[Analysis of CpG motifs in endoflagellar gene (flaB2) and expression vector (VR1012) of leptospiral DNA vaccine].

OBJECTIVE

To provide basis for the exploring of the mechanism and improvement of the efficacy of DNA vaccines, through the analysis of CpG motifs in endoflagellar gene (flaB2) and expression vector (VR1012) of the Leptospiral DNA vaccine.

METHODS

Directed by Kreig's immunostimulatory nucleic acid molecules, we undertook the computer-assisted analysis of the total number and locations of CpG motifs in flaB2 and VR1012 sequences.

RESULTS

The CpG motifs was flanked by two 5'purines and 3'pyrimidines. There were 3 CpG motifs in flaB2 and 11 in VR1012. Four particularly important TGACGTCA and 1 TAACGCCA were located in the 5' end of VR1012.

CONCLUSION

One of the most important consideration in optimizing a DNA vaccine is the appropriate choice of vectors. The essential feature of a plasmid DNA vector includes a transcriptional unit and an adjuvant unit. The adjuvant properties of a plasmid DNA vector are highly influenced by the number of CpG motifs within the plasmid backbone. Our results showed that both flaB2 and VR1012 contain CpG motifs, which are immunostimulatory sequence and can act as adjuvant of DNA vaccines.