Serum antibody HA-specific IgG titers detected in sera and BALFs samples by ELISA test.

Mean of serum antibody levels detected in all individuals at time-points 0, 20 PVD and 35 PVD, and 7 dpi of Groups A and B (A) against HA from A/California/04/09(H1N1)pdm09, and (B) against HA from A/Aichi/2/1968(H3N2) are shown. Mean of BALFs antibody levels detected in pigs necropsied at 7 and 14 dpi of Groups A and B (C) against HA from A/California/04/09(H1N1)pdm09, and (D) against HA from A/Aichi/2/1968(H3N2). White circles/bars designate group A (unvaccinated group), and black squares/bars designate group B (pCMV-CTLA4-Ig-NG34 vaccinated group). OD, optical density. PVD, post-vaccination days and Dpi, days post-inoculation. Error bars indicate the mean ± SEM. Statistically significant differences between vaccine treatment groups (P value ppp<0.0001.