Figure 1  Proliferation of PDCoV in IPEC-J2 cells. (A) Morphological changes in IPEC-J2 cells infected with the PDCoV CHN-HN-1601 strain at an MOI of 0.1 TCID50/cell or mocked infected for 4, 8, 12, 24, and 36 h, respectively. Scale bars, 10 μm. (B) Confirmation of PDCoV proliferation in IPEC-J2 cells by immunofluorescence assays using the mAb 1A3 specific for PDCoV (α-N) and an Alexa Fluor 488-labeled goat antimouse IgG, and mock-infected cells at 24 h was used as a negative control. Cell nuclei were counterstained with DAPI (blue). Scale bars, 10 μm. (C) One-step growth curve of PDCoV in IPEC-J2 cells at the indicated time points following viral infection. The titer of virus was presented as TCID50/mL, and the data were recorded as means ± SD from three independent experiments.