A DNA Vaccine Containing Different Influenza Hemagglutinin Epitopes

Hemagglutinin(HA),the surface antigen of influenza virus,is a very important target for influenza DNA vaccines.On the surface of the protein,there are five main neutralizing epitopes that induce protective antibodies against influenza.In this paper,a DNA vaccine was constructed based on the HA1 from the new influenza A(H1N1)virus, which contains two epitopes of the A/PR/8(H1N1) influenza virus HA.Female BALB/c mice were immunized twice by electroporation before challenged with a lethal dose of new influenza A(H1N1) virus or A/PR/8 influenza virus.The result showed that the DNA vaccine could provide mice a complete cross-protection against these two influenza viruses. The protective effects were comparable to those provided bv DNA vaccines containing an intact HA gene.Thus,a DNA vaccine that contains epitopes of different HA genes from influenza viruses of the same subtype could be a new influenza vaccine to offer cross-protection against influenza antigenic drift.