Figure 6
From: Fusion to chicken C3d enhances the immunogenicity of the M2 protein of avian influenza virus
Titers of antibody against sM2 in SPF chicken serum detected by ELISA. Seventy-five SPF chickens aged 3 weeks were divided into 5 (n = 15) groups. The chickens in the five test groups were immunized thrice with GST-sM2, GST-C3d-L1-C3d-L2-sM2, pcDNA-sM2, pcDNA-C3d-L1-C3d-L2-sM2 and GST-sM2+IFA, respectively. Blood samples were collected before each vaccination and two weeks after the final booster, and antibody against sM2 were detected by ELISA. Ab-positive cut-off values were set as mean + 2 SD of non-immunized sera. An ELISA Ab titer was expressed as the highest serum dilution giving a positive reaction. The titer values were showed in 100 (Log2X ± S).