Fusion expression of major antigenic segment of JEV E protein-hsp70 and the identification of domain acting as adjuvant in hsp70.
Hsp70 potentiates specific immune responses to some antigenic peptides fused to it. A recombinant hsp70 protein expression vector in methylotrophic yeast, Pichia pastoris, was developed that fused the major antigenic segment of Japanese encephalitis virus (JEV) E protein to the amino terminus of Mycobacterium tuberculosis hsp70. The C-terminal peptide binding domain of hsp70 stimulated Th1-polarizing cytokines, CC chemokines and an adjuvant effect. However, the N-terminal ATPase domain (hsp70 1-358) failed to stimulate any of these cytokines or chemokines. Based on these data, a vector was constructed that permits the fusion of major antigenic segment of E protein to the amino terminus of peptide binding domain of hsp70. Antibody titers, lymphocytes proliferation, the level of mIL-2 or mIFN-gamma and neutralizing antibodies in immunized mice showed that antigenicity of E-binding domain fusion protein was almost as effective as E-hsp70 fusion protein and more effective than carrier protein hsp70 alone. In eliciting a humoral and cellular immune response, both fusion proteins were more powerful than the major antigenic segment of E protein alone, but less effective than the segment administered with Freund's adjuvant.
Ge
Fei-fei
FF
Key Laboratory of Animal Disease Diagnosis and Immunology, Ministry of Agriculture at Nanjing Agricultural University, Nanjing 210095, China.
Qiu
Ya-feng
YF
Gao
Xiao-fei
XF
Yang
Yao-wu
YW
Chen
Pu-yan
PY
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D004664:Encephalitis Virus, Japanese / Q000235:genetics / Q000276:immunology*; D005260:Female; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology; D009500:Neutralization Tests; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology
D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D018840:HSP70 Heat-Shock Proteins; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D011993:Recombinant Fusion Proteins; D014759:Viral Envelope Proteins; C080628:glycoprotein E, Japanese encephalitis virus; D007371:Interferon-gamma