Human Cystatin C (or Cystatin 3), is composed of 120 amino acid residues and belongs to the Cystatins superfamilly. As a strongly cationic and low-molecular weight (13.4 kDa) protein, Cystatin C freely filters across the glomerular membrane, thus it is mainly used as a biomarker for kidney function.
A growing body of evidence suggests that Cystatin C is a more reliable biomarker of Glomerular filtration rate(GFR) than creatinine for clinical assessment of kidney function. Therefore, Cystatin C is considered to be a potential alternative to serum creatinine for estimating GFR. In addition to kidney disease, altered serum levels of Cystatin C are associated with several types of cardiovascular diseases including myocardial infarction, stroke, heart failure, peripheral arterial disease and metabolic syndrome. Cystatin C is also thought to play a role in brain disorders involving amyloid, such as Alzheimer‘s disease. Currently many researchers are evaluating the role of Cystatin C in otrher diseases like pre-eclampsia and cancer detection.
ImmunoDiagnostics has developed a series of Cystatin C related products, such as ELISA Kits, ITA Assays and Antibodies, which have been used globally for over a decade.
Cystatin C as a measure of renal function overcomes the limitations of using the creatinine level. This is due to its concentration not being influenced by age, sex, or body mass
Sensitivity: The lowest level of human cystatin c that can be detected by this assay is 0.23 ng/ml.
Specificity: The antibodies used in this assay are specific to human cystatin c and do not cross-react with mouse and rat cystatin c, and other cytokine or hormone molecules.
Intra-assay Precision (Precision within an assay) Three samples of known concentration were tested 12 times on one plate.