PDIA3 and infection: Mice immunized with H3 HA/ERp57 showed less weight loss than those immunized with H3 HA till 7 day post-infection (dpi), especially at 6 dpi (p = 0.0035) (Fig. 6a), indicating that mice immunized with H3 HA/ERp57 showed the better resistance against H1N1 viruses than those immunized with H3 HA.