Human PAI-1 ELISA Kit
Plasminogen activator inhibitor-1 (PAI-1) is the primary inhibitor of tissue-type and urokinase-type plasminogen activator, playing a major role in fibrinolysis . PAI-1 is mainly produced by the endothelium, but is also secreted by other tissue types, such as adipose tissue. It is normally present at low levels in plasma and tissue, but its expression and release increased in various disease states (such as a number of forms of cancer), as well as in obesity and the metabolic syndrome. PAI-1 is also involved in the pathophysiology of renal, pulmonary, cardiovascular, and metabolic diseases. Elevated local or systemic PAI-1 can also exacerbate such pathologic conditions.
PRINCIPLE OF THE ASSAY
This assay is a quantitative sandwich ELISA. The immunoplate is pre- coated with a mouse monoclonal antibody specific for human PAI-1. Standards and samples are pipetted into the wells and any human PAI-1 present is bound by the immobilized antibody. After washing away any unbound substances, a biotin labelled polyclonal antibody specific for human PAI-1 is added to the wells. After wash step to remove any unbound reagents, streptavidin-HRP conjugate (STP-HRP) is added. After the last wash step, an HRP substrate solution is added and colour develops in proportion to the amount of human PAI-1 bound initially. The assay is stopped and the optical density of the wells determined using a microplate reader. Since the increases in absorbance are directly proportional to the amount of captured human PAI-1, the unknown sample concentration can be interpolated from a reference curve included in each assay.
A. Typical Representation of Standard Curve
PAI-1 (ng/mL) Absorbance (450 nm) Blanked Absorbance 0 0.100 0 0.031 0.151 0.051 0.062 0.202 0.102 0.125 0.292 0.192 0.25 0.460 0.360 0.5 0.828 0.728 1.0 1.508 1.408 2.0 2.451
The lowest level of PAI-1 that can be measured by this assay is 0.031 ng/mL.
The antibodies used in this assay are specific to human PAI-1 and do not cross-react with mouse and rat PAI-1, and other cytokine or hormone molecules including human resistin, TNF, ANGPTL4, insulin, leptin and IL6.
Intra-assay Precision (Precision within an assay)
Sample Mean (ng/mL) SD (ng/mL) CV (%) 1 7.51 0.159 2.12 2 2.32 0.070 3.02
Inter-assay Precision (Precision between assays)
Sample Mean (ng/mL) SD (ng/mL) CV (%) 1 0.87 0.036 4.15 2 1.64 0.092 5.63 3 2.93 0.117 3.99 4 4.35 0.204 4.69
Serum samples were spiked with different amounts of human PAI-1 and assayed. The measured concentration of the spiked sample in the assay was compared to the expected concentration. The average recovery was 98%.
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PUBLICATIONS CITING THIS PRODUCT
- Heilbronn LK, Campbell LV, Xu A, Samocha-Bonet D. Metabolically protective cytokines adiponectin and fibroblast growth factor-21 are increased by acute overfeeding in healthy humans. PloS one. 2013 Oct 18;8(10):e78864.
- Wong YK, Cheung CY, Tang CS, Au KW, Hai JS, Lee CH, Lau KK, Cheung BM, Sham PC, Xu A, Lam KS. Age-biomarkers-clinical risk factors for prediction of cardiovascular events in patients with coronary artery disease. Arteriosclerosis, thrombosis, and vascular biology. 2018 Oct;38(10):2519-27.