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1.
Sergio Mercado Cej Lucia Rangel Gambo María Elisa Vega Memije Angélica Olivo Díaz Julio Granados 《Asia-Pacific Journal of Blood Types and Genes》2019,3(2):133-137
Leprosy is a chronic, infectious disease, caused by Mycobacterium leprae, Mycobacterium lepromatosis or both, which affects the peripheral nervous system and the skin. Activation of cellular immunity in infected individuals depends on antigen recognition, which involves relevant HLA-Class II alleles. Therefore, the objective of this study was to determine HLA-Class II allele frequencies (HLA-DRB1and-DQB1)in Mexican Mestizo leprosy patients and compare themwith healthy controls, in order to define their role in the genetic susceptibility to this infection.The genomic DNA of each participant was obtained from peripheral blood, using the salting-out method. PCR amplification and hybridization ofHLA-class II alleleswas made by PCR-SSO. The results showed that frequencies of HLA-DRB1*15(Pc =0.003, OR=3.3 95%CI=1.53-7.33), HLA-DQB1*05(Pc =0.00003, OR=6.03 95%CI=2.49-14.61) and HLA-DQB1*06 (Pc =0.007, OR=2.89, 95%CI=1.38-6.04)were significantly higher among leprosypatients than those of healthy controls. The study suggests that HLA-DRB1*15, HLA-DQB1*05, and HLA-DQB1*06 are associated with leprosy susceptibility in the Mexican Mestizo population. 相似文献
2.
E. Zanelli Tom W. J. Huizinga Pierre-André Guerne Thomas L. Vischer Jean-Marie Tiercy Willem Verduyn Geziena M. T. Schreuder Ferdinand C. Breedveld René R. P. de Vries 《Immunogenetics》1998,48(6):394-401
In the present study, we tested our hypothesis on the role of a DQ-DR haplotype in rheumatoid arthritis (RA) predisposition. Using two groups of patients and controls, one from The Netherlands
and one from Switzerland, we found that DQA1*0301-homozygous and DQA1*0301//DQA1*0101/04-heterozygous individuals are highly
predisposed to RA in both populations, while DQA1*0101/04-homozygous are not. The DQA1*0301-DRB1*0403/06/07 and DQA1*0301-DRB1*0901 haplotypes are not associated with RA by themselves but strongly increase the risk of developing disease in DQA1*0301- and
DQA1*0101/04-heterozygous. DRB1 alleles carrying the motif DERAA in their third hypervariable region, i.e., *0103, *0402, *1102, *1103, *1301, and *1302,
provide a long-lasting protection against RA in DQA1*0101/04- but not in DQA1*0301-positive individuals. These data show that
considering both DQ and DR gives a better distinction between patients and controls than the shared epitope hypothesis.
Received: 5 March 1998 / Revised: 21 April 相似文献
3.
van Lummel M van Veelen PA Zaldumbide A de Ru A Janssen GM Moustakas AK Papadopoulos GK Drijfhout JW Roep BO Koning F 《The Journal of biological chemistry》2012,287(12):9514-9524
HLA-DQ2 and HLA-DQ8 are strongly predisposing haplotypes for type 1 diabetes (T1D). Yet HLA-DQ2/8 heterozygous individuals have a synergistically increased risk compared with HLA-DQ2 or HLA-DQ8 homozygote subjects that may result from the presence of a transdimer formed between the α-chain of HLA-DQ2 (DQA1*05:01) and the β-chain of HLA-DQ8 (DQB1*03:02). We generated cells exclusively expressing this transdimer (HLA-DQ8trans), characterized its peptide binding repertoire, and defined a unique transdimer-specific peptide binding motif that was found to be distinct from those of HLA-DQ2 and HLA-DQ8. This motif predicts an array of peptides of islet autoantigens as candidate T cell epitopes, many of which selectively bind to the HLA transdimer, whereas others bind to both HLA-DQ8 and transdimer with similar affinity. Our findings provide a molecular basis for the association between HLA-DQ transdimers and T1D and set the stage for rational testing of potential diabetogenic peptide epitopes. 相似文献
4.
The spectrum of HLA-DQ and HLA-DR alleles, 2006: a listing correlating sequence and structure with function 总被引:4,自引:4,他引:0
The list of alleles in the HLA-DRB, HLA-DQA, and HLA-DQB gene loci has grown enormously since the last listing in this journal 8 years ago. Crystal structure determination of several human and mouse HLA class II alleles, representative of two gene loci in each species, enables a direct comparison of ortholog and paralog loci. A new numbering system is suggested, extending earlier suggestions by [Fremont et al. in Immunity 8:305-317, (1998)], which will bring in line all the structural features of various gene loci, regardless of animal species. This system allows for structural equivalence of residues from different gene loci. The listing also highlights all amino acid residues participating in the various functions of these molecules, from antigenic peptide binding to homodimer formation, CD4 binding, membrane anchoring, and cytoplasmic signal transduction, indicative of the variety of functions of these molecules. It is remarkable that despite the enormous number of unique alleles listed thus far (DQA = 22, DQB = 54, DRA = 2, and DRB = 409), there is invariance at many specific positions in man, but slightly less so in mouse or rat, despite their much lower number of alleles at each gene locus in the latter two species. Certain key polymorphisms (from substitutions to an eight-residue insertion in the cytoplasmic tail of certain DQB alleles) that have thus far gone unnoticed are highly suggestive of differences or diversities in function and thus call for further investigation into the properties of these specific alleles. This listing is amenable to supplementation by future additions of new alleles and the highlighting of new functions to be discovered, providing thus a unifying platform of reference in all animal species for the MHC class II allelic counterparts, aiding research in the field and furthering our understanding of the functions of these molecules. 相似文献
5.
Wiesner M Stepniak D de Ru AH Moustakis AK Drijfhout JW Papadopoulos GK van Veelen PA Koning F 《Immunogenetics》2008,60(9):551-555
During assembly, HLA class II molecules associate with the invariant chain. As the result, the peptide-binding groove is occupied by an invariant chain peptide termed CLIP (class-II-associated invariant chain peptide; sequence MRMATPLLM). By mass spectrometry, we have now characterized peptides that are naturally present in HLA-DQ2. This analysis revealed that 22 variants of Ii-derived peptides are associated with HLA-DQ2. Strikingly, the large majority of those do not contain the conventional CLIP sequence MRMATPLLM, but instead a peptide that partially overlaps with CLIP, sequence TPLLMQALPM. Peptide binding studies indicate that this alternative CLIP peptide has superior HLA-DQ2 binding properties compared to the conventional CLIP and that the minimal nine-amino-acid binding core consists of the sequence PLLMQALPM, findings that could be corroborated by molecular simulation. The alternative CLIP peptide was also found to be present in HLA-DQ2 molecules isolated from human thymus. Moreover, the alternative CLIP peptide was also found in association with HLA-DQ8. Together, these results indicate that HLA-DQ2 and HLA-DQ8 associate with an alternative CLIP sequence, a property that may relate to the strong association between HLA-DQ molecules and human autoimmune diseases. 相似文献
6.
T-cell recognition of HLA-DQ2-bound gluten peptides can be influenced by an N-terminal proline at p-1 总被引:1,自引:0,他引:1
Stepniak D Vader LW Kooy Y van Veelen PA Moustakas A Papandreou NA Eliopoulos E Drijfhout JW Papadopoulos GK Koning F 《Immunogenetics》2005,57(1-2):8-15
Recent research has implicated a large number of gluten-derived peptides in the pathogenesis of celiac disease, a preponderantly HLA-DQ2-associated disorder. Current evidence indicates that the core of some of those peptides is ten amino acids long, while HLA class II normally accommodates nine amino acids in the binding groove. We have now investigated this in detail, using gluten-specific T-cell clones, HLA-DQ2-specific peptide-binding assays and molecular modelling. T-cell recognition of both a -gliadin peptide and a low-molecular-weight glutenin peptide was found to be strictly dependent on a ten-amino acids-long peptide. Subsequent peptide-binding studies indicated that the glutenin peptide bound in a conventional p1/p9 register, with an additional proline at p-1. Testing of substitution analogues demonstrated that the nature of the amino acid at p-1 strongly influenced T-cell recognition of the peptide. Moreover, molecular modelling confirmed that the glutenin peptide binds in a p1/p9 register, and that the proline at p-1 points upward towards the T-cell receptor. Database searches indicate that a large number of potential T-cell stimulatory gluten peptides with an additional proline at relative position p-1 exist, suggesting that the recognition of other gluten peptides may depend on this proline as well. This knowledge may be of importance for the identification of additional T-cell stimulatory gluten peptides and the design of a peptide-based, tolerance-inducing therapy. 相似文献
7.
