Human Proprotein Convertase 9/PCSK9 enzyme-linked immunoassay kit（one step）
| Specification | 96 Test |
|---|---|
| Sensitivity | 0.39 ng/ml (50 μl)；0.73 ng/ml (10 μl) |
| Standard Curve Range | 1.37~1000 ng/ml |
| Standard Curve Gradient | 7 Points/3 Folds |
| Number of Incubations | 2 |
| Detectable sample | Liquid phase sample of soluble substances. For example: serum, plasma, cell culture supernatant, tissue grinding liquid, etc. |
| Sample Volume | 50 μl/10 μl |
| Type | Fully Ready-to-Use |
| Operation Duration | 60min |
| ng/ml | O.D. | Average | Corrected | |
|---|---|---|---|---|
| 0.00 | 0.0240 | 0.0258 | 0.0249 | |
| 1.37 | 0.0397 | 0.0364 | 0.0381 | 0.0132 |
| 4.12 | 0.0548 | 0.0582 | 0.0565 | 0.0316 |
| 12.35 | 0.1069 | 0.1131 | 0.1100 | 0.0851 |
| 37.04 | 0.2259 | 0.2386 | 0.2323 | 0.2074 |
| 111.11 | 0.6267 | 0.6424 | 0.6346 | 0.6097 |
| 333.33 | 1.5940 | 1.6130 | 1.6035 | 1.5786 |
| 1000.00 | 4.1244 | 4.1883 | 4.1564 | 4.1315 |
Precision
| Intra-assay Precision | Inter-assay Precision | |||||
| Sample Number | S1 | S2 | S3 | S1 | S2 | S3 |
| 22 | 22 | 22 | 6 | 6 | 6 | |
| Average(ng/ml) | 22.2 | 103.9 | 313.2 | 24.0 | 101.2 | 307.8 |
| Standard Deviation | 0.9 | 6.1 | 18.1 | 1.1 | 5.7 | 11.1 |
| Coefficient of Variation(%) | 4.2 | 5.8 | 5.8 | 3.8 | 5.2 | 5.0 |
Intra-assay Precision (Precision within an assay) Three samples of known concentration were tested twenty times on one plate to assess intra-assay precision.
Inter-assay Precision (Precision between assays) Three samples of known concentration were tested six times on one plate to assess intra-assay precision.
Spike Recovery
The spike recovery was evaluated by spiking 3 levels of human PCSK9 into health human serum sample. The un-spiked serum was used as blank in this experiment.
The recovery ranged from 90% to 117% with an overall mean recovery of 104%.
Sample Values
| Sample Matrix | Sample Evaluated | Range (ng/ml) | Detectable (%) | Mean of Detectable (ng/ml) |
|---|---|---|---|---|
| Serum | 30 | 609.35-1634.60 | 100 | 1146.64 |
Serum/Plasma – Thirty samples from apparently healthy volunteers were evaluated for the presence of PCSK9 in this assay. No medical histories were available for the donors.
Product Data Sheet
Background: Proprotein Convertase 9/PCSK9
Proprotein convertase subtilisin kexin 9 (PCSK9), also named neural apoptosis-regulated convertase 1 (NARC-1), is a member of the proteinase K subfamily of subtilisin-related serine endoproteases. The full-length protein has 692 amino acids, including a signal peptide, a pro- domain, and a catalytic domain. PCSK9 is highly expressed in the liver, intestine, and kidney. It is initially synthesized as a soluble 74 kDa precursor protein. In the endoplasmic reticulum, it undergoes autocatalytic intramolecular cleavage to generate a 14 kDa pro- domain and a 60 kDa catalytic domain. These two domains remain associated when PCSK9 is secreted outside the cells. The primary physiologic function of PCSK9 is to mediate the degradation of low density lipoprotein receptor (LDL R). Early observations indicated that gain-of-function missense mutations in the PCSK9 gene can cause an autosomal dominant form of hypercholesterolemia. The expression of PCSK9 was observed to be up-regulated by the sterol regulatory element binding proteins (SREBPs), a family of transcription factors that are responsible for the upregulation of genes involved in cholesterol and fatty acid metabolism, such as the LDL R gene. Further experimental evidence revealed that in mice, when the PCSK9 gene was knocked out, the number of LDL R in hepatocytes increased, whereas when PCSK9 was over-expressed, the amount of LDL R protein was reduced in the liver. In humans, genetic analyses have shown that individuals who have nonsense or loss-of-function mutations in the PCSK9 gene have significantly lower plasma LDL cholesterol levels. These investigations clearly indicated that PCSK9 plays a key role in reducing the hepatic LDL R levels. Recently, the underlying mechanism has been uncovered: under normal physiologic conditions, the LDL R is internalized on the cell surface and directed to the endosomes in order to be recycled back to the cell surface. PCSK9 binds to the EGF domain of the LDL R and prevents LDL R from being sorted to the endosomes. Instead, the PCSK9/LDL R complex is redistributed to the lysosomes for degradation. As such, PCSK9 regulates the amount of LDL R in the circulation and modulates cholesterol levels. Serum PCSK9 concentrations have been found to be directly associated with cholesterol levels. Since individuals with loss-of-function PCSK9 mutations have strikingly reduced risk of coronary heart diseases, PCSK9 has become an attractive drug target in recent years. One approach is to generate small molecules that are able to interfere with PCSK9 autoactivation and its interaction with LDL R. Other approaches aiming to reduce the amounts of PCSK9 in the circulation, such as small interfering RNAs (siRNAs), have also shown promise.
