Diseases affecting the musculoskeletal system are a major cost burden to society. Articular cartilage loss or damage in these diseases is detected by radiography and measuring decreases in joint space width (JSW). The early stages of the disease may remain latent and asymptomatic for many years. This forms the rationale for applying molecular marker technology (biomarkers) to identify patients prone to joint diseases. One such biomarker is cartilage oligomeric matrix protein (COMP, thrombospondin five). COMP can be used to monitor the progress of cartilage degradation in inflammatory joint diseases such as rheumatoid arthritis (RA) and osteoarthritis (OA). Clinical studies have shown that measurements of serum COMP can be used a valuable tool for identifying patients at high risk from rapid joint destruction and for monitoring treatment efficacy.
We report the results of an automated COMP assay on the IDS-iSYS.The COMP assay is based on the direct sandwich technique in which two specific monoclonal antibodies are directed against separate antigenic determinants on the COMP molecule.
Below are the preliminary analytical performance of the IDS-iSYS COMP assay.
|Inter-assay precision||Five samples tested over 12 days gave %CVs between 4 and 9% on dose at concentrations between 10 and 46 μg/ml.|
|Sensitivity||Limit of blank: 0.011 μg/ml; limit of detection: 0.027 μg/ml; limit of quantitation: <0.0625 μg/ml|
|Linearity||Variation being within ±10%|
|Recovery||Eight tests gave a range of 102112%|
|High dose hook effect||No hook effect observed up to 100 μg/ml|
|Method comparison against AnaMar COMP kit||iSYS COMP =1.425×(AnaMar) −0.36 μg/ml R2=0.64|
17 May 2014 - 20 May 2014