Immunization with porcine epidemic diarrhea virus harbouring Fc domain of IgG enhances antibody production in pigs

Abstract

Background: Outbreaks of porcine epidemic diarrhea virus (PEDV) infection have reemerged and spread rapidly worldwide, resulting in significant economic losses. Vaccination is the best way to prevent PEDV infection in young piglets. Objective: To enhance the efficacy of an inactivated vaccine against PEDV, we evaluated the adjuvant properties of Fc domain of IgG. Methods: Fifteen crossbred gilts (180 $ 210 days old) were used. Five pigs in group 1 were intramuscularly vaccinated twice at 4 weeks and 2 weeks prior to farrowing with 10 6 TCID 50 of inactivated PEDV. Five pigs in group 2 were intramuscularly vaccinated twice at 4 weeks and 2 weeks prior to farrowing with 10 6 TCID 50 of inactivated PEDV-sFc. Five pigs in group 3 were not vaccinated and served as negative controls. Serum samples were collected at farrowing and subjected to ELISA, a serum neutralizing (SN) test, and a cytokine assay. Statistical analysis was performed by a two-tailed unpaired t-test. Results: Vero cells expressing swine IgG Fc on its surface was established. When PEDV was propagated in the cells expressing the swine Fc, PEDV virion incorporated the Fc. Immunization of pigs with inactivated PEDV harbouring Fc induced significantly higher antibody production against PEDV, comparing to the immunization with normal inactivated PEDV. In addition, we observed significantly increased IFN-c levels in sera. Conclusion: Our results indicate that Fc molecule facilitate immune responses and PEDV harbouring Fc molecule could be a possible vaccine candidate. However, a challenge experiment would be needed to investigate the protective efficacy of PEDV harbouring Fc.

The immunogenicity of plant-based COE-GCN4pII protein in pigs against the highly virulent porcine epidemic diarrhea virus strain from genotype 2

“…Notably, the level of IFN-γ in sow (day 35 pi) and its offspring (day 0 pc) were detected at a very high concentration of 932.3 ± 145.2 pg/ml and 824.5 ± 157.68 pg/ml, respectively. When compared to the previous studies, the concentration of IFN-γ in sows vaccinated with COE/G2a-pII at farrowing was over 5-fold higher than that in sows vaccinated with killed-PEDV vaccine plus flagellin protein (Vac201-FliC) ( 31 ) and over 10-fold higher than that in sows vaccinated with inactivated PEDV harboring IgG-Fc ( 35 ). The level of IFN-γ in sow (day 50 pi) and its offspring (day 10 pc) were 2-fold increased in comparison with those before the challenge.…”

Study of the immunogenicity of recombinant protein consisting of multiple epitopes of porcine epidemic diarrhea virus highly expressed in Sf9 cells

“…In recent years, the ongoing epidemic of PEDV has caused signi cant economic losses to the swine industry in Asia as well as Europe and North America [22] . To date, there have been several PEDV commercial vaccines in the market, mainly including inactivated vaccines and attenuated vaccines.…”

B602L-Fc fusion protein enhances the immunogenicity of the B602L protein of the African swine fever virus

“…FcRⅠ plays critical roles in the innate and adaptive immune responses by activating a variety of biological functions, such as processing and presentation of antigens, the release of inflammatory mediators, endocytosis of immune complexes, antibody protection against viral infection, microbial phagocytosis, and antibody-dependent cytotoxicity ( 24 – 26 ). Fc receptors are important mediators of cellular immunity and are also important receptors linking IgG-secreting lymphocytes and phagocytes ( 27 ). Fusion of antigens to Fc fragments is a new vaccine development strategy, which may cause Fc receptor-mediated antigen transport across the membrane barrier, thereby effectively enhancing the humoral and cellular immunities of the body ( 26 ).…”