Evaluation of the Efficacy of a Recombinant Adenovirus Expressing the Spike Protein of Porcine Epidemic Diarrhea Virus in Pigs.

In recent years, many studies have shown that a live recombinant adenovirus vector-based vaccine is a promising new vaccine candidates against viral infection. Therefore, in this study, a new type of recombinant adenovirus expressing spike (S) protein Cavia Recombinant Proteins pig epidemic diarrhea virus (PEDV), RAD-PEDV-S, produced, and characteristics are determined. 

Then, its efficacy as a vaccine candidate was evaluated in pigs 4-week-old. The results showed that protein S can also be expressed at high levels in the RAD-PEDV-S-infected cells and that the viral titers can reach 1 011 PFU / mL. Furthermore, the results of animal experiments show that the RAD-PEDV-S pose a significant response specific PEDV humoral immunity after vaccination (P <0.05). In addition, RAD-PEDV-S provides partial protection for swine against PEDV extremely lethal challenge. 

The results presented in this study demonstrate that the adenovirus vector can be used as a vaccine vector for vaccine development PEDV and a promising new vaccine candidates for the prevention and control of swine epidemic diarrhea (PED) future, but its efficacy still needs to be improved in the future.

Construction and immunological evaluation of a recombinant vaccine expressing Newcastle disease virus highly pathogenic pig reproductive and respiratory syndrome virus GP3 / GP5 protein in pigs.

Highly pathogenic pig reproductive and respiratory syndrome (HP-PRRS) is a significant threat to the pig industry, the vaccination is considered an effective means of prevention and control. Here, we developed two Newcastle disease virus (NDV) Lasota-PRRS vaccine candidate recombinant vectors, rLaSota-GP5 and rLaSota-GP3-GP5, using reverse genetic engineering. 

Both recombinant virus exhibited a high degree of genetic stability after 10 generations in a row in chicken embryos. There are no significant differences in pathogenicity as compared to the parent strain rLaSota in birds, rats and pigs. Recombinant virus can Chicken Recombinant Proteins not be detected in immunized pigs eating environment, but can be detected in the organs and tissues of pigs no more than 10 days after immunization. 

What is important, in contrast with rLaSota-GP5, rLaSota-GP3-GP5 raises both humoral and cellular immune responses are significant in pigs. In particular, neutralizing antibody titers in the group rLaSota-GP3-GP5 is 1.51 times higher than the commercial vaccine group at 42 days post-immunization. At the same time, there are significant differences in the levels of IFN-γ between groups rLaSota-GP3-GP5 and commercial vaccine group