Figure 3From: Protection against H1N1 influenza challenge by a DNA vaccine expressing H3/H1 subtype hemagglutinin combined with MHC class II-restricted epitopesImmunofluorescence assays to detect antigens expressed from the HA-based DNA vaccine by immune sera. (A) pV-H3HA detected by H3+ serum, (B) pV-H1HA1 detected by H1+ serum, (C) pV-H3-H1 detected by H3+ serum, (D) pV-H3-H1 detected by H1+ serum, (E) pV-H3-EHA-H1 detected by H3+ serum, (F) pV-H3-EHA-H1 detected by H1+ serum, (G) pV-H3-EHA-H1 detected by H5+ serum. (H) pV-H3-EHA-H1 detected by H7+ serum, (I) pV-H3-EHA-H1 detected by H9+ serum, (J) pVAX1 control group. The BHK cells transfected with recombinant plasmids displayed specific fluorescence at the cell membrane and throughout the cytoplasm, while those transfected with the empty pVAX1 vector control were negative.Back to article page