Immunogenic study of the S protein in mice. A Schematic representation of vaccination schedule in mice. Female mice (N = 6) were vaccinated with 30 μg of purified PEDV/S(1–1320) + CMP + Tags in a micro-emulsion adjuvant (IMS1313). The mice were boosted at 14- and 28-days post-vaccination (dpv), and serum samples were collected at 0, 21, and 42 dpv. B ELISA analysis to detect the increase of PEDV S protein-specific antibodies. All serum samples collected at each time point from each mouse were diluted at 1:50. The OD 450 nm values from each mouse serum are indicated as circles, and the average values are indicated as a bar. C ELISA analysis of the serum dilutions at 42 dpv. All serum samples are diluted from 1:50 to 1:404 800. The OD 450 nm values from each mouse are indicated.