Preparation Of Influenza B Virus Hemagglutinin Nanoparticle Vaccine Based On Baculovirus Expression System

Influenza viruses are a serious threat to people’s health because their antigens are prone to mutation and new mutant strains can be produced very easily.There are four types of influenza viruses: A,B,C and D.Influenza B virus(IBV)mainly infects children,the elderly and other immunocompromised groups,and often causes localised outbreaks of influenza,so there is a need to develop a vaccine against it.Haemagglutinin(HA)is one of the two surface glycoproteins of influenza viruses with a major neutralizing antibody recognition site and high immunogenicity,and is the main antigenic protein of subunit protein vaccines.In this study,recombinant baculoviruses with three nanoparticle haemagglutinin proteins were constructed and2 FlubH-Bann was selected for subsequent protein expression and purification.To validate the expressed 2FlubH-Bann protein,a portion of the haemagglutinin protein was expressed using the E.coli expression system and a polyclonal antibody to haemagglutinin was prepared by immunising mice.160 w potency of the polyclonal antibody was detected and the expression of 2FlubH-Bann protein was determined in combination with His primary antibody.2FlubH-Bann protein was purified to form a nanoparticle structure,which was combined Immunisation of mice with aluminium and Cp G adjuvants induced IgG antibodies with a potency of 1:412,000 and neutralising antibodies with a potency of 1:576,whereas immunisation of mice with the monomeric FlubHd protein produced IgG antibodies with a potency of 1:60,900 and neutralising antibodies with a potency of 1:160,respectively.This shows that the nanoparticle vaccine triggered a strong humoral immune response in mice.Thus,polymorphic nanoparticle influenza vaccines used in combination with suitable adjuvants have a high immunogenicity and have great potential for future development.