Studies On A Novel Subunit Epitope Vaccine CTB-Emy162 Against Alveolar Echinococcosis

Objective Constructed a prokaryotic expression system for CTB-Emy162, obtained Purified fusion protein. Establishment of animal model to observe the expected antigenicity and immunogenicity of CTB- Emy162.Method According to the sequence of echinococcus multilocularis Emy162 antigen in Gen Bank, Bioinformatics software OptimumTM Codon was used to obtain a suitable sequence of gene expressed in E.coli BL-21 by optimizing of codon adaptation index(CAI), the optimal codon fre-quency(FOP) and the content of GC. The gene of Emy162 was amplified by PCR and was coupled with cholera toxin B subunit(CTB) by molecular biology techniques to design a scientific and reasonable recombinant gene CTB-Emy162. Constructed the prokaryotic expression plasmid p ET-28a-CTB-Emy162 included Emy162 and CTB gene and transformed into E. coli BL21(DE3). After induced by IPTG, the recombinant protein CTB-Emy162 was purified through NI-NTA and ion exchange chromatography. Based on obtained protein CTB-Emy162, establish the animal model of experimental group and control group: BALB/C mice immunized with CTB-Emy162 is experimental group, BALB/C mice immunized with PBS is control group. Through the molecular biology and immunology method(Spleen lymphoproliferation assay and ELISA) to authenticates the immunogenicity and specificity of subunit vaccine CTB- Emy162.Results The prokaryotic expression vector with target gene CTB-Emy162 was constructed successfully, and obtain the purified recombinant protein CTB-Emy162. CTB-Emy162 has good immunogenicity and antigen activity was confirmed by the molecular biology and immunology method.Conclusion The subunit vaccine CTB-Emy162 of alveolar echinococcosis was expressed successfully using E. coli prokaryotic expression system and has good antigenicity and immune effect. The subunit vaccine CTB-Emy162 probably is an new and ideal vaccine to prevent and treat alveolar echinococcosis.