Thesis (M.Sc.) - Cairo University - Faculty of Pharmacy - Department of Microbiology and Immunology

The best way to prevent hepatitis B is by getting the hepatitis B vaccine. Although the current Hepatitis B vaccine, which contain alum is safe and generally efficacious, still provides some limitations which hinder the goals of controlling the disease worldwide. These trigger the efforts to improve vaccine immunogenicity by developing new adjuvant. In this present study we evaluated the use of Chitosan (Ch), Sodium alginate (S) as safe, nature and effective adjuvant to hepatitis B antigen (HBsAg) alone or combined with alum (Al) by preparing different formulations of Hepatitis B vaccine that were administrated subcutaneously to mice. After 28 days post-immunization, rate of seroconversion, serum HBsAg-specific antibody titers and IL-4, IFN-Þ levels were evaluated. The results showed that Ch and S groups exhibited comparable immunogenic effect as Al group and unadjuvanted group; Moreover Ch group elicited a balanced Th1/Th2 response, while S group shifted the response toward a Th2 pathway. The highest immunogenic response was observed in AlChS group with the highest seroconversion rate, anti-HBsAg IgG titer, IL-4 and IFN-Þ enhancement production, significantly higher than the entire immunized group, while other combined adjuvanted formulations AlCh, AlS gave no additional important benefits. These findings indicated that both Chitosan and Sodium alginate could be a safe and effective adjuvant for Hepatitis B vaccine inducing 10-fold immunogenic response than the same dose of unadjuvanted antigen whether used alone or in combination with Alum

Issued also as CD