title: Construction and immunological evaluation of truncated hepatitis B core particles carrying HBsAg amino acids 119-152 in the major immunodominant region (MIR).
abstract: Hepatitis B capsid protein expressed in Escherichia coli can reassemble into icosahedral particles, which could strongly enhance the immunogenicity of foreign epitopes, especially those inserted into its major immunodominant region. Herein, we inserted the entire 'α' antigenic determinant amino acids (aa) 119-152 of HBsAg into the truncated HBc (aa 1-144), between Asp(78) and Pro(79). Prokaryotic expression showed that the mosaic HBc was mainly in the form of inclusion bodies. After denaturation with urea, it was dialyzed progressively for protein renaturation. We observed that before and after renaturation, mosaic HBc was antigenic as determined by HBsAg ELISA and a lot of viruslike particles were observed after renaturation. Thus, we further purified the mosaic viruslike particles by (NH4)2SO4 precipitation, DEAE chromatography, and Sepharose 4FF chromatography. Negative staining electron microscopy demonstrated the morphology of the viruslike particles. Immunization of Balb/c mice with mosaic particles induced the production of anti-HBs antibody and Th1 cell immune response supported by ELISPOT and CD4/CD8 proportions assay. In conclusion, we constructed mosaic hepatitis core particles displaying the entire 'α' antigenic determinant on the surface and laid a foundation for researching therapeutic hepatits B vaccines.
authors: National Institute for Viral Disease Control and Prevention, China Center for Disease Control and Prevention, Changbai Road 155, Changping District, Beijing 102206, People's Republic of China.
authors: Qiudong
authors: Q
authors: Su
authors: Yao
authors: Y
authors: Yi
authors: Minzhuo
authors: M
authors: Guo
authors: Feng
authors: F
authors: Qiu
authors: Zhiyuan
authors: Z
authors: Jia
authors: Xuexin
authors: X
authors: Lu
authors: Qingling
authors: Q
authors: Meng
authors: Shengli
authors: S
authors: Bi
mesh_terms: D000818:Animals; D016516:CD4-CD8 Ratio; D004926:Escherichia coli / Q000378:metabolism; D005260:Female; D006512:Hepatitis B Core Antigens / Q000737:chemistry / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000737:chemistry / Q000276:immunology*; D016056:Immunodominant Epitopes / Q000737:chemistry*; D007371:Interferon-gamma / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000378:metabolism; D011487:Protein Conformation; D017510:Protein Folding; D018417:Th1 Cells / Q000276:immunology
chemical_list: D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D016056:Immunodominant Epitopes; D007371:Interferon-gamma
keywords: Entire ‘α’ antigenic determinant; Inclusion body; Mosaic viruslike particles; Th1 cell response; Truncated HBc