58Z
• Authors: Matthew J. Wood; Adam Leckenby; Gary Reynolds; Rachel Spiering; Arthur G. Pratt; Kenneth S. Rankin; John D. Isaacs; Muzlifah A. Haniffa; Simon Milling; Catharien M.U. Hi...
• Keywords: Pathogenesis; CD163; Synovial joint

Osteoarthritis (OA) is a leading cause of disability, globally. Despite an emerging role for synovial inflammation in OA pathogenesis, attempts to target therapeutically have had limited success. A better understanding the cellular and molecular processes occurring synovium needed develop novel therapeutics. We investigated macrophage phenotype gene expression tissue inflammatory-arthritis (IA) patients. Compared with IA, contained higher but variable proportions macrophages (P < 0.001). These exhibited activated phenotype, expressing folate receptor-2 CD86, displayed high phagocytic capacity. RNA sequencing revealed 2 subgroups. Inflammatory-like (iOA) are closely aligned IA characterized by cell proliferation signature. In contrast, classical (cOA) display cartilage remodeling features. Supporting these findings, when compared cOA, iOA 0.01), levels marker Ki67 0.01). data provide new insight into heterogeneity suggest distinct roles pathogenesis. Our findings could lead stratification patients suitable disease-modifying treatments identification therapeutic targets.