The Role Of HLA ? Gene System In The Antibody Response Induced By JE Inactivated Vaccine And Chronic HCV Infection

Background:The human leucocyte antigen(HLA)system is divided into HLA class I,class III and class II gene regions,which is an important immune system of human.The structure of HLA class II gene region is the most complicated,and classical HLA class II genes include HLA-DR,DQ and DP,which encode products that can present exogenous antigens to CD4+T cells,and activate B cells to differentiate into plasma cells to produce specific antibodies.In this process,the encoded product of the non-classical HLA class II gene HLA-DM regulates the binding of HLA class II molecules to antigenic peptides,thereby affecting the efficiency of antigen presentation.HLA class II genes are highly polymorphic,and their polymorphisms determine the characteristics of HLA class II antigen-binding groove,which affects the presentation of antigenic peptides and is closely related to the immune response of vaccines.Objective:To initially study the molecular mechanism of HLA class II gene system in antigen presentation and immune response,individuals with different antibody levels induced by inactivated Japanese encephalitis vaccine(JEV)were included in the study,then we investigate the role of HLA class ? gene systems in antibody response induced by inactivated JEV,search for HLA molecules associated with inactivated JEV antibody responses.Methods:According to the level of neutralizing antibody,children with JEV vaccination were randomly selected and included in the seropositive group and seronegative group HLA-DRB1,-DQA1,-DQB1,-DPA1,-DPB1 were genotyped by Next-generation sequencing(NGS)typing methods,HLA-DMA and-DMB genes were genotyped by Sanger sequencing and TA cloning,and haplotypes were constructed based on the alleles frequencies.The differences of allele frequencies,haplotype frequencies and anchor residues between the seropositive group and seronegative group were compared.Among the seropositive group,the association between geometric mean titer(GMT)levels and HLA class II alleles groups were compared,and the antigen peptides of HLA II molecules which were associated with antibody responses have been predicted.Results:(1)The frequencies of HLA-DQB1*02:01 was significantly higher in the seropositive group compared to the seronegative group(0.156 vs 0.075,OR=2.267,95%CI:1.285-3.999,P adj=0.018),while the frequencies of DQB 1*02:02 was significantly lower in the seropositive group compared to the seronegative group(0.014 vs 0.095,OR=0.131,95%CI:0.047-0.400,P_adj=0.0002).(2)Haplotype DRB1*07:01-DQA1*02:01-DQB1*02:01-DPA1*01:03-DPB1*04;01(P_adj<0.001)and DQA1*02:01-DQB1*02:01(P_adj<0.001)were only detected in the seropositive group.Haplotype DRB1*07:01-DQA1*02:01-DQB1*02:02-DPA1*02:01-DPB1*17:01(P_adj=0.011)was only detected in the seronegative group.The frequencies of DQA1*02:01-DQB1*02:02(P_adj=0.0003)was significantly higher in the seronegative group.(3)The residue frequencies of DQA1-(-6)-V,DQA1-199-A,DQA1-207-V,DRB1-10,13-QLKF and DRB1-30,32-CIY were significantly higher in the seropositive group compared to the seronegative group(P<0.05).The residue frequencies of DQB1-57-S,DRB1-28-D,DRB1-30-Y was significantly lower in the seropositive group compared to the seronegative group(P<0.05).(4)The GMT levels of the DRB1*11:01 group(1.09±0.232)was significantly lower compared to the DRB1*12:02 group(1.340±0.377)and DRB1*13:02 group(1.400±0.397)(P<0.05);The GMT levels of the DPB1*02:01 group(1.180±0.278)was significantly lower compared to the DPB1*04:01 group(1.32±0.349)and DPB1*05:01 group(1.320±0.367)(P<0.05);The GMT levels of the DPB1*13:01 group(1.040±0.113)was significantly lower compared to the DPB1*04:01 group(1.32±0.349),DPB1*05:01 group(1.320±0.367)and DPB1*09:01 group(1.380±0.357)(P<0.05);The GMT levels of the DQA1*05:05 group(1.15010.226)was significantly lower compared to the DQA1*06:01 group(1.36±0.398).(5)Epitopes binding with DQA1*02:01-DQB1*02:01 dimer is same as DQA1*02:01-DQB1*02:02 dimer.(6)There was no significant difference in the distribution of HLA-DM allele frequencies and haplotype frequencies between the seropositive group and seronegative group(P_adj>0.05).Conclusion:(1)Allele DQB1*02:01,haplotype DRB1*07:01-DQA1*02:01-DQB1*02:01-DPA1*01:03-DPBI*04:01 and DQA1*02:01-DQB1*02:01 were significantly associated with inactivated JEV seropositive,while allele DQB1*02:02,Haplotypes DRB1*07:01-DQA1*02:01-DQB1*02:02-DPA1*02:01:01-DPB1*17:01 and DQA1*02:01-DQB1*02:02 were significantly associated with IJEV seronegative.(2)Anchoring residues DQAl-(-6)-V,DQA1-2-D,DQA1-199-A,DQA1-207-V,DRB1-10-13-QLKF,and DRB1-30-32-CIY were significantly associated with inactivated JEV seropositive,DQB1-57-S,DRB1-28-D and DRB1-30-Y were significantly associated with inactivated JEV seronegative.(3)The groups carrying allele DRB1*11:01,DPB1*02:01,DPB1*13:01 and DQA1*05:05 was significantly associated with lower GMTs of inactivated JEV.While the groups carrying allele DRB1*12:02,DRB1*13:02,DPB1*04:01,DPB1*05:01,DPB1*09:01 and DQA1*06:01 was significantly associated with higher GMTs of inactivated JEV.Objective:To investigate the association between HLA-DM polymorphisms and HCV chronic infection.Methods:185 HCV chronic infectious patients and 180 healthy individuals were recruited in this study.HLA-DMA,DMB genes were genotyped,and the haplotypes were constructed based on HLA-DMA and HLA-DMB alleles.The allele and haplotype frequencies in HCV chronic infection group and healthy control group were calculated and compared to analyze the association between these two groups.Results:There was no significant difference in the distribution of allele frequencies between the two groups(P>0.05).The frequencies of haplotype DMA*01:01-DMB*01:03 was significantly higher in the case group compared to the control group(0.287 vs 0.197,OR=0.134,95%CI:1.529-2.305,P_adj=0.005).Conclusion:Haplotypes DMA*01:01-DMB*01:03 may be associated with susceptibility of chronic HCV infection.