Novel vaccines for the treatment of chronic HBV infection based on mycobacterial heat shock protein 70

Vaccine. 2006 Feb 13;24(7):887-96. doi: 10.1016/j.vaccine.2005.12.050. Epub 2006 Jan 18.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Bacterial Proteins / immunology*
  • Bacterial Proteins / isolation & purification
  • Dendritic Cells / physiology
  • HSP70 Heat-Shock Proteins / immunology*
  • HSP70 Heat-Shock Proteins / isolation & purification
  • Hepatitis B Core Antigens / immunology*
  • Hepatitis B Vaccines / therapeutic use*
  • Hepatitis B, Chronic / therapy*
  • Humans
  • Interleukin-12 / biosynthesis
  • Middle Aged
  • Recombinant Fusion Proteins / immunology
  • T-Lymphocytes, Cytotoxic / immunology
  • Tumor Necrosis Factor-alpha / biosynthesis
  • Vaccines, Synthetic / therapeutic use*

Substances

  • Bacterial Proteins
  • HSP70 Heat-Shock Proteins
  • HSP70 protein, Mycobacterium tuberculosis
  • Hepatitis B Core Antigens
  • Hepatitis B Vaccines
  • Recombinant Fusion Proteins
  • Tumor Necrosis Factor-alpha
  • Vaccines, Synthetic
  • Interleukin-12