Modeling human enterovirus A71 infection using an intestinal microphysiological system

Enterovirus A71 (EV-A71), a causative virus of hand, foot, and mouth disease, primarily infects and replicates in the intestine and, in severe cases, spreads to the central nervous system, 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 titers were 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 or 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, 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.IMPORTANCEEnterovirus A71 (EV-A71), a major cause of hand, foot, and mouth disease, primarily replicates in the intestine and can spread to the central nervous system, causing severe neurological complications. Suppressing intestinal replication is therefore critical, yet the intestinal pathophysiology of EV-A71 remains poorly understood. Here, we examined EV-A71 infection using a human pluripotent stem cell-derived intestinal microphysiological system (MPS). Viral titers were detectable in the culture supernatant for 14 days. However, EV-A71 did not induce significant morphological changes or alter epithelial marker expression, indicating persistent infection without intestinal damage. Additionally, EV-A71 infection did not enhance interferon (IFN) secretion. Treatment with recombinant IFNs increased innate immune gene expression and reduced viral mRNA, demonstrating the key role of IFN signaling in restricting infection. These findings suggest that the intestinal MPS would be a useful platform for studying EV-A71 infection and antiviral strategies.