检测范围:31.2pg/ml-2000pg/ml
预期应用
ELISA法定量测定人血清、细胞培养物上清或其它相关液体中BDNF含量。
概述
脑源性神经营养因子(brain derived neurotrophic factor，BDNF)是1982年德国神经生物学家从猪脑中分离出来的小分子蛋白质，因猪、人、小鼠和人类的BDNF具有完全相同的氨基酸编码序列，且与神经生长因子（nerve growth factor，NGF）序列具有惊人的相似性,故被归属为神经生长因子家族成员。BNDF是由120个氨基酸组成的一种碱性蛋白，是神经营养因子家族成员之一，是由神经元的靶细胞分泌，逆向营养神经元，BNDF对神经细胞的生长发育及保护修复有重要作用,其生物学效应主要由二种类型的跨膜糖蛋白介导，一种是高亲和力受体TrKB，另一种是低亲合力神经营养素受体（LNGFR），其中TrKB是信号转导所必需的。TrKB的细胞外配体结合区与BNDF结合后可发生自磷酸化，继而发生一系列底物磷酸化反应，实现从细胞膜到细胞核的信息传递而引起细胞应答效应, TrKB主要表达在脑中。目前BDNF被认为是抗凋亡剂、抗氧化剂和钙通道阻滞剂。
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BDNF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BDNF抗原、生物素化的抗人BDNF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BDNF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 BDNF concentrations in cell culture supernates, serum, and plasma.
Introduction
BDNF is a 13 kDa, 119 amino acid (aa) residue non-glycosylated polypeptide whose primary structure is conserved among all mammalian species examined. Initially synthesized as a 247 aa residue prepropeptide, the BDNF molecule is divided into an 18 aa residue signal sequence, a 110 aa residue prosequence, and a 119 aa residue mature segment. Similar to other neurotrophic factors, there is a possibility that the N-terminus is alternatively spliced, giving rise to a longer pre-prosegment (but identical mature segment) with different functional properties. As a mature molecule, BDNF is 52% identical to NGF at the amino acid level, exists as a noncovalently-linked homodimer in solution, and contains six cysteine residues that are believed to form three intrachain disulfide linkages. BDNF in plasma is detected in the pg/mL range, while BDNF in serum is measured in the ng/mL range, the difference apparently attributable to platelet degranulation and BDNF release during clotting. The conservation of BDNF structure potentially allows a BDNF ELISA to be widely applied across species.
Test principle
This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal
antibody specific for BDNF has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any BDNF present is bound by the immobilized antibody. An
enzyme-linked monoclonal antibody specific for BDNF 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 BDNF bound in the initial step. The color
development is stopped and the intensity of the color is measured. | 
