Antibody Immune Responses Induced By HIV Envelope

Human immunodeficiency virus type 1(HIV-1)has infected or killed more than 70 million people in the past 30 years and threatened human health seriously.AIDS has become a chronic disease from the 'super cancer' because of significant breakthro?gh in antiviral dr?gs,but can not be cured and the patients of AIDS carry virus forever can infect others.Every year millions of people are infected by HIV-1 in world and hundred thousands of people in china.The international consensus is that only a vaccine can effectively control the HIV-1 pandemic.HIV-1 envelope glycoprotein is the sole target of neutralizing antibodies and has been the focus of vaccine research.HIV-1 generates many subtypes during transmission because of high variability.It is difficult to induce broadly neutralizing antibody by immunization in HIV-1 vaccine research.Many research showed that few patients of AIDS can induce broadly neutralizing antibody,and conventional HIV-1 envelope glycoprotein and immunization strategy can not induce potent neutralizing antibody immune response and protective antibody responses.The rational design and optimized immunization strategy of HIV-1 envelope glycoprotein were used to enhance the immunogenicity in this study.The most prevalent CRF07-BC strain in China CN54 was selected as basic immunogen.Comparison of antibody immune responses of different HIV-1 envelope glycoprotein mutants based on EIAV attenuated vaccine was carried out with a DNA prime-protein boost immunization strategy.Polymer,trimer,and monomer of HIV-1 CN54 gp140 protein were isolated and immuned guinea pigs to assess their antibody immune response.In order to induce potent neutralizing antibody immune responses,B'/C,AE and B subtype gp140 protein and HIV-2 gp140 protein were used to study the antibody immune response induced by cross immunization.In order to compare the antibody immune response of two gp140 mutants and wild gp140,corresponding gp140 proteins were purified and immuned to determine the antibody immune responses using a DNA prime-protein boost immunization strategy.The res?lts showed that,compared with wild-type gp 140,gp 140 2M increased env-specific IgG,IgG1,and IgG3 binding antibody titers and gp 140 5M increased env-specific IgG2a,IgG3,and IgA binding antibody titers.Compared with gp 140 2M,gp 140 5M enhanced IgG2a and IgG3 binding antibody titers.There were no significant differences in IgG2b,IgM,V1V2-specific binding antibody,and neutralizing antibody responses.Further analysis showed gpl40 2M induce Thl type immune response and gp140 and gp140 5M induce ThO type immune response.The data showed,compared with gp140 and gp140 5M,gp140 2M induce better binding antibody response and neutralizing antibody response.Gp140 2M may be a better immunogen than gp 140 and gp 140 5M.To study the immunogenicity of different forms of gp140 protein,we used gel exclusion chromatography to isolate polymer,trimer,and monomer of HIV-1 gp140 protein and then immuned them into guinea pigs to assess their immunogenicity.The res?lt showed that the trimer of gp140 induced more potent IgG antibodies and neutralizing antibody against tier 1 HIV-1 pseudovirus.The trimer of gp140 also induce higher level of V1V2 specific IgG binding antibody response and neutralizing antibody against tier 2,tier 3 and NA pseudovirus.The trimer of gp140 may be a better immunogen than polymer and monomer.TheB'/C,AE and B subtype gp140 protein and HIV-2 gp140 protein were used to study the antibody immune response induced by cross immunization.The results showed that,compared with B'/C gp140 immunation alone,both mixed immunity of three subtype HIV-1 and mixed immunity of HIV-1 and HIV-2 enhance the potency and breadth of neutralizing antibody,the binding antibody response against subtype AE and B also were increased.Compared with single subtype immunization,cross immunization induce better binding antibody response and neutralizing antibody response.The immune order of cross immunization can affect antibody immune response.To enhance the protective antibody immune response,we obtain envelope gene in different time from a HIV-1 B subtype patient sample DRVI01 from which a broadly neutralizing antibody DRVIA7 was separated.The gene of envelope was cloned and expressed to study the immunogenicity.Different immune strategy was selected to increase the protective antibody immune responses.The result showed that immune strategy can enhance the neutralizing antibody response in HIV-1 tier 1 pseudovirus,can not increase the neutralizing antibody response in HIV-1 tier 2 pseudovirus.The results showed that the envelope isolated from broadly neutralizing antibody patient can induce neutralizing antibody response against tier 1 pseudovirus and immune order can effect the antibody immune response induced by envelope glycoprotein.