ELISA法定量测定大鼠血清、血浆或其它相关液体中血小板衍化生长因子-BB (PDGF-BB)含量。

本试剂盒应用双抗体夹心酶标免疫分析法测定标本中PDGF-BB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PDGF-BB抗原、生物素化的抗大鼠PDGF-BB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PDGF-BB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。

This immunoassay kit allows for the specific measurement of Rat platelet-derived growth factor-BB,PDGF-BB concentrations in cell culture supernates, serum, and plasma.

The Platelet-Derived Growth Factor (PDGF) family consists of proteins derived from four genes (PDGF-A, -B, -C and -D) that form four disulfide-linked homodimers (PDGF-AA, -BB, -CC, -DD)and one heterodimer (PDGF-AB). These proteins and the related VEGF family proteinsshare the conserved PDGF/VEGF homology domain characterized by a pattern of highly conserved cysteine residues, which form the cysteine knot motif. PDGF-B is synthesized as a pre-pro-protein, which has a signal peptide, a mature region, an N- terminal pro-peptide, and a C-terminal extension. The C-terminal extension contains a conserved cell retention motif that confers retention of the secreted PDGF-BB within the pericellular space. Most cells produce both PDGF-A and B chains. The individual chains are assembled stochastically into disulfide-linked inactive homodimeric or heterodimeric precursors in the endoplasmic reticulum. Within the trans-Golgi network, these precursors then undergo the intracellular proteolytic processing necessary for the secretion of the biologically active mature proteins.

PDGF-A and -B isoforms were originally isolated from platelets, but were subsequently found to be produced by multiple cell types including megakaryocytes, fibroblasts, keratinocytes,vascular smooth muscle cells, endothelial cells, neurons, Schwann cells, and macrophages. The mature mouse PDGF-B chain shares 98%, 89%, and 88% amino acid sequence identity to that of rat, human, and dog , respectively. The mature mouse A and B chains share approximately 57% amino acid sequence homology.

PDGF family proteins regulate diverse cellular functions by binding to and inducing the homo- or heterodimerization of two receptor subunits (PDGF Rα and Rβ). Both subunits belong to the class IIIsubfamily of receptor tyrosine kinases. PDGF-BB can induceα/α, βor/β homodimerization as well as/ heterodimerization.PDGF plays important roles in development and regeneration. The major source of PDGF in blood is from platelets, which releases PDGF into circulation upon platelet activation.

This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal

antibody specific for PDGF-BB has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any PDGF-BB present is bound by the immobilized antibody. An enzyme-linked polyclonal antibody specific for PDGF-BB 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 PDGF-BB bound in the initial step. The color development is stopped and the intensity of the color is measured.