Red blood cells serve as a vehicle for PEDV transmission

As the most abundant cell type in the blood, red blood cells (RBCs) are serving for transporting oxygen. However, the mechanism by which RBCs binding virus remains largely unknown. Here, we demonstrated that porcine epidemic diarrhea virus (PEDV), a kind of coronavirus, could hijack RBCs and cause typical diarrhea in neonatal piglets. In an epidemiology investigation of PEDV, the RBCs samples from diarrheic pigs in several pig farms were found to be PEDV-positive. PEDV could bind to neonatal RBCs through CD71 and clathrin-mediated endocytosis, and its viability was maintained for 12 h. PEDV-loaded RBCs could transfer the virus to CD3⁺ T cells by conjugation and reach the intestine mucosa, where it caused infection. Finally, a further animal challenge revealed that transfusing with PEDV-loaded RBCs could cause intestinal epithelial cells (IECs) infection and typical diarrhea symptom. Therefore, our studies illustrated the mechanism by which PEDV could cause intestinal infection through hijacking RBCs, further providing a novel insight into the role of RBCs as potential cells for viral transmission in coronavirus pathogenesis.