抗肾小球基底膜GBM病

抗肾小球基底膜(GBM)病,1,抗GBM病的背景,抗GBM病：循环中出现抗GBM抗体、脏器中沉积为特征的自身免疫病1919: Goodpasture首先报道1例18岁男性病人，咯血、急性肾衰竭主要累及肺和肾脏：Goodpasture病内科危重症：危及生命80%就诊时已进入尿毒症（ESRD）,2,Goodpasure EM. Am J Med Sci 1919;158: 863-870Cui Z, Zhao MH. Nat Rev Nephrol. 2011 Dec 7:697-706,少见病：1-2/百万人口本研究所：累计诊断500余例国际上最大的临床资源库治疗依赖血浆置换：昂贵，但多为时已晚,抗GBM病仍然是我国内科医生的重大挑战,3,抗GBM病的发生情况,Cui Z, Zhao MH. Nat Rev Nephrol. 2011 Dec 7:697-706,抗GBM病研究现状,4,Hudson GB. Vanderbilt UniversityGBM molecular architecture of conformational epitopes,Pusey CD. HammersmithImperial College LondonPE in anti-GBM diseaseWKY rat modelGenetics of EAG models,Segelmark M & Wieslander JLund UniversityRecombinant antigensDetection of anti-GBM disease,Zhao MH & Cui ZPeking UniversityHuman anti-GBM diseaseLinear epitopesMolecular mimicry,Kitching AR. Monash University.MHC and T cell activationAnimal models,Lou YH. University of TexasT cell epitopeAnimal model,抗GBM病是典型的自身免疫病,靶抗原3(IV)NC1 （肺、肾）EpitopeEa和Eb-构象性,Saus J, et al. J Biol Chem 1988;15;263:13374-80Salant DJ. N Engl J Med 2010;363;4:381-391,5,6,抗GBM病的科学问题,病因表型差异,病因,遗传易感背景,自身免疫,T细胞,B细胞,3(IV)NC1,表型？,6,免疫耐受？,诱发因素？,7,抗GBM病的科学问题,病因表型差异肾受累轻重1/3合并ANCA少数合并MN,7,病因,遗传易感背景,自身免疫,T细胞,B细胞,3(IV)NC1,表型？,免疫耐受？,诱发因素？,8,23/M间断咯血 4 个月，加重1个月HGB: 71g/L; PO2 58mmHg; Scr 94.0 mol/l尿常规: protein (+), RBC 5-8/HPF血清抗GBM抗体 (+), ANCA (-)肾活检: IgG沿GBM线样沉积,肾小球轻微病变治疗：Pred 1 mg/kg/d x 8w, 无PE和CTX随访7年肾功能正常,Cui Z, et al. Kidney Int 2007;72:1403-8,8,肾受累轻患者介于正常人与重症患者之间？转换机制？,既往：健康人血清无抗GBM抗体发现天然抗GBM抗体：中国和瑞典：各10名献血员IgG成分-亲和层析“阴性选择”？如何发展成致病性抗体？,Cui Z, et al. Kidney Int 2006:69:894-9Cui Z, et al. Kidney Int 2010;78:590-7,Natural anti-GBM ab,9,抗GBM抗体如何转变成致病性？,天然抗GBM抗体,Anti-GBM (+)严重肾受累,Anti-GBM (+)正常肾功能,正常人,病人A,病人 C,Intra-moleculeEpitope spreading,3, 4,1、2、3、4和5,Subclass switching,IgG2、IgG4,IgG1、IgG2、IgG3和IgG4,治疗个体化T细胞调控,3 Ea、 Eb,3内其他位点,10,Anti-GBM (+)轻度肾受累,病人B,Cui Z, et al. Kidney Int 2006;69:894-9.Yang R, et al. J Am Soc Nephrol 2007;18(4):1338-43.Cui Z, et al. Kidney Int 2007;72(11):1403-8.Zhao J 8(1):51-8.,Inter-moleculeEpitope spreading,NATURE REVIEWS | NEPHROLOGY,Cui Z, Zhao MH. Nat Rev Nephrol. 2011 Dec;7:697-706.,抗GBM病的科学问题,病因表型差异肾受累轻重1/3合并ANCA少数合并MN,12,病因,遗传易感背景,自身免疫,T细胞,B细胞,3(IV)NC1,表型？,免疫耐受？,诱发因素？,13,抗GBM病合并MN,个例报道MN GBM damage：释放3 抗GBM 病抗GBM病足细胞损伤：表达M-PLA2R MN,13,8 patients with MN and anti-GBM diseaseSequential or simultaneousBetter prognosisAnti-3 (+): narrow antigen spectrumAnti-PLA2R (-),Jia XY, et al. Kidney Int2014 Apr;85(4):945-52,抗GBM病的科学问题,病因易感性：HLA？诱发因素病因表型差异,15,病因,遗传易感背景,自身免疫,T细胞,B细胞,3(IV)NC1,表型？,免疫耐受？,诱发因素？