PEDV transmission assays and conjugate formation
PEDV-loaded RBCs were labeled with CM-Dil Dye, washed extensively to remove unbound virus and dye, and then co-cultured with PBMCs (RBCs: PBMCs = 1:1) for 1 h or 6 h. For detection of PEDV transmission, after co-culture, RBCs were removed by ACK Lysis Buffer and PBMCs were collected to detect by flow cytometry and Western blot. For observation the conjugated formation, CD3+ T cells were purified from PBMCs as described (Li et al., 2018). CD3+ T cells were then co-cultured with virus-loaded RBCs and then centrifuged at 200×g for 5 min. The mixtures of RBCs and PBMCs were detected by flow cytometry and TEM observation.