Study Of Nano-emulsion And Herbal Extracts As Influenza Virus Vaccine Adjuvants

Flu refers to influenza, which is an acute respiratory disease caused by the influenza virus. It can spread rapidly and cause serious infections. Influenza vaccination is the best way to prevent the outbreak of an influenza pandemic. There are several flaws of current Influenza virus vaccine. One possible way to solve these problems would be using a potent adjuvant. It can increase their immunogenicity and can reduce the amount of a single dose of flu vaccine. Therefore the use of adjuvants in influenza vaccines can quickly produce enough dose of vaccine when a pandemic flu outbreaks.The first part:the study of nano-emulsion as adjuvant for H3N2 inactivated influenza virus vaccineEmulsion can be used as a vaccine adjuvant, nano-emulsion is the emulsion that particle size less than 100nm. In this study, searching for the safe formula of surfactant, co-surfactant, oil phase and aqueous phase to form a nano-emulsion is the first step. Then using ternary phase diagram to optimize the formula and confirm that EL and Span-80 1:1 mixture as a surfactant, EL-Span-80-1,2 propanediol-Soybean Oil for final nano-emulsion formula. Optimized nano-emulsion can be injected with H3N2 inactivated influenza virus vaccine in Kunming mice. The mice in Nano-emulsion group has a 42d HI titer of 1920, neutralizing antibody titer 447, which are 4 times more than aluminum adjuvant group and vaccine group, and the body weight of normal mice show that nano-emulsion as adjuvant influenza vaccine is both safe and effective. Therefore, nano-emulsion is a good candidate adjuvant for influenza vaccine.The second part:The study of herbal extracts as H3N2 inactivated influenza virus vaccine adjuvantChinese herbal medicine has many traditional advantages. Some Chinese herbal medicine played a key role to control avian influenza and the H1N1 influenza, some herbal extracts that can enhance the immune response is also the consensus among researchers. In this study,40 kinds of herbal extract used as vaccine adjuvant candidates are tested in animals, from which effective adjuvants are screened. Then optimize the 7dose of both vaccine and adjuvant. First of all, the 40 kinds of Chinese herb extracts were mixed with H3N2 inactivated influenza virus vaccine and inoculated mice, after the separation of serum, Cynomorium, turtle shell and Asparaguscochinchinensis can significantly enhance the HI antibody titer compare to all other adjuvant candidates. After the initial screening results, a design to optimize influenza vaccines and Cynomorium extract doses was set, using quadratic rotating test to prove 2.5μg haemagglutinin and 0.8mg Cynomorium is the optimal ratio of Cynomorium and haemagglutinin content. The anticipated HI titer can reach 1778 according to the design, which is basically consistent with the experimental data 1824, proved that the method is reasonable and reliable. Cynomorium has a HI titer up to 1824, neutralizing antibody titer 562,4 times higher than the aluminum adjuvant vaccine group. The body weight of mice increased more than the control group, suggesting that Cynomorium is a safe and efficient adjuvant for influenza vaccine.