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Analyte: Cystatin C
Specimen Type: Serum, Inquire for additional option(s)
Optimum Volume: 0.5 mL
Reporting units: ng/mL
Biological or Clinical Significance:
Cystatin C is a small, 13 kDa, non-glycosylated basic protein belonging to the cystatin super-family of cysteine protease inhibitors. Cystatin C is produced by virtually all nucleated cells, and is present in all body fluids investigated. The production rate is constant and is unaltered in inflammatory conditions. In the normal kidney, cystatin C is almost freely filtered through the glomerular membrane and then nearly completely reabsorbed and degraded by the proximal tubular cells. Therefore, the plasma concentration of cystatin C is almost exclusively determined by the glomerular filtration rate (GFR), making Cystatin C an excellent indicator for GFR.
Principle of Test Method:
The cystatin C assay is a solid phase ELISA designed to measure cystatin C in cell culture supernates, serum, plasma, saliva, urine, and human milk. This assay employs the quantitative sandwich enzyme immunoassay technique.
*Please contact PBI for stability information.
1. Beilby J, Divitini ML, Knuiman MW, Rossi E, Hung J. Comparison of cystatin C and creatinine as predictors of cardiovascular events in a community-based elderly population. Clin Chem. 2010; 56:799-804.
2. Gauthier S, Kaur G, Mi W, Tizon B, Levy E. Protective mechanisms by cystatin C in neurodegenerative diseases. Front Biosci (Schol Ed). 2011; 3:541-554.
3. Perkins BA, Krolewski AS. Early nephropathy in type 1 diabetes: the importance of early renal function decline. Curr Opin Nephrol Hypertens. 2009; 18:233-240.
4. Erlandsen EJ, Randers E, Kristensen JH. Evaluation of the Dade Behring N Latex Cystatin C assay on the Dade Behring Nephelometer II System. Scand J Clin Lab Invest. 1999 Feb;59(1):1-8.