Effect Of Nanoemulsion As An Adjuvant On Immunogenicity Of M.RCAg-1,a Multi-epitope Protein Against Plasmodium Falciparum

Malaria,as a kind of insect-borne infectious diseases,is prevalent in tropical and subtropical regions.It known that malaria,AIDS,and tuberculosis are the most infectious diseases in the world.Malaria is still a threat to human health.According to the most recent data from WHO,about 212 million new cases of malaria and 429 thousand deaths.Effective control strategies such as insecticide-treated bed-nets(ITNs)and artemesinin-combination therapies(ACT)have contributed to considerable reductions in malaria incidence.Yet the emergence of parasite resistance to drugs and vector resistance to insecticides makes great challenge for traditional prevention and treatment of malaria.In view of the considerable parasite genetic diversity,highly antigenic variation and diversity,the immune effects were not satisfactory when Plasmodium falciparum erythrocytic stage vaccine candidate were singly or simple combine used.Therefore constructing multi-antigens and multi-epitopes recombinant protein vaccine has some advantages.In previous study,we constructed a polyepitope gene library by using a novel approach named "epitope shuffling" and selected malaria random constructed antigen-1(M.RCAg-1)with high immunogenicity and stability from the library.M.RCAg-1 has been proved having strong immunogenicity and in vitro anti-paratiste efficacy in BALB/C mice,rabbits and NHPs models.And this malaria vaccine candidate has a promising future.Thus,the purpose of this research is to find new adjuvants which can ensure the further clinical observation of M.RCAg-1.On the basis of previous study before,we selected one potential adjuvant,nanoemulsion with 3 doses to increase the immunogenicity of M.RCAg-1.And then evaluate the immunogenicity of M.RCAg-1 in BALB/C mice to find the best adjuvant dose.Our research lays the foundation for the following clinic study of M.RCAg-1.This research mainly made the following progress:1.Nanoemulsion adjuvants with different doses could enhance the mimmunogenicity of M.RCAg-1 in Balb/c mouse.2.The growth inhititory activity of purified IgG of nanoemulsion A formulated with M.RCAg-1 group is 32.6%.And the growth inhititory activity of purified IgG of nanoemulsion A formulated with M.RCAg-I group is 32.7%.3.It was confirmed that nanoemulsion alone was not ideal as a recombinant protein vaccine adjuvant,suggesting the need to add other immunopotentiators.