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81.
Luo M Cohen CR Narayansingh MJ Pan S McKinnon L Brunham RC Plummer FA 《Tissue antigens》2004,63(6):609-611
We report a novel DQA1 allele (DQA1*0403N) identified during sequence-based HLA-DQA1 typing of a Kenyan population. The new allele is identical to DQA1*0401 at exon 2 except for a single-nucleotide substitution at codon 53, changing it from lysine to a stop codon (CAA-->TAA). The substitution at codon 53 was confirmed by sequencing two separate polymerase chain reaction products and by sequencing multiple clones obtained following TOPO-TA cloning. The resulting stop codon at position of codon 53 in exon 2 is predicted to produce a non-functional DQA1 alpha-chain. The new allele has been named by the WHO nomenclature committee as DQA1*0403N. This is the first report of a null allele detected in the DQA1 gene. 相似文献
82.
Identification of a new HLA-B*56 variant, B*5614 总被引:6,自引:0,他引:6
In this report, the novel allele B*5614 is presented. The allele was identified in a Chinese individual by sequence-based typing. HLA-B*5614 differs from B*5608 by a single nucleotide at position 277G-->C in exon 2. This results in an amino acid change from Gly to Arg at codon 93. 相似文献
83.
Takeshi Tana Nobuhiro Kamikawaji Christopher J. Savoie Tohru Sudo Yurika Kinoshita T. Sasazuki 《Journal of human genetics》1998,43(1):14-21
Susceptibility to a series of autoimmune diseases is strongly associated with particular HLA class II alleles. Identification
of T cell clones and antigenic epitopes bound by HLA class II molecules involved in autoimmune diseases is critical to understanding
the etiology of these HLA class II-associated diseases. However, establishment of T cell clones in autoimmune diseases is
difficult because the antigenic peptides are unknown. Peptide library methods which include all possible peptide sequences
offer a potentially powerful tool for the detection of cross-reactive antigenic peptides recognized by T cells. Here, we reduced
the number of peptides per mixture by utilizing the known binding motifs of peptides for the HLA-DRB1*0405 molecule and evaluated
the effectiveness of this library design. Each library mixture evoked a strong proliferative response in the unprimed peripheral
blood lymphocytes (PBL) from HLA-DRB1*0405-positive donors but little or no response in the PBL from HLA-DRB1*0405-negative donors. The library also detected antigenic peptides that activated three antigen-specific T cell lines restricted
by HLA-DRB1*0405, with different specificities. The motif-based approach thus presents a powerful method for monitoring T
cells in large, heterogeneous T cell populations and is useful for the identification of the mimic peptide epitopes of T cell
lines and clones.
Received: October 3, 1997 / Accepted: October 23, 1997 相似文献
84.
森林脑炎病毒prM-E蛋白在昆虫细胞中的表达及免疫活性测定 总被引:1,自引:1,他引:1
目的为了表达森林脑炎病毒prME蛋白,为森林脑炎快速诊断试剂的研制奠定基础。方法经过RTPCR扩增、重组转移载体构建、细菌内转座和昆虫细胞转染,以杆状病毒昆虫细胞表达系统成功地表达了森林脑炎病毒MDJ01株prME蛋白。结果从感染细胞上清中电镜观察到重组蛋白形成的球型颗粒,说明重组病毒感染细胞后产生病毒样表达颗粒(viruslikeparticlesVLPs),并且分泌至细胞外。免疫印迹试验和间接免疫荧光试验表明,表达的重组蛋白能够与抗森林脑炎病毒抗体特异结合,具有良好的抗原性。ELISA和间接免疫荧光染色证实,重组prME蛋白可以作为抗原用于检测患者血清特异性抗体。结论在昆虫细胞中表达的prME具有良好的抗原性,本研究为森林脑炎快速特异诊断试剂研制奠定了基础。 相似文献
85.
Mayor NP Cox ST McWhinnie AJ Argüello JR Shaw BE Little AM Madrigal JA Marsh SG 《Tissue antigens》2005,65(1):107-109
We report here the full-length sequence of a novel HLA-A*0301 allele, A*03010103, which differs from A*03010101 by a single nucleotide substitution (G>T) at position 492 within intron 2. The variant was originally identified by Reference Strand-mediated Conformational Analysis (RSCA) and was confirmed by cloning and sequencing. The difference in RSCA mobility between A*03010101 and A*03010103 demonstrates the sensitivity of RSCA to detect single nucleotide polymorphisms. 相似文献
86.
Hurley CK Steiner N Gans CP Kosman C Mitton W Koester R Jones P Edson S Rizzuto G Hartzman RJ Ng J Rodriguez-Marino SG 《Tissue antigens》2001,57(5):474-477
Twelve new B*15 alleles are described. All of the known B*15 alleles are divided into subgroups based on serologic assignments and/or nucleotide sequence polymorphisms. These groups might be used as a reference for DNA-based testing at an intermediate (i.e. "serologic") level of resolution. 相似文献
87.
