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ABSTRACT: Two new TCRVβ coding region polymorphisms were identified: Vβ6.9a/b and Vβ21.4a/b. In both cases, a single nucleotide difference gives rise to an amino acid exchange. Genomic typing by the PCR/sequence-specific oligonucleotide probing technique was performed to study a possible contribution of these two new polymorphisms in susceptibility to autoimmune diseases. However, there was no association with insulin-dependent diabetes mellitus, rheumatoid arthritis, juvenile rheumatoid arthritis, multiple sclerosis, myasthenia gravis or coeliac disease. On the other hand, significant differences were found between Caucasoid and Oriental populations in frequencies of the Vβ6.9 and Vβ21.4 alleles.
Scandinavian Journal of Immunology 06/2006; 36(2):285 - 290. · 2.23 Impact Factor
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ABSTRACT: EBV-transformed B cells from a multiparous woman with anti-HLA antibodies were hybridized with CB-F7 heteromyeloma cells. The resulting hybridoma produced the cytotoxic human IgM(kappa) mAb 5643. Testing of the hybridoma supernatant against HLA homozygous cell lines demonstrated positive reactions (titer range 128-512) only with three cell lines that carried the DR (alpha, beta 1*0801) subtype of DR8. There was no reaction with cells expressing other variants of DR8; i.e., carrying the DR beta 1*0802, 0803, or 0804 chains. The only difference between the DR beta 1*0801 and DR beta 1*0802/0804 chains and between the DR beta 1*0801 and 0803 chains is a single aa substitution, a Ser-->Asp substitution at residue 57 and a Phe-->Ile substitution at residue 67, respectively. Residues 57 and 67 are both situated on the alpha-helix of the DR beta chain. The distance between residues 57 and 67 is two full turns of the alpha-helix; i.e., about 1 nm. It is possible that both 57 Ser and 67 Phe are directly involved in the epitope recognition by mAb 5643.
Human Immunology 08/1995; 43(3):200-6. · 2.84 Impact Factor
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ABSTRACT: The human cytotoxic hybridoma antibody 4166 (IgM kappa) was generated by fusing an in vitro EBV-transformed B-LCL from a multiparous woman with the mouse-human heteromyeloma fusion partner CB-F7. In microcytotoxicity and IIF tests with B-LCLs as target cells, the mAb 4166 was specific for DQ3 (= DQ7 + 8 + 9). However, when used for DQ typing of class-II-positive PBMCs, 4166 could be rendered functionally specific for DQ7 + 8 and did not react with DQ9+ PBMCs. Binding of mAb 4166 to DQ8-positive cells was efficiently blocked by several allotype-specific mAbs recognizing DQ8. Other HLA class-II-specific mAbs were unable to inhibit. With the use of mAb 4166, it is possible to discriminate DQ7 + 8 from DQ9 in serologic DQ typing.
Human Immunology 05/1995; 42(4):281-8. · 2.84 Impact Factor
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ABSTRACT: CD is precipitated in susceptible individuals by ingestion of wheat gluten. The disease is strongly associated to the HLA-DQ(alpha 1*0501, beta 1*0201) (DQ2) heterodimer, where both the DQ alpha and DQ beta chains are required for susceptibility. We have recently shown that gluten-specific CD4+ T cells from the small intestinal mucosa of CD patients are predominantly restricted by the CD-associated HLA-DQ(alpha 1*0501, beta 1*0201) heterodimer. Here we report studies on the influence of aa substitutions in the DQ beta 1*0201 chain on DQ2-restricted T-cell recognition of gluten antigens. A B-LCL expressing the DQ(alpha 1*501, beta 1*0301) heterodimer was transfected with the DQB1*0201 gene, or with DQB1*0201 genes altered by site-directed mutagenesis. Surface expression of the wild-type or mutated DQ(alpha 1*0501, beta 1*0201) heterodimers was observed in the transfectants. Seven DQ2-restricted, gluten-specific TCCs were then investigated with respect to their ability to recognize antigen presented by the transfectants. All TCCs were sensitive to one or more of the aa substitutions induced but showed different response patterns. The results demonstrate that single aa substitutions of the DQ beta 1*0201 chain at positions in the peptide-binding cleft of DQ(alpha 1*0501, beta 1*0201) may affect binding of gluten-derived peptides and/or interfere with T-cell recognition. Because all seven TCCs studied were differently affected, they probably differ with respect to glutenpeptide and/or DQ(alpha 1*0501, beta 1*0201) restriction fine specificity.
