Fig. 3.

ELISA detection of IgG, IgA, and neutralizing antibodies in the serum (A–D) and IgA in fecal samples (E) of weaning piglets experimentally infected with PEDV. ELISA assay based on the PEDV whole virus (WV) or S1 protein was used to measure IgG (A), IgA (B) in serum samples, and IgA in fecal samples (E). Plots represent mean ± SD of 11 samples at each time point. (C) The NA titers were expressed as the reciprocal of the highest serum dilution resulting in the 50% inhibition of PEDV infection relative to controls. (D) Scatter plots showing a correlation between the serum S1-based IgA antibodies and the serum NA (the mean values used for comparison).