[Analysis of the antigenicity of the expression product of fusion antigen epitope genes of FMDV].

AIM

From the different recombinants of FMDV antigen epitope, the highest antigenicity one was selected, and that provided research foundation for making researches on FMD plant-based vaccines which could effectively induce cell immune response and be characterized by high eurytopicity.

METHODS

The single-chain DNA of 5 T-cell epitope genes and 2 B-cell epitope genes were synthesized. By gene splicing by overlap extension technique, 5 T-cell epitope genes were fused together into T and 2 B-cell epitope genes were fused together into B. With Ava III and Pst I which produced uniform stickiness terminal, T and B were fused into recombinats in which T and B existed in different position, namely 5'-T-B-T-3', 5'-T-T-B-3' and 5'-B-T-T-3'. With potato X virus expression vector (PVX) every antigen gene (T, B, T-B-T, T-T-B, B-T-T and VP1) was expected to be expressed in leaves of tobacco. RT-PCR analysis and conformed whether all of the antigen genes were transcribed. Indirect ELISA Western Dotblot conformed analysed the antigeni-city of these products.

RESULTS

Every antigen genes were expressed successfully. The different products had different antigenicity, and 5'-T-B-T -3' was highest, 5'-B-T-T-3' was the second, and 5'-T-T-B-3' was lowest, but 5'-T-T-B-3' was higher than VP1, T or B.

CONCLUSION

It is possible that gene engineering vaccine against FMDV with high eurytopicity and the induction of cell-immune response could be obtained by the different fusion ways with T and B cell epitopes existing in different position of recombinats, and that could have effect on immune activity of vaccines.