title: Robust manufacturing and comprehensive characterization of recombinant hepatitis E virus-like particles in Hecolin(®).
abstract: The hepatitis E virus (HEV) vaccine, Hecolin(®), was licensed in China for the prevention of HEV infection and HEV-related diseases with demonstrated safety and efficacy [1,2]. The vaccine is composed of a truncated HEV capsid protein, p239, as the sole antigen encoded by open reading frame 2 and produced using Escherichia coli platform. The production of this virus-like particle (VLP) form of the antigen was successfully scaled up 50-fold from a bench scale to a manufacturing scale. Product consistency was demonstrated using a combination of biophysical, biochemical and immunochemical methods, which revealed comparable antigen characteristics among different batches. Particle size of the nanometer scale particulate antigen and presence of key epitopes on the particle surface are two prerequisites for an efficacious VLP-based vaccine. The particle size was monitored by several different methods, which showed diameters between 20 and 30nm for the p239 particles. The thermal stability and aggregation propensity of the antigen were assessed using differential scanning calorimetry and cloud point assay under heat stress conditions. Key epitopes on the particulate antigen were analyzed using a panel of murine anti-HEV monoclonal antibodies (mAbs). The immuno reactivity to the mAbs among the different antigen lots was highly consistent when analyzed quantitatively using a surface plasmon resonance technique. Using a sandwich ELISA to probe the integrity of two different epitopes in the antigen, the specific antigenicity of multiple batches was assessed to demonstrate consistency in these critical product attributes. Overall, our findings showed that the antigen production process is robust and scalable during the manufacturing of Hecolin(®).
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Minxi
authors.initials: M
authors.lastname: Wei
authors.affiliation: Xiamen Innovax Biotech Co., Xiamen, Fujian 361005, PR China.
authors.forename: Huirong
authors.initials: H
authors.lastname: Pan
authors.affiliation: Xiamen Innovax Biotech Co., Xiamen, Fujian 361005, PR China.
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Kaihang
authors.initials: K
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Zusen
authors.initials: Z
authors.lastname: Weng
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Yibin
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xin
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China.
authors.forename: Shaowei
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: nsxia@xmu.edu.cn.
authors.forename: Ningshao
authors.initials: N
authors.lastname: Xia
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: qinjian_zhao@xmu.edu.cn.
authors.forename: Qinjian
authors.initials: Q
authors.lastname: Zhao
mesh_terms: D000818:Animals; D058846:Antibodies, Monoclonal, Murine-Derived / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology; D036022:Capsid Proteins / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D005260:Female; D016752:Hepatitis E virus; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D010316:Particle Size; D014614:Vaccines, Synthetic / Q000096:biosynthesis* / Q000592:standards; D058425:Vaccines, Virus-Like Particle / Q000096:biosynthesis* / Q000592:standards; D014761:Viral Hepatitis Vaccines / Q000096:biosynthesis* / Q000592:standards
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D000956:Antigens, Viral; D036022:Capsid Proteins; D000939:Epitopes; D014614:Vaccines, Synthetic; D058425:Vaccines, Virus-Like Particle; D014761:Viral Hepatitis Vaccines; C577000:hecolin
keywords: Capsid protein; Hepatitis E virus; Product consistency; Recombinant vaccine; Virus-like particle