Stromal cell-associated markers in inflamed synovial tissue

Stromal cell-associated markers in inflamed synovial tissue refers to a heterogeneous group of proteins expressed by non-immune cells, primarily fibroblast-like synoviocytes (FLS), that undergo phenotypic shifts during chronic joint inflammation. In diseases such as rheumatoid arthritis, these markers—including fibroblast activation protein (FAP), podoplanin (PDPN), and CD90 (THY1)—distinguish specific fibroblast subpopulations that contribute to either bone and cartilage destruction or the recruitment and persistence of inflammatory immune cells (Croft et al., 2019; Nature). The expansion of these stromal subsets leads to the formation of an invasive pannus, which is a hallmark of joint pathology. While individual markers within this group are being investigated as diagnostic tools and therapeutic targets, the phrase itself describes a collective cellular phenotype rather than a single molecular entity (Mizoguchi et al., 2018; Nature Communications). Research into these markers aims to develop 'stromal-targeted' therapies that could provide a more localized treatment approach, potentially avoiding the systemic side effects of traditional immunosuppressants (Wei et al., 2020; Nature).

Other names

Synovial stromal markersFibroblast-like synoviocyte (FLS) markersSynovial fibroblast subset markersInflammatory synovial fibroblast markers

Individual markers within this category are targeted to inhibit cell-to-cell adhesion, deplete pathogenic fibroblast subsets via antibody-dependent cellular cytotoxicity (ADCC), or neutralize signaling pathways that drive synovial hyperplasia (Croft et al., 2019).