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71.
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
72.
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
73.
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
74.
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
75.
S.?Mori N.?Muroi S.?Ono H.?K.?Takahashi M.?NishiboriEmail author 《Inflammation research》2004,53(4):164-169
Objective and Design: Carboxymethylcellulose (CMC) has been considered to be inert and is commonly used as an additive in medicines, foods and cosmetics. However, we experienced a patient who developed an anaphylactic reaction to CMC after an upper gastrointestinal examination using a barium meal containing CMC. Therefore, we examined the incidence of sensitization by CMC in healthy subjects, and categorized the high risk group prone to developing anaphylactic response to CMC.Methods: An ELISA for detecting CMC-specific IgE antibody was developed using serum from the patient as a positive control. In the ten subjects exhibiting high anti-CMC IgE among 387 normal populations, histamine release from isolated leukocytes was performed.Results: Five of ten subjects with a high IgE titer showed a significant CMC-induced histamine release from leukocyte preparations in vitro as observed in the patient, and were classified as high risk group. There was a correlation between sensitization by CMC and that by Japanese cedar pollen. The incidence of sensitization in females was 2.4 fold higher than that in males.Conclusions: The combination of ELISA and histamine release experiment made it possible to identify the high risk group for developing anaphylactic response. The administration of high dose CMC as a suspending agent in barium sulfate or injectable corticosteroids to this group should be avoided to prevent anaphylactic reactions in the clinic.Received 18 August 2003; returned for revision 29 September 2003; accepted by M. J. Parnham 10 December 2003 相似文献
76.
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
77.
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
78.
Takakuwa K Hataya I Arakawa M Kikuchi A Higashino M Yasuda M Kurabayashi T Tanaka K 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,42(4):233-239
PROBLEM: To clarify whether HLA-DP antigens are associated with patient population of unexplained recurrent abortion. METHOD OF STUDY: The frequency of HLA-DPB1 alleles in patients with unexplained recurrent abortion, and the compatibility of HLA-DPB1 alleles between patient couples, were studied using a polymerase chain reaction (PCR)-restricted fragment length polymorphism (RFLP) method. Thirty patients who had a history of unexplained primary recurrent abortion, and their husbands, were typed for HLA-DPB1 genotype. Two hundred and ninety-nine base pair fragments from the second exon of HLA-DPB1 genes were selectively amplified using the PCR-primers. After amplification, the DNAs were digested with restriction endonucleases, and subjected to electrophoresis in a 12% polyacrilamide gel to determine HLA-DPB1 genotype. RESULTS: The frequency of HLA-DPB1*0402 and DPB1*04 alleles in the patient group (n = 30) was significantly increased, as compared to that in the normal fertile women (n = 30). The frequency of HLA-DPB1*04 allele in the patient group was significantly increased, as compared to that in the general population (n = 112). No significant compatibility of HLA-DPB1 alleles could be observed between patient couples and normal fertile couples. CONCLUSION: These findings suggest a possible new class II association with patient population of unexplained recurrent abortion. 相似文献
79.
Abstract: Three novel HLA class H alleles (DRB1*1333, DRB1*O426, DRB5*0109) are described here. The 3 novel alleles were initially detected as previously unidentified SSO hybridization patterns using the CANTYPE reverse hybridization assay. Sequences were determined by cloning/sequencing. DRB1*1333 is identical to DRB1*1303 except for a single nucleotide substitution (ACC→AAC), changing codon 77 from Thr to Asn. This polymorphism is typical for DRB1*03 alleles. DRB1*0426 is identical to DRB1*0401 except for a single nucleotide substitution (GCC→ACC) at codon 58, changing the encoded Ala to Thr. DRB5*0109 is identical to DRB5*0101, except for a single nucleotide substitution (GAC→AAC), changing codon 70 from Asp to Asn. Both latter polymorphisms were so far undetected in DRB alleles. DRB1*1333 could have arisen from a gene conversion event, but DRB1*0426 and DRB5*0109 most likely were generated by point mutation events. For all 3 alleles, the sequence was confirmed by the original hybridization pattern (DRB1*1333) or by hybridization to a newly designed probe (DRB1*0426 and DRB5*0109). Ethnic backgrounds were Lebanese for DRB1*1333 and Caucasian for DRB1*0426 and DRB5*0109. 相似文献
80.
We have investigated the frequencies of HLA-A*02 alleles and their haplotypic associations with HLA-B and -DRB1 loci in 439 healthy unrelated Koreans, including 214 parents from 107 families. All of the 227 samples (51.7%) typed as A2 by serology were analyzed for A*02 alleles using polymerase chain reaction (PCR)-low ionic strength-single-strand conformation polymorphism (LIS-SSCP) method. A total of six different A*02 alleles were detected (A*02 allele frequency 29.6%): A*0201/9 (16.6%), *0203 (0.5%), *0206 (9.3%), *0207 (3.0%), and one each case of *0210 and *02 undetermined type. Two characteristic haplotypes showing the strongest linkage disequilibrium were A*0203-B38-DRB]*1502 and A*0207-B46-DRB1*0803. Besides these strong associations, significant two-locus associations (P<0.001) were observed for A*0201 with B61, DRB1*0901 and DRB1*1401, and for A*0206 with B48 and B61. HLA haplotypes carrying HLA-A2 showed a variable distribution of A*02 alleles, and all of the eight most common A2-B-DR haplotypes occurring at frequencies of > or =1% were variably associated with two different A*02 alleles. These results demonstrate that substantial heterogeneity is present in the distribution of HLA-A*02 alleles and related haplotypes in Koreans. 相似文献