title: [Secretory expression and biological activity analysis of an anti-H5 single-chain antibody from Pichia pastoris].
abstract: In our previous study, a panel of 52 broadly cross-reactive H5-specific monoclonal antibodies (MAbs) were generated and characterized. The 13D4, one of these MAbs, has been demonstrated to protect mice against lethal challenge by 4 strains of H5N1 avian influenza virus representing the currently prevailing genetic populations, clades 1, 2.1, 2.2, and 2.3. Here, we further cloned the gene of the 13D4 MAb and constructed a single-chain variable fragment. Then, the 13D4 single-chain antibody (scFv) was expressed in secretory maner in Pichia pastoris. The supernatant of the culture was concentrated and subjected to ammonium sulfate precipitation. The purity of the 13D4 scFv was around 90% in SDS-PAGE following ion-exchange chromatography. We further investigated its binding property using hemagglutination inhibition (HI) test and blocking ELISA. The results indicated that the 13D4 scFv shared the same binding sites and comparable HI titer with the prototype murine 13D4 Mab. In conclusion, an anti-H5 single-chain wide-spectrum neutralizing antibody is prepared successfully in yeast system.
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, Xiamen University, Xiamen 361005, China. hefangping@xmu.edu.cn
authors.forename: Fang-Ping
authors.initials: FP
authors.lastname: He
authors.forename: Qing-Shan
authors.initials: QS
authors.lastname: Lin
authors.forename: Shao-Wei
authors.initials: SW
authors.lastname: Li
authors.forename: Min-Xi
authors.initials: MX
authors.lastname: Wei
authors.forename: Zhen-Qin
authors.initials: ZQ
authors.lastname: Chen
authors.forename: Wen-Xin
authors.initials: WX
authors.lastname: Luo
authors.forename: Yi-Xin
authors.initials: YX
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Ning-Shao
authors.initials: NS
authors.lastname: Xia
mesh_terms: D000914:Antibodies, Viral / Q000235:genetics*; D006385:Hemagglutination Inhibition Tests; D007128:Immunoglobulin Fragments / Q000235:genetics* / Q000276:immunology; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D010843:Pichia / Q000235:genetics*; D057127:Single-Chain Antibodies / Q000235:genetics* / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D007128:Immunoglobulin Fragments; D057127:Single-Chain Antibodies; C055966:immunoglobulin Fv