title: Enzyme-linked immunosorbent assays for insulin-like growth factor-I using six-histidine tag fused proteins.
abstract: The fusion proteins of insulin-like growth factor-I (IGF-I) and six-histidine tag (IGF-I-6H, 6H-IGF-I-6H) were cloned, expressed, purified and renatured, with their immunoreaction properties and biological activities intact. The binding kinetics between these fusion proteins and anti-IGF-I antibody or anti-6H antibody were studied using surface plasmon resonance (SPR). Two enzyme-linked immunosorbent assay (ELISA) modes, which proved feasible in the measurement of human serum samples, were used to detect IGF-I with the help of the six-histidine tagged proteins. Furthermore, combining the production technique of the six-histidine tagged fusion protein with the competitive sandwich ELISA mode, using an enzyme labeled anti-6H antibody as a tracer, can be a universal immunochemical method to quantitate other polypeptides or proteins.
authors.affiliation: College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
authors.forename: Ruina
authors.initials: R
authors.lastname: Shi
authors.forename: Xuefei
authors.initials: X
authors.lastname: Zhong
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Meiping
authors.initials: M
authors.lastname: Zhao
authors.forename: Yuanzong
authors.initials: Y
authors.lastname: Li
mesh_terms: D000906:Antibodies / Q000276:immunology; D001667:Binding, Competitive; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006639:Histidine / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis* / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D020349:Surface Plasmon Resonance
chemical_list: D000906:Antibodies; D011993:Recombinant Fusion Proteins; D006639:Histidine; D007334:Insulin-Like Growth Factor I