Effect Of Nicotinamide Adenine Dinucleotide Combined With Aluminum Hydroxide Or Zink Hydroxide In Immune Response Induced By HBsAg

Hepatitis B virus (HBV) is a major pathogen of acute and chronic hepatitis. HBV infection may result in acute or chronic hepatitis, and may eventually develop to cirrhosis and hepatocelluar carcinomar. HBV belongs to hepadnaviruses family and it is primarily hepatotropic virus and only infects human and chimpanzee, but not non-primate laboratory animals. Despite the development and extensive use of vaccines, hepatitis B virus infection remains an important problem to human health worldwide. In fact, more than5million people world-wide become infected by hepatitis B virus each year, and the WHO has reported over350million carriers of the virus. So developing new HBV vaccine is extremely important.Vaccination with hepatitis B surface (HBsAg) protein has been used for many years to induce protection against HBV infection, which correlated with the induction of neutralizing antibodies (anti-HBs).Though recognized as an effective vaccine, nearly10%of vaccinees with HBsAg fail to develop protective levels of anti-HBsAg antibodies. DNA vaccine could induce antigen-specific cytotoxic T lymphocytes, but it has relatively low efficacy in large animal species and humans. The main point of the failure in HBV vaccine is to induce low immune response. Thus, approaches to improve vaccination efficacy are actively sought.In this study, we choose the NAD combined with aluminum hydroxide and zinc hydroxide as a representative of the genetic adjuvant and investigate the effect of the genetic adjuvant on the effective of immune responses to HBV protein-based vaccines.Polly Matzinger has proposed a novel theory of danger signal model in1994. It was assumed that immune systems take part in discriminating danger signals and non-danger signals. Danger signals released from injuried cells were able to activate antigen-presenting cells and trigger T/B cells effectively and then the relevant immunity was produced. It suggests that danger signals released from injured cells possessed potent adjuvant effects. Endogenous danger signals as adjuvant not only were able to significantly enhance humoral immunity, but also could enhance cellular immunity.So we firstly choose endogenous danger signals-nicotinamide adenine dinucleotide, product of extracellular matrix degradation as one composition of the compound vaccine adjuvant.ICR mice were immunized with HBVs antigen mixed with nicotinamide adenine dinucleotide combined with aluminum hydroxide and zinc hydroxide respectively. HBV antigen group and Zn(OH)2adjuvant group and A1(OH)3adjuvant groupare as controls groups. Anti-HBVs antigen IgG and the conduction of IFN-γ/IL-2and CTL cellular immunity were examined by ELISA and LDH respectively at different time after immunization significance (P<0.05). In the study, we initially get following results:nicotinamide adenine dinucleotide significantly combined with Zn(OH)2/Al(OH)3enhance endogenous anti-HBVs antigen IgG antibody titer and CTL cellular immunity and they are significantly higher than aluminium grou and zinc group(P<0.05) as well as lastet for long time.To judging the sensitization of compound adjuvant, we sensitized the BALB/c mice with the mixture of compound vaccine (the most effective dosage)and100μg the egg albumen. Compared with the aluminum adjuvant group, the IgE level of that group was significantly lower on the8th and14th day after the primary immunity.In conclusion, in this study, we cleary shows that nicotinamide adenine dinucleotide combined with aluminum hydroxide or zinc hydroxide respectively as compound vaccine adjuvant not only could enhance special humoral immunity, but also significantly induce CTL cellular immunity. Our study provides a new method for the research of HBV adjuvant and has established a strong foundation strain for the developing of HBV vaccine.