,16,抗GBM病的免疫学发病机制,Linear toConformational,涉及感染、抗原递呈、抗原决定簇扩展、分子模拟,17,Background ( HLA ),HLA geneLocation: CHR 6p21.3Classical HLA gene MHC class II molecular: Distribution : DCs、B cells、MStructure: hetero-dimerrecognized by CD4+ T cell Ag processed 、presentation MHC & disease: MS、RA、IDDM、 SLE et al.,18,(Rees, Kid Int, 1999),Dominantly protective alleles DR1 and DR7,No gene dosage effect,MHC II dominant protection,HLA-DRB1*01:01 generates 3136-146 specific regulatory T cells.HLA-DRB1*15:01 generates 3136-146 specific effector T cell precursors.In HLA-DRB1*15:01x01:01 mice, 3136-146 specific effector T cell precursors are dominantly suppressed by 3136-146 specific regulatory T cells,Rees et al, Kidney Int 1999 Ooi et al, J Am Soc Nephrol 2013,DRB1*1501 allele：p=1.597107 DRB1*0404 allele：p=0.037 Patients with DRB1*1501 or *0404 had more crescent formation. (p=0.021).,Yang R. et al. Clin Immunol 2009;133:245-250,19,Association of HLA alleles (4 digits, P3.55E-4),20,Determine the significantvariation marker of genotypeCase: 138 vs. Control: 599,rs41541412: the only significant SNP, belongs to DQA1*0502 nonsense mutation, change the 82th AA of DQ polypeptide.,Association of a novel HLA SNP(P3:Confirmed linkage. LOD-2: No linkage. LOD=0: the possibility is equal,Linkage analysis among the significant alleles,Unpublished data,抗GBM病的科学问题,病因易感性诱发因素：环境？病因表型差异,23,病因,遗传易感背景,自身免疫,T细胞,B细胞,3(IV)NC1,表型？,免疫耐受？,诱发因素？,24,抗GBM病的科学问题,病因易感性诱发因素病因：感染？表型差异,24,病因,遗传易感背景,自身免疫,T细胞,B细胞,3(IV)NC1,表型？,免疫耐受？,诱发因素？,25,假说：微生物可能是抗GBM病的病因之一,1919: Goodpasture首先报道1例18岁男性病人，咯血、急性肾衰竭流感？60%的患者发病前有前驱感染症状病原微生物-分子模拟?,Goodpasure EM. Am J Med Sci 1919;158: 863-870,25,分子模拟,B细胞表位T细胞表位,26,B细胞的线性抗原决定簇,合成24条重叠肽段：覆盖3(IV)NC1的234aa起始的线性抗原决定簇：P14（aa129-150）,Initiation epitope?,Risk epitope?,Jia XY, et al. Clin J Am Soc Nephrol 2012 Jun;7(6):926-33,P14(22mer)诱发WKY大鼠抗GBM肾炎,P14（aa129-150）分子内抗原决定簇扩展诱发自身免疫性T细胞增殖T/B细胞共同抗原决定簇,27,Unpublished data,B细胞的关键抗原决定簇与核心氨基酸基序,P14氨基酸序列:P14: TDIPPCPHGWISLWKGFSFIMFP14a:TDIPPCPHGWISLP14b: CPHGWISLWKGFSP14c: ISLWKGFSFIMFT,28,P14c逐个氨基酸突变B细胞识别的关键氨基酸基序GFxF,Unpublished data,29,Critical motif on P14 for pathogenicity,P14-1 ADIPPCPHGWISLWKGFSFIMFP14-2 TAIPPCPHGWISLWKGFSFIMFP14-3 TDAPPCPHGWISLWKGFSFIMFP14-4 TDIAPCPHGWISLWKGFSFIMFP14-5 TDIPACPHGWISLWKGFSFIMFP14-6 TDIPPAPHGWISLWKGFSFIMFP14-7 TDIPPCAHGWISLWKGFSFIMFP14-8 TDIPPCPAGWISLWKGFSFIMFP14-9 TDIPPCPHAWISLWKGFSFIMFP14-10 TDIPPCPHGAISLWKGFSFIMFP14-11 TDIPPCPHGWASLWKGFSFIMFP14-12 TDIPPCPHGWIALWKGFSFIMFP14-13 TDIPPCPHGWISAWKGFSFIMFP14-14 TDIPPCPHGWISLAKGFSFIMFP14-15 TDIPPCPHGWISLWAGFSFIMFP14-16 TDIPPCPHGWISLWKAFSFIMFP14-17 TDIPPCPHGWISLWKGASFIMFP14-18 TDIPPCPHGWISLWKGFAFIMFP14-19 TDIPPCPHGWISLWKGFSAIMFP14-20 TDIPPCPHGWISLWKGFSFAMFP14-21 TDIPPCPHGWISLWKGFSFIAFP14-22 TDIPPCPHGWISLWKGFSFIMA,Unpublished data,Tryptophan138, Isoleucine139, Leucine141, and Tryptophan142,P14129-150: TDIPPCPHGWISLWKGFSFIMF,抗GBM病-病因研究,针对致病微生物的研究细菌、病毒等培养（尚无来源）合成抗原分子利用生物信息学预测可能的T/B细胞抗原决定簇确定抗GBM病患者是否感染血清抗致病微生物蛋白抗体动物实验验证其致病性,30,8 patients with MN and anti-GBM diseaseSequential or simultaneousBetter prognosisAnti