Cystatin C Human Serum Partially Purified
As its name implies, cystatin C is a cysteine protease inhibitor. It is a fairly small protein and is synthesized by most of the cells in the body1. Cystatin C has formerly been referred to as gamma trace because of its migration in the gamma region in electrophoresis2. The low molecular weight of cystatin C means that is readily filtered by the glomerulus, and this, together with its virtually constant production makes cystatin C an excellent indicator of glomerular filtration rate (GFR) and kidney function. Most reports indicate that cystatin C is superior to the more traditional GFR marker, creatinine3-7. Despite this, it has had only limited commercial success and cystatin C has yet to replace creatinine as an indicator of GFR, perhaps due to the greater cost of measurement8. More recently other roles have been discovered for cystatin C. One example is the possible role of cystatin C as a predictor of outcomes in vascular and cardiovascular pathologies9,10,11. Cystatin C also seems to play a role, in perhaps both negative and positive ways, in pathologies involving amyloid deposits12,13,14.
|ADULT SERUM CYSTATIN C REFERENCE RANGE15:
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- 9. Ix, J.H., et. al. Association of Cystatin C with Mortality, Cardiovascular Events, and Incident Heart Failure Among Persons with Coronary Heart Disease. Circulation, 115, 173-179, 2007.
- 10. Alehagen, U. et. al. Cystatin C and NT-proBNP, a Powerful Combination of Biomarkers for Predicting Cardiovascular Mortality in Elderly Patients with Heart Failure: Results from a 10-Year Study in Primary Care. Eur J Heart Fail, 11, 354-360, 2009.
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- 12. Levy, E., et. al. Codeposition of Cystatin C with Amyloid-[beta] Protein in the Brain of Alzheimer Disease Patients. J Neuropathol Exp Neurol, 60, 94-104, 2001.
- 13. Kaeser, S.A., et. al. Cystatin C Modulates Cerebral Î²-Amyloidosis. Nature Genetics, 39, 1437-1439, 2007.
- 14. Mi, W., et. al. Cystatin C Inhibits Amyloid-Î² Deposition in Alzheimer's Disease Mouse Models. Nature Genetics, 39, 1440-1442, 2007.
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