Effects of inactivated porcine epidemic diarrhea virus on porcine monocyte-derived dendritic cells and intestinal dendritic cells

•We report the interaction of UV-PEDV with Mo-DCs in vivo and in vitro.•There is enhancement in the ability of Mo-DCs incubated with UV-PEDV in vitro.•UV-PEDV oral administration enhances the ability of intestinal DCs in vivo.

Porcine epidemic diarrhea (PED) is a serious infection in neonatal piglets. As the causative agent of PED, porcine epidemic diarrhea virus (PEDV) results in acute diarrhea and dehydration with high mortality rates in swine. Dendritic cells (DCs) are highly effective antigen-presenting cells to uptake and present viral antigens to T cells, which then initiate a distinct immune response. In this study, our results show that the expression of Mo-DCs surface markers such as SWC3a+ CD1a+, SWC3a+ CD80/86+ and SWC3a+ SLA-II-DR+ is increased after incubation with UV-PEDV for 24 h. Mo-DCs incubated with UV-PEDV produce higher levels of IL-12 and INF-γ compared to mock-infected Mo-DCs. Interactions between Mo-DCs and UV-PEDV significantly stimulate T-cell proliferation in vitro. Consistent with these results, there is an enhancement in the ability of porcine intestinal DCs to activate T-cell proliferation in vivo. We conclude that UV-PEDV may be a useful and safe vaccine to trigger adaptive immunity.