Novel vaccines for the treatment of chronic HBV infection based on mycobacterial heat shock protein 70.
Immunogenic peptide-based vaccines can raise significant cellular immune responses. Although cytotoxic T lymphocytes (CTL) peptide epitopes are generally poor immunogens, heat shock protein 70 from Mycobacterium tuberculosis (TBhsp70) can overcome this problem since it is a potent adjuvant that links innate and adaptive immune responses. Our goal is to use TBhsp70 as an adjuvant for development of therapeutic vaccines for chronic Hepatitis B virus infection (HBV). To this end, we genetically fused the HBV core 18-27 peptide (HBcAg((18-27))) as a CTL epitope to the C-terminus of TBhsp70 and expressed the resulting protein in methylotropic yeast Pichia pastoris GS115. At the same time, the TBhsp70-HBcAg((18-27)) peptide complex was reconstituted in vitro. We investigated whether TBhsp70-peptide complex and TBhsp70-peptide fusion protein could generate antigen specific CTL responses in vitro. Dendritic cells (DC) from HLA-A2(+) chronic HBV infection and healthy control pulsed with two vaccines were studied phenotypically by FACS analyses and functionally by cytokine release, and HBV-specific CTL response. Our results demonstrate that two vaccines can activate DC of chronic HBV infection and healthy control by upregulation CD40 and CD86, high production of IL-12p70 and TNF-alpha. Furthermore, autologous T cells with DC stimulated by two vaccines can produce IFN-gamma and generate HBV-specific CTL response. However, capacity for CTL response and cytokines production from HBV infections remained inferior to that of healthy controls. Thus, the strategy of utilizing TBhsp70 may provide a novel design for the development of prophylactic and therapeutic vaccines.
Peng
Mingli
M
Key Laboratory of Molecular Biology for Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Chongqing University of Medical Sciences, PR China. minglip55@yahoo.com.cn
Chen
Min
M
Ling
Ning
N
Xu
Hongmei
H
Qing
Yuling
Y
Ren
Hong
H
D000293:Adolescent; D000328:Adult; D001426:Bacterial Proteins / Q000276:immunology* / Q000302:isolation & purification; D003713:Dendritic Cells / Q000502:physiology; D018840:HSP70 Heat-Shock Proteins / Q000276:immunology* / Q000302:isolation & purification; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000627:therapeutic use*; D019694:Hepatitis B, Chronic / Q000628:therapy*; D006801:Humans; D018664:Interleukin-12 / Q000096:biosynthesis; D008875:Middle Aged; D011993:Recombinant Fusion Proteins / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014614:Vaccines, Synthetic / Q000627:therapeutic use*
D001426:Bacterial Proteins; D018840:HSP70 Heat-Shock Proteins; C444642:HSP70 protein, Mycobacterium tuberculosis; D006512:Hepatitis B Core Antigens; D017325:Hepatitis B Vaccines; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; D014614:Vaccines, Synthetic; D018664:Interleukin-12