Takashi Nishida Naomi Kondo Hiroatsu Agata Osamu Fukutomi Shinji Shinoda Yasuyuki Suzuki Nobuyuki Shimozawa Shunji Tomatsu Tadao Orii 《Biotherapy》1994,8(1):33-40
In order to clarify the mechanism of food-antigen recognition, the proliferative responses of peripheral blood mononuclear cells (PBMCs) to native, heat-denatured or pepsin-treated ovalbumin (OA) were investigated in 16 hen's egg-sensitive patients with atopic dermatitis (AD). Seven of them had hypersensitivity to boiled hen's egg and others had not. The responses of PBMCs to heat-denatured OA were lower than those to native OA in the patients without hypersensitivity to boiled hen's egg. However, there were no differences of the responses of PBMCs between heat-denatured OA and native OA in the patients with hypersensitivity to boiled hen's egg. Moreover, the reduction of the responses of PBMCs to pepsin-treated OA was recognized in six out of seven patients. The primary structure of OA did not change by heating or pepsin treatment according to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). These results suggested that the secondary structure of OA changed in connection with the reduction of the responses of PBMCs to denatured OA. In addition, we demonstrated the suppressive effect of anti-HLA-DR and anti-HLA-DQ monoclonal antibodies on the proliferative response of PBMCs to OA. The results suggested that the proliferative responses of PBMCs to OA were restricted by HLA-DR or HLA-DQ in hen's egg-sensitive patients with AD.Abbreviations AD
atopic dermatitis
- BSA
bovine serum albumin
- OA
ovalbumin
- PBMC
peripheral blood mononuclear cell
- SDS-PAGE
sodium dodecyl sulfate polyacrylamide gel electrophoresis 相似文献
8.
Larrieu P Ouisse LH Guilloux Y Jotereau F Fonteneau JF 《Cancer immunology, immunotherapy : CII》2007,56(10):1565-1575
Melan-A/MART1 is a melanocytic differentiation antigen expressed by tumor cells of the majority of melanoma patients and, as such, is considered as a good target for melanoma immunotherapy. Nonetheless, the number of class I and II restricted Melan-A epitopes identified so far remains limited. Here we describe a new Melan-A/MART-1 epitope recognized in the context of HLA-DQa1*0101 and HLA-DQb1*0501, -DQb1*0502 or -DQb1*0504 molecules by a CD4+ T cell clone. This clone was obtained by in vitro stimulation of PBMC from a healthy donor by the Melan-A51-73 peptide previously reported to contain a HLA-DR4 epitope. The Melan-A51-73 peptide, therefore contains both HLA-DR4 and HLA-DQ5 restricted epitope. We further show that Melan-A51-63 is the minimal peptide optimally recognized by the HLA-DQ5 restricted CD4+ clone. Importantly, this clone specifically recognizes and kills tumor cell lines expressing Melan-A and either HLA-DQb1*0501, -DQb1*0504 or -DQb1*0502 molecules. Moreover, we could detect CD4+ T cells secreting IFN-gamma in response to Melan-A51-63 and Melan-A51-73 peptides among tumor infiltrating and blood lymphocytes from HLA-DQ5+ patients. This suggests that spontaneous CD4+ T cell responses against this HLA-DQ5 epitope occur in vivo. Together these data significantly increase the fraction of melanoma patients susceptible to benefit from a Melan-A class II restricted vaccine approach. 相似文献
9.
Peptide binding motifs and specificities for HLA-DQ molecules 总被引:13,自引:0,他引:13
HLA-DQ molecules have been associated with susceptibility to a number of autoimmune and other diseases, possibly through
the peptide repertoire that can be presented by different allelic products. It is thus of importance to understand which peptides
can be bound by different HLA-DQ allelic products. Recently, a model for HLA-DQ has been described and used to derive peptide positional environments for
HLA-DQ allelic products. By combining the peptide positional environments with known HLA-DQ peptide binding motifs, a set of predictions
of likely anchor motifs for many of the products of HLA-DQ allelic variants are made and presented in a table referred to as a roadmap for HLA-DQ peptide binding specificities.
Received: 3 March 1999 / Revised: 20 May 1999 相似文献
10.