Project description:Porcine epidemic diarrhea (PED) is an acute, highly contagious, and high-mortality enterophilic infectious disease caused by the porcine epidemic diarrhea virus (PEDV). PEDV is globally endemic and causes substantial economic losses in the swine industry. The PEDV E protein is the smallest structural protein with high expression levels that interacts with the M protein and participates in virus assembly. However, how the host proteins interact with E proteins in PEDV replication remains unknown. We identified host proteins that interact with the PEDV E protein using a combination of PEDV E protein-labeled antibody co-immunoprecipitation and tandem liquid-chromatography mass-spectroscopy (LC-MS/MS).
Project description:Porcine epidemic diarrhea virus (PEDV) has reemerged as the main pathogen of piglets due to its high mutation feature. Monolaurin (ML) is a natural compound with a wide range of antibacterial and antiviral activities. However, the role of ML in PEDV infection is still unknown. This study aimed to evaluate the effect of ML on the growth performance, intestinal function, virus replication and cytokine response in piglets infected with PEDV, and to reveal the mechanism through proteomics analysis. Piglets were orally administrated with ML at a dose of 100 mg/kg·BW for 7 days before PEDV infection. Results showed that although there was no significant effect on the growth performance of piglets, ML administration alleviated the diarrhea caused by PEDV infection. ML administration promoted the recovery of intestinal villi, thereby improving intestinal function. Meanwhile, PEDV replication was significantly inhibited, and PEDV-induced expression of IL-6 and IL-8 were decreased with ML administration. Proteomics analyses showed that 38 proteins were differentially expressed between PEDV and ML+PEDV groups, and were significantly enriched in the interferon-related pathways. This suggests ML could promote the restoration of homeostasis by regulating the interferon pathway. Overall, the present study demonstrated ML could confer a protective effect against PEDV infection in piglets, and may be developed as a drug or feed additive to prevent and control PEDV disease.
Project description:The immune system is thought to be fragile in the neonate, which is susceptible to pathogens. Exosomes are a type of vehicles existing in the body fluid and participate in many biological processes, especially the immune response. Inorder to investigate the roles that exosomes may play during virus infection in the neonate, porcine epidemic diarrhea virus (PEDV), a devastating enteric virus to newborn piglets, was selected for infection. Serum exosomes were then isolated from the newborn-piglets infected or mock-infected with PEDV and followed by a label-free LC-MS/MS based comparative quantitative proteomic analysis. Among 441 proteins detected in the serum exosomes, there were lots of complement proteins. The expression level of the complement C3, C6 and CFB suffered drastic changes due to PEDV infection. After the confirmation by western-blot assay, we then investigated the function of these exosomes on PEDV infection and discovered that the exosomes from mock-infected newborn piglets restricted PEDV infection but this inhibition disappeared after exosomes were heat-inactivated, suggesting that the complement is one of the key antiviral molecules. These findings will facilitate the understanding of the antiviral response of the neonate mediated by exosomes