5-HT 102T/C多态性与Tourette综合征的病例对照及核心家系关联分析 总被引:3,自引:0,他引:3
目的 研究5-羟色胺受体102T/C多态性是否与Tourette综合征(TS)相关联,方法对157个核心家系样本采用病例-对照关联分析,传递不平衡检验方法,聚合酶链反应及RFLP等技术,根据TS与强迫症(obsessive compulsive disorder,OCD)的同病现象,将TS划分亚组进行与5-羟色胺受体102T/C多态性的关联分析。结果 合并OCD的TS与该位点的基因型102C/C(X2=8.38,P=0.004)及等位基因102C/(X2=4.84,P=0.028)存在关联,进一步采用传递不平衡分析,发现合并(美国精神疾病诊断和统计手册IV》论断标准的OCD的TS与该位点存在关联或连锁不平衡(X2=5.12,,P=0.02),而在TS总体样本及单纯TS样本中未发现与该位点的关联,结论 5-羟色胺受体102T/C多态性与中国人群合并OCD的TS存在关联,合并OCD的TS可能是TS中相对独立的一个亚型。 相似文献
88.
In this report, we describe the identification of a human leucocyte antigen-A*11 (HLA-A*11) nucleotide sequence variant, a new HLA-A*1120 by using sequence-based typing (SBT). The new allele was detected during routine HLA typing by high-resolution SBT. Allele A*1120 showed one nucleotide difference with A*110101 at codon 152 (GCG-->GAG) resulting in an amino acid change from alanine to glutamate. Residue 152 is located on alpha(2)-helix of HLA class I molecule and involved in peptide binding by constructing E pocket of peptide-binding groove, implying that the change of the residue 152 would affect the binding affinity of peptides to A*1120 allele. 相似文献
89.
目的:优化诱导条件大批量表达生物素化酶BirA底物肽(BSP)与HLA-A*0203重链胞外域的融合蛋白(HLA—A*0203、BSP),并制备负载HLA-A*0203限制性EB病毒抗原肽EBNA3 596-604的四聚体(HIA—A}0203/SVR)。方法:以HLA—A*0203-BSP原核表达载体转化E.coli BL21(DE3)菌株,优化诱导条件进行大批量重组蛋白的表达。通过稀释法复性可溶性HLA-A*0203/SVR单体,然后以BirA对其进行生物素化,并以阴离子交换树脂纯化。将纯化的HLA-A*0203/SVR单体与荧光素标记的链亲和素按4:1的比例混合形成四聚体,通过对特异性CTL进行染色验证其结合活性。结果:当IPTG的浓度为0.4mmol/L,于37℃诱导过夜后,融合蛋白的表达最多。该重组蛋白相对分子质量(Mr)为34003,与HLA—A*0203-BSP的理论Mr相一致。该重组蛋白以包涵体形式存在于沉淀部分,约占菌体总蛋白的30%。负载抗原肽的可溶性HLA-A*0203/SVR单体是在同时存在HLA-A*0203,BSP、β2微球蛋白及HLA-A*0203限制性抗原肽SVR的情况下通过稀释法复性而获得。该单体生物素化并纯化后与荧光素标记的链亲和素按4:1的比例混合后即形成四聚体。流式细胞术(FCM)分析证实,该四聚体具有与HLA—A2^+供者特异性CTL结合的活性。结论:HLA—A*0203-BSP融合蛋白在优化条件下获得高效表达。以此蛋白制备的HLA-A*0203/SVR四聚体具有与HLA-A2^+供者特异性CTL结合的活性,为研究HLA—A*0203个体EB病毒特异性CTL的免疫应答打下了基础。 相似文献
90.
Three novel DRB3* alleles were identified using CANTYPE reverse hybridization assay. The initial unusual hybridization patterns of DRB3-specific polymerase chain reaction (PCR)-amplified DNA from each subject were confirmed by cloning and sequencing analysis. DRB3*0106 allele is identical to DRB3*0101 except for a single nucleotide substitution (CTG-->GTG) changing codon 38 from Leu to Val. This polymorphism is commonly found in DRB3*03 alleles. Compared with DRB3*0202, DRB3*02022 contains a single silent nucleotide substitution (AAT-->AAC, both encoding for Asn) at codon 77. This polymorphism is also present in DRB3*0204 allele. The new DRB3*0107 allele has a sequence unique to DRB3 alleles. From codon 5 to codon 36 the sequence is identical to that of DRB3*0101 allele. From codon 37 to codon 87 the sequence of DRB1*0107 allele is identical to that of DRB3*0202. This sequence would thus explain the CANTYPE(R) DRB3-specific unusual pattern of reactions. The new DRB3*0107 could have arisen from a gene conversion between DRB3*0101 and DRB3*0202 alleles, but the DRB3*0106 and the DRB3*02022 may have been generated by a point mutation event. The DRB3*0107 allele was identified in a Caucasoid individual. The ethnic origin of the subjects carrying the other two alleles are unknown. The three alleles presented here were only identified once, in a total population of 49,000. 相似文献