预期应用
ELISA法定量测定鸭血清、血浆、细胞培养物上清、肺泡盥洗液等其它相关液体中IL-8含量。
概述
白细胞介素（IL-8）是1987年首先在受脂多糖刺激的鸭单核细胞培养液上清中分离提纯的一种碱基肝素结合蛋白，具有内源性白细胞趋化和活化作用，最初命名为单核细胞源性中性细胞趋化因子（monocyte-drvived neutrophils chemotactic factor, MDNCF），1998年被正式统一命名为中性粒细胞活化肽/IL-8（NAP/IL-8）。IL-8属于CXC型亚家族，又因其氨基酸第一个半胱氨酸前有谷氨酸-亮氨酸-精氨酸而称为ELR+-CXC型趋化因子。IL-8是一种可由多细胞来源的多功能趋化因子，其生物学功能无种属特异性，除具有特异性使中性粒细胞离开血流游走到炎症组织，脱颗粒，产生超氧阴离子，引起呼吸爆发外，还显示出促血管生成的活性，可参与多种恶性肿瘤的转移及血管生成。此外，IL-8对淋巴细胞和其它免疫细胞也有趋化和活化作用。
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IL-8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IL-8抗原、生物素化的抗鸭IL-8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IL-8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 total duck interleukin 8 (IL-8) concentrations in cell culture supernates, serum , plasma, BALF and other specimen.
Introduction
Interleukin 8 (IL-8), a member of the neutrophil-specific CXC subfamily of chemokines, is a potent neutrophil chemotactic and activating factor. It is a primary inflammatory cytokine produced by many cells (including monocytes/macrophages, T cells, neutrophils, fibroblasts, endothelial cells, keratinocytes, hepatocytes, astrocytes and chondrocytes) in response to proinflammatory stimuli such as IL-1, TNF, LPS and viruses. Its function is, in part, to attract neutrophils to the site of inflammation and to activate them.
The IL-8 cDNA sequence predicts a protein of 99 amino acids. Removal of a 22-residue signal peptide generates a mature protein of 77 amino acids (~ 8 kDa). Further proteolysis of the N-terminal end leads to a variant form with 72 amino acids; full activation of IL-8 may require cleavage to the 72 amino acid form. IL-8 can form non-covalent dimers in solution, especially at high concentrations, but dimerization is not necessary for biological activity.
IL-8 binds to two seven-transmembrane, G protein-coupled receptors, CXCR1 and CXCR2, as well as to the non-signalling Duffy antigen on red-blood cells. The Duffy antigen may play a role in regulating IL-8 activity on functional receptors.
Test principle
This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for IL-8 has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any IL-8 present is bound by the immobilized antibody. After washing away any unbound substances, an enzyme-linked polyclonal antibody specific for IL-8 is added to the wells. Following a wash to remove any unbound antibody-enzyme reagent, an enhanced luminol/peroxide substrate solution is added to the wells and light is produced in proportion to the amount of IL-8 bound in the initial step. A microplate luminometer is used to measure the intensity of the light emitted. | 
