本试剂盒应用双抗体夹心酶标免疫分析法测定标本中CT-1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CT-1抗原、生物素化的抗人CT-1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CT-1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 CT-1 concentrations in cell culture supernates, serum, and plasma.
Introduction
Cardiotrophin-1 (CT-1) is a member of the cytokine family which also includes IL-6, IL-11, leukemia inhibitory factor (LIF), oncostatin M (OSM), and ciliary neurotrophic factor (CNTF). It was originally isolated based on its ability to induce cardiac myocyte hypertrophy in vitro. CT-1 has since been shown to be a pleiotrophic cytokine with overlapping actions with other IL-6 family members on a variety of cell types. Human CT-1 encodes a 201 amino acid (aa) residue protein that lacks a hydrophobic signal peptide. The mechanism of CT-1 release from cells is currently not understood. Human and mouse CT-1 share 80% aa sequence identity and exhibit cross-species activity. CT-1 is highly expressed in heart, skeletal muscle, liver, lung and kidney. Lower levels of CT-1 expression is also seen in testis and brain. CT-1 initiates downstream signaling pathways through the heterodimerization of gp130 and the LIF receptor β subunit. A third α receptor subunit has recently been implicated in the receptor complex.
Test principle
This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for CT-1 has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any CT-1 present is bound by the immobilized antibody. An enzyme-linked monoclonal antibody specific for CT-1 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 CT-1 bound in the initial step. The color development is stopped and the intensity of the color is measured.
