Department of Physics, Chemistry and Biology (IFM)

Use of stabilizators in the vaccine in mice from experiment 1 has not greatly enhanced the serum antibody titers when compared to mice that were vaccinated along with adjuvants. The promising results of this study show that the antibody titers are greatly enhanced ~4 fold within four weeks of second and third dose (booster dose). Thus Endocine was found to greatly enhance the IgG and IgA titers both of which play a key role in protection against infection of Influenza virus. Intranasal vaccination is better than the sublingual vaccination in using fewer amounts of antigen and adjuvant. A higher amount of antigen (4.5µg) was used in this study for sublingual vaccination because oral immunization presents a challenge to the antigen due to harsh environment of the intestine. However, in this study sublingual vaccination induced significant antibody titers indicating the potency of Endocine as an adjuvant. The mice of group 2 (Adjuvant) and group 4 (Adjuvant+EDTA) have exhibited some protective HI titers. The most important criteria for a satisfactory response for hemagglutination inhibition are to achieve serum HI titers of ≥40. However the median of HI titers against H1N1 California strain obtained in the mice immunized intranasally in this study were not found to be more than 50, but these are assumed to be protective enough against the disease. Moreover the dose of the antigen used in mice immunized intranasally was very low (1.5µg), a higher dose was expected to elicit a much higher range of HI titers. Unfortunately the mice immunized with a higher dose of 4.5µg (sublingual vaccination) have failed to show any HI titers. The humoral response in terms of cross reactivity was also examined in the mice immunized intranasally against the A/H1N1/Brisbane strain. A good quality of cross protection against the A/H1N1/Brisbane strain has been observed with titers as high as 320.