Two oral HBx vaccines delivered by live attenuated Salmonella: both eliciting effective anti-tumor immunity.
Live attenuated bacteria have great potential for use in vaccine development due to several unique advantages, including stable antigen expression, effective antigen presentation, convenient and inexpensive delivery, and low cost of vaccine production. In this study, we expressed hepatitis B virus x gene (HBx) on mouse melanoma cells as the target antigen and constructed Salmonella-based HBx vaccines by two strategies, i.e., recombinant eukaryotic plasmid encoding HBx and a recombinant prokaryotic plasmid encoding Type III secretion system effector-HBx fusion protein. Both HBx constructs elicited significant levels of CTL reaction and IFN-gamma secreting T cells. When mice were challenged with melanoma cells expressing HBx, tumor growth rates in immunized animals were significantly slower than controls. Tumor sizes and tumor weight indices of immunized mice were also significantly lower than controls. We conclude that both strategies described in this study may lead to novel approaches of tumor vaccines.
Wang
Ye-Jun
YJ
Department of Microbiology, Peking University Health Science Center, Beijing, China.
Hou
Yan
Y
Huang
He
H
Liu
Gui-Rong
GR
White
Aaron P
AP
Liu
Shu-Lin
SL
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D017931:DNA Primers; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000276:immunology; D008546:Melanoma, Experimental / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012475:Salmonella / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics*; D054334:Viral Regulatory and Accessory Proteins
D017931:DNA Primers; D017325:Hepatitis B Vaccines; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein