摘要:

Abstract:HLA B‐locus typing by group‐specific PCR and hybridization with SSOP was performed in 81 10th IHWS B cell lines and 334 selected subjects of our local panel, from four ethnic groups. Most of the B‐locus serological specificities were well defined. However, some antigens like B41, B58, B56, the splits of B14, and some subtypes of B5, were not accurately assigned by serology. In the panel studied, we found 17 hybridization patterns that corresponded to probable new alleles. New patterns occurred in the four ethnic groups examined. Multiple subtypes of B35, B5, B15, B41, B44, B57, B58, B70, B14, B40, B22 were found in subjects of the same ethnic group. In view of the poor serological definition of some alleles, and the occurrence of multiple subtypes in the same ethnic population, it appears that high resolution B‐locus typing may be an important addition for detection of potentially relevant HLA incompatibilities in transplantation. It should also be valuable for population studies and for the investigation of HLA associations with d

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02435.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:The aim of this study was to investigate the contribution of the different B27 subtypes to ankylosing spondylitis (AS) susceptibility. The polymerase chain reaction (PCR) in combination with the sequence‐specific oligonucloetide probes (SSOs) was used to analyse the polymorphism in exon 2 and 3 of HLA‐B27 in two Asian groups with different genetic HLA structures: Indian (I) and Thai (T) populations. The same number of AS patients (45) and healthy B27 positive donors (n=17) from both populations were analysed in order to ascertain the B27 subtypes. Three different findings can be concluded from this study: 1) B*2707 has been found to be associated with AS in both populations. This association has not been previously reported in either ethnic group. 2) B*2704 is strongly associated with AS in the Thai patients (91% in AS vs. 47% in C; RR=11.5; EF=0.83). In contrast, B*2704 was found with similar frequency in Asian Indians AS patients and controls (41% in AS vs. 41% in G). 3) B*2706 was found overrepresented in control populations and absent in AS patients (0% in AS vs. 47% in C; pc<10‐6) showing the maximum value of protective fraction (PF=1). The B*2706 negative association with AS has not been previously described in other ethnic groups and could indicate a protective effect of this subtype on AS susceptibility. The B*2706 allele has two changes relative to B*2704 at residue 114 (His to Asp) and 116 (Asp to Tyr) in the pockets D/E. The importance that these differences can play in the pathogenesis of AS are disc

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02436.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:Daudi, a lymphoblastoid B cell line derived from an African Burkitt lymphoma does not express HLA‐A,B,C antigens at the cell surface. Although HLA‐A,B,C heavy chains are made normally they do not assemble into functional molecules because β2‐microglobulin is absent. Previous serological analysis of somatic cell hybrids indicated that the HLA haplotypes of Daudi encoded HLA‐A1, A10(A26), B17, and B16(38) antigens. Here we describe the application of molecular methods: ARMS‐PCR, cDNA cloning and sequencing, immunoprecipitation and gel electrophoresis, to define the class I genotype of the Daudi cell line which is HLA‐A*0102, A*6601, B*5801, B*5802, Cw*0302 and Cw*0602. With the exception of the B38 antigen, which is not a product of the alleles defined, the genotype is consistent with the serological description. Two previously undiscovered alleles emerged from this analysis: A*0102 and B*5802. The A*0102 allele differs from A*0101 by 5 nucleotide substitutions within exon 2 where it has a motif shared with A*30 alleles; the B*5802 allele differs from B*5801 by 3 substitutions in exon 3 where it has a motif shared with B*14 alleles. Subtyping HLA‐A 1 alleles showed A*0102 was well represented amongst individuals typed serologically as Al in an African population but was absent from caucasoids. B*5802 has been found in a second individual. Thus the novel A and B alleles are not specific to the Daudi tumor. Overall, this analysis of a single East African cell illustrates the power of molecular methods to define new class I HLA alleles in non‐cauca

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02437.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:In several systems it has been shown, that non‐responsiveness to an antigen in mice of a particular haplotype is due to the lack of binding of an immunogenic peptide to class II molecules. Such studies have been done using detergent solubilized, affinity purified class II molecules. It has been reported, that the presence of certain phospholipids around class II molecules dramatically alters the extent of peptide binding to these molecules. It thus appears that the milieu in which the class II molecules are inserted influences to a considerable extent the level of peptide binding. Hence it is likely that the kinetics of binding of immunogenic peptides to class II on the cell surface, may be different from that of molecules inserted in detergent micelles. We therefore decided to test this by studying the binding of radiolabeled peptides to class II molecules on cell membranes. We report here a rapid and sensitive assay for peptide binding to murine class II molecules on cell membranes. Further, we have used this assay to study the nature of the interaction of immunogenic peptides and class II molecules on cell membranes of mice who are responders and non‐responders to Hepatitis B surface Antigen (HBsAg). Interestingly, we find that immunogenic peptides bind in good correlation with their MHC restriction. We also observe that the HBsAg derived peptide which is unable to elicit a T cell response in the non‐responder B10.M strain actually binds to the class II of the non‐responder but fails to make a stable class II‐peptide complex. We thus conclude that defective antigen presentation may be one of the possible explanations, underlying the mechanism of non‐res

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02438.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:The association of multiple sclerosis (MS) with the HLA class II loci DR and DQ was investigated in populations of Asian Indian and Afro‐Caribbean ethnic origin, resident in the United Kingdom. The putative haplotype, DRB1*150l.DQA1*0102.DQB 1*0602, was weakly positively associated with MS in both races. The overall contribution to disease susceptibility of this marker was small. Over 80% of the MS patients in both racial groups did not possess this haplotype. The data suggest that other genetic and/or environmental factors may be more important in predisposing to MS in these two races. Our study also raises the possibility that genetically distinct forms of the disease may be expressed in white Caucasian and non‐Caucasian populati

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02439.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:Monomorphic and polymorphic anti‐HLA monoclonal antibodies (mAb) are valuable reagents for assessment of the structural and functional importance of different class I determinants. We have generated a new mAb, RG1, reacting with an epitope variably expressed on normal and leukemic hematopoietic cells of different lineages. Immunoprecipitation of the RG1 antigen disclosed a bimolecular complex characteristic of class I proteins. The RG1 epitope was expressed on an HLA‐A2 transfected cell line but not on cells transfected with HLA‐E, ‐F or ‐G molecules. MAb reactivity with reference B‐lymphoblastoid cell lines and HLA typing of RG1 reactive and unreactive cells demonstrated that the epitope was expressed in conjunction with defined HLA‐A molecules. Cells expressing HLA‐A2, ‐A24(9) and ‐A68(28) proteins were brightly stained with RG1 whereas mAb binding to HLA‐A1, ‐A11 and a split of A3 molecules was significantly lower. In contrast, the RG1 epitope was apparently not expressed on HLA‐A23(9), ‐A25(10), ‐A26(10), ‐A29(19), ‐A30(19), ‐A31(19), ‐A32(19), ‐A33(19) and some HLA‐A3 molecules. Based on class I α sequence data, these results suggest that the RG1 epitope is localized to a region of the α2 helix accessible to the T cell receptor for antigen on cytotoxic T lymphocytes. Lys in position 144 and His in position

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02440.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02441.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02442.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0001-2815    

DOI:10.1111/j.1399-0039.1995.tb02443.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY