Prokaryotic Expression Of Truncated VP1 Protein Of Foot-and-mouth Disease Viris Serotype O In Swine And Establishment Of Indirect ELISA

Foot-and-mouth disease (FMD) virus (FMDV) is the etiological agent of an important disease of livestock. It severely decreases livestock production and introduces important trade restrictions on animals and livestock products, it also contributes to severe economic problems of many developing countries. FMD control in endemic areas is implemented by vaccination? Protection against FMD is often associated with the induction of high levels of neutralising antibodies in serum?Detected by serological methods immunized animal serum level of antibodies can be directly evaluated the level of quality of vaccines.In this study, the obtained gene of truncated proteins of VP1 in 131-213 was successfully subeloned into Prokaryotic expression vector 28a-HSP, after sequencing of them was transformed into E. coli BL21(DE3) stran and induced. The SDS-PAGE results showed that the protein mainly existed in the form of inclusion bodies. The recombinant proteins was dealed with urea and an indirect ELISA tesing the antibody against FMDV-O was established using the purified recombinant fusion protein as diagnosis antigen, exhibiting good antigenicity.By comparing the consistency from the established FMDV antibody testing ELISA with the commercial available FMDV antibody testing ELISA from Italy named IZSLER and the commercial available FMDV-O antibody testing ELISA from the republic of Korea named MEDIAN, we randomly choosed 544 samples from field and 235 samples from experimental pigs, the results showed a general conincidence of 89.49%, with 91.83% positive coincidence and 82.36% negative coindence with the established and MEDIAN. Analysising the 235 samples of experimental pigs with the established ELISA and the commercial testing ELISA from Italy and the republic of Korea, the results indicated maternal antibody of FMDV reduced rapidly in piglets and then increased for the positive rate of antibody and the average antibody level, and the antibody level reached a peak after three times of 18 days of immunization, which was consistent with the test results of the kit, However, compared with the kit, HSP-131-ELISA method in the detection of the positive rate of pre-immunization and the first-immunization after 18 days is higher than it and theThe second time immunization is low, sensitivity is higher than that of the kit, and it has a guiding role in the clinical work. In conclusion, the method has high sensitivity, specificity and repeatability, which can provide guidance for the development of ELISA kit for detection of foot and mouth disease.