S1 domain of the porcine epidemic diarrhea virus spike protein as a vaccine antigen

Makadiya, Niraj; Brownlie, Robert; van den Hurk, Jan; Berube, Nathalie; Allan, Brenda; Gerdts, Volker; Zakhartchouk, Alexander

Expression of the recombinant PEDV S1 protein in HEK 293 T cells. a Cells were grown to confluency in 6 well plates. The DMEM was replaced with serum free medium (either SFM4HEK293; lane 1 or Opti-MEM; lane 2) and incubated further for 24 h before analyzing culture supernatant by Western blotting with anti-his antibody. The S1 was expressed with native signal peptide (S SP) or with TPA signal peptide (TPA SP). A negative control was HEK-293 T cells that had not been transfected. b Analysis of the purified S1 protein by Coomassie Blue staining of SDS-PAGE. Numbers on the left indicate the protein molecular marker size in kDa post-vaccination, and by 28 days the titers had increased 100-fold (Fig. 5b) . In contrast to ELISA titers (Fig. 5a) , virus neutralizing titers did not increase after the third immunization of sow by day 35 (Fig. 5b) .