预期应用

ELISA法定量测定人血清、血浆或其它相关液体中抗髓过氧化物酶(MPO)抗体含量。

 

实验原理

本试剂盒应用双抗体夹心酶标免疫分析法测定标本中MPO水平。用纯化的抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入MPO抗原、生物素化的抗人MPO抗体、HRP标记的亲和素，经过彻底洗涤后用底物TMB显色。TMB在过氧化物酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。颜色的深浅和样品中的MPO呈正相关。用酶标仪在450nm波长下测定吸光度（OD值），计算样品浓度。

 

Intended use

This immunoassay kit allows for the specific measurement of Human anti-myeloperoxidase antibodies (MPO) concentrations in cell culture supernates, serum and plasma.

 

Introduction

Myeloperoxidase (MPO) is a hemoprotein that is abundantly expressed in polymorphonuclear leukocytes (neutrophils) and secreted during their activation. The presence of a peroxidase in the cytoplasmic granules of leukocytes was suggested at the beginning of 20th century but it was the early 1940s that it was purified for the first time. Native MPO is a covalently bound tetrameric complex of two glycosylated alpha chains (MW 59 – 64 kDa) and two unglycosylated beta chains (MW 14 kDa) with total MW about 150 kDa and theoretical pI 9.2.

MPO plays an important role in neutrophil microbicidal action through catalyzing chloride ion oxidation to hypochlorous acid, which is a potent antimicrobial agent. On the other hand, it was demonstrated that MPO causes oxidative modification of low density lipoprotein (LDL) to a high uptake form that is considered to be a key event in the promotion of atherogenesis. That’s why MPO is believed to participate in the initiation and progression of cardiovascular diseases. MPO possesses potent proinflammatory properties and may contribute directly to tissue injury. In addition,MPO is shown to be involved in pathogenesis of lung cancer , Alzheimer’s disease  and multiple sclerosis .

Now MPO is believed to be one of the most promising cardiac markers. Recently it was demonstrated that an increased MPO level in patient’s blood serves as a risk marker for atherosclerosis and coronary artery disease.It predicts the early risk of myocardial infarction,as well as the risk of other major adverse cardiac events in patients with chest pain in the ensuing 30-day and 6-month periods . The value of MPO as a marker is in that MPO predicts these outcomes independently of other known laboratory tested risk factors, including troponins, creatine kinase MB isoform (CK-MB),C-reactive protein (CRP) and lipid profile.

Moreover, unlike troponins I and T, CK-MB, and CRP, MPO makes it possible to identify patients at risk for cardiac events in the absence of myocardial necrosis. All these factors make MPO measurements in patients an indispensable procedure to reveal patients with chest pain that are at increased risk of cardiovascular complications.

 

Test principle

This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for MPO has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any MPO present is bound by the immobilized antibody. An enzyme-linked monoclonal antibody specific for MPO is added to the wells. Following a wash to remove any unbound antibody-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of MPO bound in the initial step. The color development is stopped and the intensity of the color is measured.