AUTHOR=Liu Jiajia , Hu Guangli , Liu Shengjin , Ren Guangcai , Gao Liguo , Zhao Zhiqing , Geng Rui , Wang Dingli , Shen Xiao , Chen Feng , Shen Hanqin TITLE=Evaluating passive immunity in piglets from sows vaccinated with a PEDV S protein subunit vaccine JOURNAL=Frontiers in Cellular and Infection Microbiology VOLUME=Volume 14 - 2024 YEAR=2025 URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2024.1498610 DOI=10.3389/fcimb.2024.1498610 ISSN=2235-2988 ABSTRACT=Porcine epidemic diarrhea virus (PEDV) is a highly contagious virus that causes severe diarrhea and high mortality in neonatal piglets. Current control measures, such as inactivated and live-attenuated vaccines, have limitations in providing complete protection. In this study, we evaluate the immunogenicity and protective efficacy of a PEDV S protein subunit vaccine compared to a traditional inactivated vaccine. Piglets and Sows were immunized with either the subunit vaccine or an inactivated vaccine, and serum samples were collected to assess IgG and neutralizing antibody levels. Results demonstrated that the S protein subunit vaccine induced significantly higher IgG and neutralizing antibody levels in both piglets and sows compared to the inactivated vaccine. Piglets born to immunized sows were challenged with a virulent PEDV strain. Piglets from the subunit vaccine group exhibited lower viral shedding, reduced clinical symptoms, and minimal intestinal lesions. These findings suggest that the PEDV S protein subunit vaccine provides enhanced immunity and protection against PEDV, making it a promising candidate for preventing PEDV infections in swine.