Anti ox-LDL ELISA Kit

Sample

Serum or plasma

Species Reactivity

Human

Detection Method

ELISA

Intended Use

This assay kit is an enzyme immunoassay intended for the quantitative determination of ox-LDL antibodies in EDTA-plasma and serum.

Contents of Kit

1. PLATE Microtiter plate, pre-coated 12×8 wells
2. WASHBUF Wash buffer concentrate, 10×, 2×100 ml
3. STD anti ox-LDL standard concentrate, lyophilised 4×1 vial
4. CTRL1 Control, lyophilised (see specification for range) 4×1 vial
5. CTRL2 Control, lyophilised (see specification for range) 4×1 vial
6. CONJ Conjugate concentrate, peroxidase-labelled 1×200 μl
7. SAMPLEBUF Sample dilution buffer, ready-to-use 2×100 ml
8. SUB Substrate (tetramethylbenzidine), ready-to-use 1×15 ml
9. STOP Stop solution, ready-to-use 1×15 ml

Storage

To run the assay more than once, ensure that reagents are stored at the conditions stated on the label. Prepare only the appropriate amount necessary for each run. The kit can be used up to 4 times within the expiry date stated on the label.

Performance Characteristics

Precision and reproducibility
Intra-Assay (n = 40)
The precision (intra-assay variation) was calculated from 40 replicate determinations on each one of three samples.
Inter-Assay (n = 10)
The total precision (inter-assay variation) was calculated from data on 2 samples obtained in 10 different assays.


Analytical Sensitivity
The LoB (limit of blank) was evaluated according to the guideline CLSI EP17-A2 and resulted in 0.0205U/ml.

General Description

Lipid peroxidation is a natural process essential for cell growth. However, when the oxidative stress overwhelms the antioxidative cell defense, the balance is disturbed and enhanced formation of lipid peroxidation products occurs. At present, lipid peroxidation is considered to be one of the basic mechanisms involved in the initiation and progression of many diseases. Various studies have provided evidence that oxidative stress resulting in lipid peroxidation and protein modification is involved in the pathogenesis of atherosclerosis and coronary heart disease.

Lipid peroxidation products are formed during normal cell metabolism via producing an excess of free radicals that can react with unsaturated fatty acids, in particularly low-density lipoprotein (LDL), the major carrier of plasma cholesterol. LDL is eliminated by macrophages. Normally, receptor-mediated uptake of LDL is suppressed through down-regulation of LDL receptor expression in response to increasing cholesterol levels. Once LDL is oxidised, it is still internalised by macrophages but through scavenger receptors whose expression is not controlled by cholesterol loading. The binding of oxidised LDL (ox-LDL) is the step by which cholesterol accumulation in macrophages is induced transforming them into lipid-loaded 'foam cells'. This process is accompanied by extensive cell proliferation and elaboration of extra cellular matrix components and contributes to the genesis and progression of atherosclerosis by promoting endothelial damage and amplifying the inflammatory response within the vessel wall. Cholesterol-loaded macrophage 'foam cells' are present in the earliest detectable atherosclerotic lesions, the precursor of more complex atherosclerosis that cause stenosis and limited blood flow. These advanced lesions ultimately represent the sites of thrombosis leading to myocardial infarction.

Oxidised LDL is not only an essential trigger of arteriosclerosis and vascular ageing. When modified by the oxidation LDL becomes immunogenic. Specific auto antibodies against epitopes (e.g. malondialdehyde-Lysine) of oxidised LDL in serum have been detected. Auto antibodies against oxidised low density lipoprotein have been found in sera of patients with a number of different symptoms, like diabetes, vascular diseases, carotid arteriosclerosis and others. The ox-LDL antibodies recognise tissues with atherosclerotic lesions. The titer of oxidised LDL antibodies is considered as an independent indicator for the progress of atherosclerosis.

General Notes

This assay kit is an enzyme immunoassay intended for the quantitative determination of ox-LDL antibodies in EDTA-plasma and serum.