Human Immunology 03/1995; 42(2):145-53. · 2.84 Impact Factor
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ABSTRACT: We have characterized and described in detail 2 CD4+ T-lymphocyte clones (TLC) from a colonic cancer patient. These TLC specifically recognize a K-ras-derived peptide carrying the 13Asp mutation commonly found in adenocarcinomas of the colon. The TLC were independently derived, as they carried 2 different T-cell receptors. The TLC recognized partly overlapping epitopes within the 13Asp peptide, presented by HLA-DQ7 molecules, suggesting that this molecule might confer some protective immunity against the mutation. On the basis of analysis of 251 colonic carcinomas, the presence of HLA-DQ7 did not seem to protect against the establishment of carcinomas carrying the 13Asp mutation, since the frequency of the DQ7 haplotype was not decreased among patients having this mutation. A modifying effect of DQ7 on the development of carcinomas with a 13Asp mutation was, however, observed, resulting in fewer tumours reaching advanced Dukes stages when DQ7 was present.
International Journal of Cancer 09/1994; 58(4):506-11. · 5.44 Impact Factor
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Tissue Antigens 05/1994; 43(4):266-70. · 2.59 Impact Factor
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ABSTRACT: Staphylococcal exotoxins (SE) are potent mitogens for human and murine T cells. Extensive studies in mice have demonstrated strict correlations between T-cell responses to individual SE and TCR V beta expression. Studies examining the TCR V beta expression of SE-activated human peripheral blood T cells also suggest close correlations, whereas the data reported using human T-cell clones (TCC) are conflicting. We have determined the cDNA TCRB sequences of 52 different human TCC, expressing 35 different T-cell receptor V beta (TCRBV)-encoded sequences. The TCC were tested in proliferative assays using nine different SE. Most of these TCC express V beta s which have not been tested previously in studies examining interaction between TCC and SE. The SE stimulated a variable fraction (1/48-31/52) of the TCC. The ability of a given SE to stimulate TCC in many cases correlated with V beta expression, but several exceptions were found. With one possible exception, comparisons between deduced amino-acid sequences within the 'fourth hypervariable region' of the TCR beta chain and SE responsiveness did not reveal potential SE binding motifs. We conclude that the reactivity of T cells towards SE is governed mainly by their TCR V beta expression. However, the authors' results also suggest that the interaction between SE and human T cells may involve elements unidentified as yet which are in addition to the beta chain of the TCR.
Scandinavian Journal of Immunology 05/1994; 39(4):387-94. · 2.23 Impact Factor
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ABSTRACT: Whether T cells specific for a particular peptide/HLA-DQ complex are restricted with respect to TCR usage has not been fully established. TCR usage of T cells specific for a peptide presented by a given HLA-DQ molecule has not been studied before. We therefore sequenced the TCR genes of five different TCCs derived from the same donor, which were specific for a p21 ras-derived synthetic peptide presented by the HLA-DQ(alpha 1*0102,beta*0602) (DQ6) molecule. We found that these T cells which recognized the same peptide/HLA-DQ complex used highly diverse TCRs. However, dose-response experiments using various truncations of the p21 ras-derived peptide revealed that the peptide fine specificities of the five TCCs were not completely identical. This may explain the heterogeneity in TCR usage.
