Prediction, recombination and expression of Leptospiral epitopes and analysis of its immunogenicity

Objective: To predict epitopes from two of outer membrane proteins in Leptopspira by bioinformation, and to recombinant, express and analyze recombinant epitopes' immunogenicity. Methods: The prediction programs are ProPred and ANTIGENIC. Recombinant epitope gene was constructed by PCR. The PCR product was then cloned to construct recombinant vector. The gene was induced to express fusion protein in E. coli host strain BL21 (DE3) and the fusion protein was purified. Anti-serum of BALB/c mice immunized with fusion protein was tested by MAT to evaluate the fusion protein's immunogenicity. Results: Two peptides functioning both as MHC binding peptides and B cell epitopes were predicted from each of the two outer mambrane proteins. There was no frame-shift mutation nor base substitution in the sequence. The fusion protein was obtained with the purity over 90%. Results of MAT showed that the anti-serum titer of fusion protein was 75.79, while the anti-serum titer of GST was 10.62. Conclusion: The results confirmes that the recombinant epitope has certain immunogenicity, and it's potential for study on recombining epitopes and subunit vaccine in related protein.