Monoclonal expansion of synoviocytes in rheumatoid arthritis

Abstract

Objective. To examine whether synoviocytes from patients with rheumatoid arthritis (RA) have a stronger growth ability than those from patients with osteoarthritis (OA), and to determine whether these synoviocytes clonally expand in situ.Methods. Synovial tissues from 13 KA patients and 4 OA patients were cultured, and their ability to form colonies in soft agarose was examined. RA and OA synoviocytes were also examined in varying concentrations of fetal calf serum (FCS)-containing medium to test the effects of FCS on colony formation. DNA was extracted from clones with colony-forming ability in nonpannus lesions and from synoviocytes in pannus lesions. Restriction fragment length polymorphism (RFLP) analysis was used to examine phosphoglycerate kinase 1 (PGK-1) gene patterns. Production of cytokines by these cells was also assessed.Results. All 13 KA synoviocytes exhibited colony formation, whereas none of the 4 OA synoviocytes did. This tendency was also seen with all of the concentrations of FCS examined, although growth varied in a dose-dependent manner. In contrast to OA synovial clones, cloned M synoviocytes obtained from colonies exhibited a partial KFLP PGK-1 gene pattern, suggesting that the clones originated from monoclonal cells. Of note, 3 of 7 noncloned synoviocytes from pannus lesions

How important are T cells in chronic rheumatoid synovitis?: II. T cell‐independent mechanisms from beginning to end

“…For instance, cells isolated from RA pannus directly eroding cartilage have a distinctive morphology and features of both FLS and chondrocytes ("pannocytes") (71,72). Another study showed that FLS isolated from invasive pannus are oligoclonal, whereas nonerosion FLS are polyclonal (73). Cells from pannus lesions also produce more TGF␤ and platelet-derived growth factor than do those from nonpannus areas, which possibly accounts for their growth advantage.…”

Co‐stimulatory and adhesion molecules of dendritic cells in rheumatoid arthritis

“…Previous reports indicate that immunopathological features of RA ST (including DCs phenotype) reflect clinical disease activity [23][24][25][26]. We compared the expression of costimmulatory and adhesion molecules on DCs in RA patients versus controls with traumatic joint lesions and looked for a possible correlation between the immunophenotypical presentation of DCs and the clinical status of the disease.…”

Inhibition of smoothened decreases proliferation of synoviocytes in rheumatoid arthritis

“…An earlier study reported that FLSs from RA patients expand in a monoclonal fashion and display enhanced growth ability compared to synoviocytes in osteoarthritis (OA). 21 Moreover, the protein levels of cell cycle-related genes, cyclin A and B1 were significantly higher in synovial tissues of RA patients than in those of OA patients or patients with traumatic arthritis. 22 Experiments using adjuvant arthritis in rats have shown that gene therapy with p21/cyclin-dependent kinase-interacting protein 1 (CIP1) inhibits the growth of FLSs and exerts anti-inflammatory effects.…”