A ferritin-based nanoparticle displaying a neutralizing epitope for foot-and-mouth disease virus (FMDV) confers partial protection in guinea pigs.

BACKGROUND: Foot-and-mouth disease (FMD) is a devastating disease affecting cloven-hoofed animals, that leads to significant economic losses in affected countries and regions. Currently, there is an evident inclination towards the utilization of nanoparticles as powerful platforms for innovative vaccine development. Therefore, this study developed a ferritin-based nanoparticle (FNP) vaccine that displays a neutralizing epitope of foot-and-mouth disease virus (FMDV) VP1 (aa 140-158) on the surface of FNP, and evaluated the immunogenicity and protective efficacy of these FNPs in mouse and guinea pig models to provide a strategy for developing potential FMD vaccines. RESULTS: This study expressed the recombinant proteins Hpf, HPF-NE and HPF-T34E via an E. coli expression system. The results showed that the recombinant proteins Hpf, Hpf-NE and Hpf-T34E could be effectively assembled into nanoparticles. Subsequently, we evaluated the immunogenicity of the Hpf, Hpf-NE and Hpf-T34E proteins in mice, as well as the immunogenicity and protectiveness of the Hpf-T34E protein in guinea pigs. The results of the mouse experiment showed that the immune efficacy in the Hpf-T34E group was greater than the Hpf-NE group. The results from guinea pigs immunized with Hpf-T34E showed that the immune efficacy was largely consistent with the immunogenicity of the FMD inactivated vaccine (IV) and could confer partial protection against FMDV challenge in guinea pigs. CONCLUSIONS: The Hpf-T34E nanoparticles stand out as a superior choice for a subunit vaccine candidate against FMD, offering effective protection in FMDV-infected model animals. FNP-based vaccines exhibit excellent safety and immunogenicity, thus representing a promising strategy for the continued development of highly efficient and safe FMD vaccines.

[Recombinant porcine interferon-gamma expressed in CHO cells and its antiviral activity].

The aim of this study was to produce recombinant porcine interferon gamma (rPoIFN-γ) by Chinese hamster ovarian (CHO) cells expression system and to analyze its antiviral activity. Firstly, we constructed the recombinant eukaryotic expression plasmid pcDNA3.1-PoIFN-γ and transfected into suspension cultured CHO cells for secretory expression of rPoIFN-γ. The rPoIFN-γ was purified by affinity chromatography and identified with SDS-PAGE and Western blotting. Subsequently, the cytotoxicity of rPoIFN-γ was analyzed by CCK-8 test, and the antiviral activity of rPoIFN-γ was evaluated using standard procedures in VSV/PK-15 (virus/cell) test system. Finally the anti-Seneca virus A (SVA) of rPoIFN-γ activity and the induction of interferon-stimulated genes (ISGs) and cytokines were also analyzed. The results showed that rPoIFN-γ could successfully expressed in the supernatant of CHO cells. CCK-8 assays indicated that rPoIFN-γ did not show cytotoxicity on IBRS-2 cells. The biological activity of rPoIFN-γ was 5.59×107 U/mg in VSV/PK-15 system. Moreover, rPoIFN-γ could induced the expression of ISGs and cytokines, and significantly inhibited the replication of SVA. In conclusion, the high activity of rPoIFN-γ was successfully prepared by CHO cells expression system, which showed strong antiviral activity on SVA. This study may facilitate the investigation of rPoIFN-γ function and the development of novel genetically engineered antiviral drugs.