Measurement of proteoglycans, elastase, collagenase and protein in synovial fluid in inflammatory and degenerative arthropathies

Abstract

The number of leucocytes and the concentrations of protein, proteoglycans (PG), elastase a1 proteinase inhibitor complexes (E-alpha 1 Pi) and collagenolytic activity were measured in the synovial fluid (SF) of 15 patients with rheumatoid arthritis (RA) and 18 with osteoarthritis (OA). The mean levels of protein, E-alpha 1 Pi and collagenase and the number of leucocytes were higher in RA than in OA SF. However, the mean level of PG was higher of OA SF than in RA. In the latter, they were principally in the form of monomers and fragments while in the former they were in the form of aggregates and monomers. There was a direct relationship between the concentration of E-alpha 1 Pi and either the number of white cells or the concentration of synovial proteins, suggesting that the measurement of E-alpha 1 Pi complexes is a biochemical index of the local inflammatory reaction. There was an inverse correlation between the concentrations of PG and E-alpha 1 Pi which may reflect the effect of degradation in PG of elastase and other enzymes released at the same time. Finally, there was a direct relationship between the concentration of E-alpha 1Pi and collagenase which may be the reflection of a simultaneous release of various enzymes from leucocytes and macrophages.

The Detection, Quantification and Partial Characterisation of Cathepsin B-Like Activity in Human Pathological Synovial Fluids

“…Additionally, inflammation of the synovium may also cause an influx of such cells äs macrophages which may also be responsible for the secretion of cathepsin B and other proteases into the synovial fluid. It is known, for example, that collagenase levels are elevated in diseased, particular inflammatory, conditions again suggesting that proteolytic degradation may play an important role in arthritic disease (32). Cathepsin B has also been identified by other workers in rheumatoid synovial fluid (31) and also in synovial fluid with various forms of arthritis (33), using immunochemical methods.…”

Cartilage proteoglycans in synovial fluid and serum in patients with inflammatory joint disease. relation to systemic treatment

“…Those methods lack the specificity of our assay, and meaningful comparisons of results are therefore precluded. However, Gysen and coworkers (22), using a radioimmunoassay to study synovial fluid proteoglycan concentrations in RA patients, found that the mean concentration was 12.6 pg/ml (n = 15). That result is consistent with our findings.…”

The Effect of Synovial Fluid Enzymes on the Biodegradability of Collagen and Fibrin Clots

“…Synovial fluid is composed of hyaluronan and D-N-acetylglucosamine, as well as many enzymes [15–17], among them matrix metallopeptidase 1 (MMP-1), elastase and plasmin, found in the synovial fluid at varying concentrations [18–20]. These three enzymes are hypothesized to affect the healing of intra-articular injuries [21–28].…”