SIZE
96 wells/kit
INTRODUCTION
Human Cystatin c (or cystatin 3), which is composed of 120 amino acid residues, belongs to the cystatins superfamilly that inactivates lysosomal cysteine proteinases. As a strongly cationic and low-molecular weight (13.4 kDa) protein, it is almost freely filtered across the glomerular membrane, and is mainly used as a biomarker of kidney function. A growing body of evidence suggests that cystatin c is a more reliable biomarker of glomerular filtration rate than creatinine [1-3].
In addition to kidney disease, altered serum levels of cystatin c are associated with several types of cardiovascular disease, including myocardial infarction, stroke, heart failure, peripheral arterial disease and metabolic syndrome [4-7]. It also seems to play a role in brain disorders involving amyloid, such as Alzheimer's disease [8, 9]. Furthermore, Cystatin c has also been investigated as a prognostic marker in several forms of cancer.
PRINCIPLE OF THE ASSAY
This assay is a sandwich ELISA designed for the quantitative detection of human cystatin c in samples in 1 hour. The immunoplate is pre-coated with antibody specific to human cystatin c. Standards and samples are pipetted into the wells and any human cystatin c present is sandwiched by the immobilised antibody and a second horseradish peroxidase (HRP)-linked antibody specific to human cystatin c that is co-incubated with the samples. After wash step to remove any unbound substances, the HRP substrate solution is added and colour develops in proportion to the amount of human cystatin c bound initially. The assay is stopped and the optical density of the wells determined using a micro-plate reader. Since the increases in absorbance are directly proportional to the amount of captured human cystatin c, the unknown sample concentration can be interpolated from a reference curve included in each assay.
SIZE
96 wells/kit
INTRODUCTION
Human Cystatin c (or cystatin 3), which is composed of 120 amino acid residues, belongs to the cystatins superfamilly that inactivates lysosomal cysteine proteinases. As a strongly cationic and low-molecular weight (13.4 kDa) protein, it is almost freely filtered across the glomerular membrane, and is mainly used as a biomarker of kidney function. A growing body of evidence suggests that cystatin c is a more reliable biomarker of glomerular filtration rate than creatinine [1-3].
In addition to kidney disease, altered serum levels of cystatin c are associated with several types of cardiovascular disease, including myocardial infarction, stroke, heart failure, peripheral arterial disease and metabolic syndrome [4-7]. It also seems to play a role in brain disorders involving amyloid, such as Alzheimer's disease [8, 9]. Furthermore, Cystatin c has also been investigated as a prognostic marker in several forms of cancer.
PRINCIPLE OF THE ASSAY
This assay is a sandwich ELISA designed for the quantitative detection of human cystatin c in samples in 1 hour. The immunoplate is pre-coated with antibody specific to human cystatin c. Standards and samples are pipetted into the wells and any human cystatin c present is sandwiched by the immobilised antibody and a second horseradish peroxidase (HRP)-linked antibody specific to human cystatin c that is co-incubated with the samples. After wash step to remove any unbound substances, the HRP substrate solution is added and colour develops in proportion to the amount of human cystatin c bound initially. The assay is stopped and the optical density of the wells determined using a micro-plate reader. Since the increases in absorbance are directly proportional to the amount of captured human cystatin c, the unknown sample concentration can be interpolated from a reference curve included in each assay.
