免疫球蛋白基因组.pptx

ImmunoglobulinStructuresHeavy chain and light chain(and)Constant regionClass:IgA,IgD,IgE,IgG and IgMVariable region Antigen binding site第1页/共18页Generation of diversitiesAIDN-Regions第2页/共18页Part 1 Immunoglobulin germline gene repertoire study第3页/共18页IGHV gene repertoireHighly polymorphic226 reported genes and allelic variants104 was reported in error 12 putative new polymorphisms,3 have been sequencedConclusion:The existing IGHV gene repertoire is full of incorrectly reported sequences.第4页/共18页IGKV gene repertoire analysisCompilation of Database Compilation of Database 1863 rearranged IGKV sequences from the EMBL1863 rearranged IGKV sequences from the EMBL 66 germline genes from the IMGT66 germline genes from the IMGTAlignments using Smith-Waterman algorithm.Alignments using Smith-Waterman algorithm.Unreported IGKV allelesUnreported IGKV alleles IGKV alleles with low number of unmutated sequences were IGKV alleles with low number of unmutated sequences were collectedcollected Multiple alignmentMultiple alignment Shared mismatchesShared mismatches Sequencing from genomic DNASequencing from genomic DNA第5页/共18页Junction analysis of IGK genes435 low mutation sequences(3 IGKV mutations)were realigned to determine IGKJ genes using V-QUESTVJ gene useageN-Region第6页/共18页第7页/共18页Results5 reported genes may be the result of 5 reported genes may be the result of sequencing errorssequencing errorsIGKV1D-13*01 and IGKV1-37*01 may be IGKV1D-13*01 and IGKV1-37*01 may be functional in some individualsfunctional in some individualsUnreported polymorphisms:IGKV1-16*02 and Unreported polymorphisms:IGKV1-16*02 and IGKV2-30*02.IGKV2-30*02.The existing IGKV repertoire is relatively The existing IGKV repertoire is relatively complete and accuratecomplete and accurate第8页/共18页第9页/共18页ConclusionsNot only is there little diversity in the germline Not only is there little diversity in the germline genes of the kappa locus,but little junctional genes of the kappa locus,but little junctional diversity is generated during the process of gene diversity is generated during the process of gene rearrangement.rearrangement.The immunoglobulin gene repertoire can The immunoglobulin gene repertoire can therefore be characterised as having therefore be characterised as having extraordinary diversity in the heavy chain,and extraordinary diversity in the heavy chain,and limited diversity in the light chain.limited diversity in the light chain.第10页/共18页Part 2Sequencing immunoglobulin genes from allergic and parasitised individuals第11页/共18页IgE and AllergyNatural function of IgE Parasite infectionsIgE and Allergic diseaseAntigen selection in IgEThe relationship between IgE and IgG4第12页/共18页Understanding IgE mutations in PNGPNG IgE vs PNG IgGOther Factors Exposure to pathogensExposure to pathogens AgeAge第13页/共18页Two QuestionsIs there a higher level of mutation in antibodies of PNG villagers,compared to Australia urban individuals?Are higher numbers of mutations seen in older individuals?第14页/共18页第15页/共18页Sample NameIgEIgGNo.of IgAverage Mutation No.No.of IgAverage Mutation No.Australia1812.85217.6A000001019.5A0021102418.8A006910.61815.1A007815.600PNG2017.76619.8P002(Old)423620.3P008(Old)1417.11423.1P011(young)211.54618.8第16页/共18页AcknowledgementsAndrew Collins William SewellKatherine JacksonViveka SinghEllie PrattBruno GaetaJeanette VillanuevaJames LazenbyChristine WhittallAngela Higgins第17页/共18页Thank you!第18页/共18页