Interestingly, no antigenic cross-reactivity between PEDV and PDCoV was detected in either virus-infected cells or intestinal tissues using CCIF or immunohistochemistry (IHC) staining (Ma et al., 2016) . The discrepancy of different assays was suggested to result from different sensitivity among immune assays and/or the exposure of hidden epitopes on viral N proteins by protein denaturing steps in the ELISA and Western blot (Ma et al., 2016) . In our laboratory, two pig hyperimmune TGEV Miller antisera (S409 and M20) and one mouse ascites TGEV N protein MAb (14G9.3C) cross-reacted with PEDV in CCIF assays.