Human Immunology 02/1994; 39(1):61-8. · 2.84 Impact Factor
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ABSTRACT: Mutations in ras genes which result in transforming gene products carrying amino acid substitutions in position 12, 13 or 61 are common in human cancer. Peptides encompassing these mutations in ras are shown to be immunogenic in both mice and humans. The potential usefulness of such peptides in cancer therapy, depends on their ability to bind to HLA molecules. We therefore stimulated T cells from healthy donors with mutated ras-derived peptides. By repeated in vitro stimulation of peripheral blood mononuclear cells, several T cells clones could be generated which recognized a p21 ras derived peptide carrying a position 12 Gly-->Arg substitution. This peptide (1-25,12 Arg) could be specifically recognized by T cells restricted by either HLA-DQ7 or -DP3. Previously, we showed that this peptide is also recognized by a T cell clone restricted by HLA-DR2. The core region of the peptide was determined to span positions 9-16 for all three HLA restriction elements, and accordingly contains the mutational hot spots in position 12 and 13. The observation that the mutant 1-25,12 Arg ras-derived peptide may contain a promiscuous epitope encompassing the Gly-->Arg mutation in position 12 indicates that lack of peptide presentation by given HLA molecules may not be a major constraint in responsiveness against ras mutations.
European Journal of Immunology 10/1993; 23(10):2687-91. · 5.10 Impact Factor
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ABSTRACT: Celiac disease (CD) is most probably an immunological disease, precipitated in susceptible individuals by ingestion of wheat gliadin and related proteins from other cereals. The disease shows a strong human HLA association predominantly to the cis or trans encoded HLA-DQ(alpha 1*0501,beta 1*0201) (DQ2) heterodimer. T cell recognition of gliadin presented by this DQ heterodimer may thus be of immunopathogenic importance in CD. We therefore challenged small intestinal biopsies from adult CD patients on a gluten-free diet in vitro with gluten (containing both gliadin and other wheat proteins), and isolated activated CD25+ T cells. Polyclonal T cell lines and a panel of T cell clones recognizing gluten were established. They recognized the gliadin moiety of gluten, but not proteins from other cereals. Inhibition studies with anti-HLA antibodies demonstrated predominant antigen presentation by HLA-DQ molecules. The main antigen-presenting molecule was established to be the CD-associated DQ(alpha 1*0501, beta 1*0201) heterodimer. The gluten-reactive T cell clones were CD4+, CD8-, and carried diverse combinations of T cell receptor (TCR) V alpha and V beta chains. The findings suggest preferential mucosal presentation of gluten-derived peptides by HLA-DQ(alpha 1*0501, beta 1*0201) in CD, which may explain the HLA association.
Journal of Experimental Medicine 08/1993; 178(1):187-96. · 13.85 Impact Factor
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Transplantation Proceedings 03/1993; 25(1 Pt 1):72. · 1.00 Impact Factor
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Transplantation Proceedings 03/1993; 25(1 Pt 1):70-1. · 1.00 Impact Factor
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Immunogenetics 02/1993; 38(6):444-5. · 2.93 Impact Factor
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ABSTRACT: We studied whether antigen-specific T cells being restricted by the very similar HLA-Dw4 and/or -Dw14.1 molecules might demonstrate homogeneities in parts of their TCR. TCCs were generated from three individuals who were all HLA-Dw4/Dw14.1 heterozygous. Thirty-five TCCs specific for PPD or TT and restricted by HLA-Dw4 and/or -Dw14.1 were selected for TCR beta gene sequencing. We found that 19 different V beta genes from 13 V beta families were expressed by these TCCs. Thus, it seems that many different TCRV beta genes may be used by TCCs restricted by these HLA molecules. For PPD-specific TCCs, a possible biased usage of V beta 8, as well as possible preferential usage of a CDR3 motif, were found.
Human Immunology 12/1992; 35(3):149-56. · 2.84 Impact Factor
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ABSTRACT: Two new TCRV beta coding region polymorphisms were identified: V beta 6.9a/b and V beta 21.4a/b. In both cases, a single nucleotide difference gives rise to an amino acid exchange. Genomic typing by the PCR/sequence-specific oligonucleotide probing technique was performed to study a possible contribution of these two new polymorphisms in susceptibility to autoimmune diseases. However, there was no association with insulin-dependent diabetes mellitus, rheumatoid arthritis, juvenile rheumatoid arthritis, multiple sclerosis, myasthenia gravis or coeliac disease. On the other hand, significant differences were found between Caucasoid and Oriental populations in frequencies of the V beta 6.9 and V beta 21.4 alleles.
