Figure 4
Adjuvant enhanced vaccine to elicit a hemagglutination inhibition (HAI) antibody response. Mice (n = 7 to 8 per group) were immunized with single different dose of S-OIV H1N1 or NIBRG-14 H5N1 influenza vaccine with or without alum or MPLA as the adjuvant. The titers of serum specific antibodies were evaluated using the hemagglutination inhibition (HAI) test. Data are representative of two separate experiments of H1N1 vaccine immunized mice sera (No sera from H5N1-immunized mice contained HAI to NIBRG-14 H5N1 virus using chicken red blood cells). Comparisons of HAI antibody titer in mice immunized with PBS, 0.001 μg, 0.1 μg, or 0.5 μg of HA in the produced vaccine with or without adjuvant. For comparison of HAI antibody titers, Student’s t test was used to examine the significance of differences between HAI positive rates (with HAI titer 3 40) of each vaccinated group and control group (mice immunized with PBS only). A P value of < 0.05 was considered significant. The star “★” indicates significant differences.