DS-MB-01083 detects human Cystatin C, a member of the type 2 cystatin superfamily. Cystatin C is a potent inhibitor of cysteine proteinases, both endogenous (lysosomal cathepsines), and pathogenic. Cystatin C is a 13kDa secreted protein which is found in high concentrations in biological fluids and is thought to be expressed by all human nucleated cells. Changes in cystatin C have been documented in a number of cardiovascular diseases, including atheroslcerosis, amyloid angiopathy and myocardial infarction. Its low molecular weight also means that cystatin C can be used as a marker of renal failure.