In the relentless battle against porcine epidemic diarrhea virus (PEDV) and porcine transmissible gastroenteritis virus (TGEV), researchers have made a significant breakthrough that could reshape the landscape of swine health and, consequently, the global pork industry. Led by Mingguo Xu from the College of Animal Science and Technology at Shihezi University in China, a team of scientists has developed subunit vaccines targeting the S1 proteins of both viruses, demonstrating promising results in a mouse model.
PEDV and TGEV are notorious for causing severe economic losses in the swine industry, with high morbidity and mortality rates, particularly among suckling piglets. The economic impact is staggering, with estimates suggesting that PEDV alone has cost the U.S. pig farming industry between $900 million and $1.8 billion. The situation is equally dire in other parts of the world, including China, South Korea, and Vietnam, where outbreaks have led to dramatic increases in piglet mortality.
The study, recently published in Veterinary Sciences, focused on the S1 proteins of PEDV and TGEV, which are crucial for viral entry and immune response. The researchers constructed prokaryotic expression vectors for pCZN1-PEDV S1, pCZN1-TGEV S1, and pCZN1-PEDV S1-TGEV S1, and used these to prepare monovalent, bivalent, and mixed vaccines. The vaccines were then tested on Kunming (KM) mice, with a commercial inactivated vaccine serving as the positive control.
The results were encouraging. All vaccines induced high levels of specific IgG, IgG1, and IgG2a antibodies. Notably, the PEDV S1 + TGEV S1 vaccine induced significantly higher levels of specific IgG and IgG1 compared to the positive control at weeks 2 and 8. “The subunit vaccines not only induced robust humoral immune responses but also demonstrated strong cellular immune responses, as evidenced by elevated IFN-γ levels,” said Mingguo Xu, the lead author of the study. This suggests that the vaccines could provide comprehensive protection against both viruses.
The implications of this research are far-reaching. Traditional vaccines, including inactivated and attenuated live vaccines, have shown limitations in protecting against highly virulent strains and preventing outbreaks. The development of safe and effective subunit vaccines could revolutionize the way we approach PEDV and TGEV infections. “Our findings lay a solid foundation for the development of safe and effective monovalent or bivalent vaccines against PEDV and TGEV,” Xu added. This could lead to reduced economic losses, improved animal welfare, and enhanced food security.
As the global demand for pork continues to rise, the need for effective vaccines becomes increasingly urgent. This research not only addresses a critical gap in swine health but also opens new avenues for vaccine development. The next phase of the study will involve evaluating the immune efficacy of these vaccines in pigs, a crucial step towards commercialization. If successful, these subunit vaccines could become a game-changer in the fight against PEDV and TGEV, offering a more reliable and effective solution for the swine industry.