Fig. 5. Western blot of the hepatitis E virus (HEV) 110-610 C-end His-tag protein, probed with ELISA negative swine sera from this study (lanes 1–4), and with positive serum (lane 5). M, protein marker. Swine sera recognized a protein band of 54.6 kDa (arrow). Four HEV negative swine sera previously characterized by commercial kit were used as control for western blot specificity (data not shown).