Scandinavian Journal of Immunology 09/1992; 36(2):285-90. · 2.23 Impact Factor
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ABSTRACT: To investigate whether T cells recognizing the same HLA molecule may demonstrate homology in parts of their TCR, five different HLA-DQw8-specific T lymphocyte clones (TLC) were studied. The TCR alpha and -beta genes of four alloreactive, HLA-DQw8-specific and one antigen-specific TLC were sequenced. All TLC used different V alpha and V beta genes. However, four of the TLC shared a certain CDR1 beta motif and all five used either J beta 2.3 or -2.5. In addition, two used the same J alpha. The results indicate a possible preferential usage of certain TCR structures by T cells specific for DQw8.
International Immunology 09/1992; 4(8):931-4. · 3.41 Impact Factor
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Tissue Antigens 06/1992; 39(5):280. · 2.59 Impact Factor
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ABSTRACT: T-cell receptor beta chain mRNA from 4 human T-lymphocyte clones was reverse transcribed, amplified by PCR, cloned in M13 and sequenced. Four hitherto undescribed variable genes were found. One of them (V beta-IW22) showed the highest homology (74.5%) to V beta 1. Two others (V beta-IW6 and V beta-IW10) belonged to the recently described V beta 21 family. The last gene (V beta-VW114) belonged to the V beta 9 family. However, the latter gene a is pseudogene because of an in-frame stop codon.
Tissue Antigens 10/1991; 38(3):99-103. · 2.59 Impact Factor
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ABSTRACT: Insulin-dependent diabetes mellitus (IDDM) susceptibility is associated with the DR4-DQw4 haplotype in Japanese and the DR4-DQw8/-Drw8-DQw4 genotype (among others) in whites. We investigated whether these Japanese and white individuals encode the same or a similar DQ alpha beta heterodimer, which may be an IDDM-susceptibility molecule in both populations. First, we carried out genomic DQA1 and DQB1 typing with sequence-specific oligonucleotide probes. The results revealed that Japanese DR4-DQw4 and white DR4-DQw8/DRw8-DQw4 IDDM patients carried the DQA1*0301 allele and the DQB1*0401 or DQB1*0402 allele, either in the cis (Japanese DR4-DQw4 individuals) or trans (white DR4-DQw8/DRw8-DQw4 individuals) position. Because the DQB1*0401 and DQB1*0402 alleles differ only at residue 23, these DQB1 genes are very similar. We next tested cells from these individuals with a particular DQ-specific T-lymphocyte clone, HH58. The clone was only restimulated with cells from Japanese individuals who carried the DQA1*0301 and DQB1*0401 alleles in the cis position or white individuals who carried the DQA1*0301 and DQB1*0402 alleles in the trans position. Thus, particular cis- or trans-encoded DQ alpha beta heterodimers, which in both cases are recognized by T lymphocytes, may confer susceptibility to IDDM in both ethnic groups.
Diabetes 07/1991; 40(6):759-63. · 8.29 Impact Factor
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ABSTRACT: Genomic DNA of HLA class I gene segments was amplified by the polymerase chain reaction (PCR). The amplified 0.8 kb gene segment encompassed sequences corresponding to an exon 2 (alpha 1 domain), an intron 2 and an exon 3 (alpha 2 domain). The PCR product was cloned in M13 and sequenced. Two previously unknown sequences were found. One of them (DAN2) had an open reading frame and intact intron splice sites, but we did not find evidence for transcription. Best homology (87.5%) was found with HLA-BeWo C.1, a recently described HLA-C gene. The other sequence (DAN4) is derived from a pseudogene, because the putative 3' splice site of intron 2 was changed from AG to ATG and the sequence corresponding to exon 3 had a shift in reading frame resulting in a stop codon.
Tissue Antigens 02/1991; 37(1):16-20. · 2.59 Impact Factor
