Project description:Enterovirus A71 (EV-A71), a causative virus of hand, foot, and mouth diseases, primarily infects and replicates in the intestine and, in severe cases, spreads to the central nervous system (CNS), leading to neurological complications. Therefore, suppressing viral replication in the intestine is important to prevent severe complications. However, the intestinal pathophysiological changes in EV-A71-infected patients remain poorly understood. In this study, we aimed to examine the intestinal response to EV-A71 infection using the intestinal microphysiological system (MPS) we previously developed using human pluripotent stem cells and microfluidic devices. The viral RNA was detectable in the cell culture supernatant of the intestinal MPS for 14 days after the viral infection. Despite this, EV-A71 infection did not induce significant morphological changes in the intestinal MPS and alter the expression of epithelial cell markers, suggesting that the virus can infect the intestinal MPS without causing intestinal epithelial damage. In addition, we found that the secretion of interferons (IFNs) in the cell culture supernatant was not increased by viral infection. Interestingly, the treatment with recombinant IFNs increased the expression of innate immune response-related genes and reduced viral mRNA levels. A strong association was observed between EV-A71 infection and IFN signaling in the intestinal MPS. We believe that the intestinal MPS would be a valuable platform for studying EV-A71 infection and evaluating antiviral strategies.
Project description:RNA interference (RNAi) is an antiviral immunity conserved in diverse eukaryotes including mammals, while viruses encodes viral suppressors of RNAi (VSRs) as countermeasures. However, the physiological impact of RNAi on viral infection in mammals has not been fully assessed, and it also remains unknown whether antiviral RNAi can be therapeutically exploited. Here, we show that peptides designed to target enterovirus A71 (EV-A71)-encoded protein 3A, a well-characterized VSR, triggered an effective antiviral response. These VSR-targeting peptides, particularly ER-DRI, abrogated the VSR function of 3A, which enabled EV-A71-derived siRNA production and unlocked RNAi response that potently inhibited EV-A71 infection in mammals. ER-DRI treatment elicited a strong in vivo antiviral RNAi response that protected mice against lethal EV-A71 challenge. It also potently inhibited another enterovirus, Coxsackievirus-A16, dependently of RNAi. Our findings demonstrate that antiviral RNAi does have a physiologically important impact in mammals and targeting VSRs is a promising strategy for antiviral therapies.
Project description:To elucidate alterations in immune cells during enterovirus 71 (EV-A71) infection and explore potential interaction mechanisms.Single-cell sequencing technology was used to sequence peripheral blood monocytes (PBMCs) obtained from a severe hand, foot and mouth disease (HFMD) patient due to EV-A71 and a healthy control.