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ABSTRACT: Transplantation with hematopoietic stem cells (HSC) from a donor with a single human leukocyte antigen (HLA) mismatch can be proposed to those patients lacking an HLA identical sibling donor or an unrelated donor matched for the HLA-A, -B, -C, DRB1, DQB1 loci. Incompatibilities at HLA classes I and II loci are associated with an increased risk of graft-versus-host disease (GVHD) and mortality, although no consensus exists yet on the relative importance of specific allele disparities on clinical outcome. Donor search algorithms are now complicated by the growing number of new HLA alleles, in particular those that differ outside the peptide-binding site of the HLA molecules. We report here an in vitro cellular assay to quantify CD8+CD137+ alloreactive cytotoxic T lymphocytes (CTLs) in a one-way mixed lymphocyte reaction. Two unique combinations with a single HLA mismatch in the HLA-B44 serotype differing by one amino acid in the α3 domain were investigated. We show that the B*44:27 versus B*44:02 mismatch was not recognized by CTLs in both directions. At days 10 and 20, the frequency of CD8+CD137+T cells was comparable to that measured in the autologous stimulation (0.3-3.9%). A B*44:02 versus B*44:03 mismatch was, however, well recognized at day 10 (7.2%) and day 20 (17.8%). This is the first demonstration that a single HLA-B mismatch involving a residue outside the peptide-binding site is not recognized in an in vitro functional assay and may probably be considered as a permissive incompatibility in vivo.
Tissue Antigens 03/2013; · 2.59 Impact Factor
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E W Petersdorf,
M Malkki,
K Hsu,
P Bardy,
A Cesbron,
A Dickinson,
V Dubois,
K Fleischhauer,
T Kawase,
A Madrigal,
Y Morishima,
B Shaw,
S Spellman,
E Spierings,
M Stern, J-M Tiercy,
A Velardi,
T Gooley
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ABSTRACT: The International Histocompatibility Working Group is a collaborative international effort to understand the HLA and non-HLA genetics of the transplantation barrier. The Working Group is comprised of experts in the fields of histocompatibility and immunogenetics, hematopoietic cell transplantation and outcomes research. Data for 25 855 unrelated donor transplants were submitted in support of research studies for the 16th International Histocompatibility Workshop. Active investigation is in progress in seven key areas: the impact of HLA matching, role of race and ethnicity, identification of permissible HLA mismatches, haplotype-associated determinants, minor histocompatibility antigens, immune response genes and KIR genetics. New hypotheses for the 16th workshop were developed for immunogenetic studies in cord blood and haploidentical-related donor transplantation.
International Journal of Immunogenetics 12/2012; · 1.29 Impact Factor
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M E Riccio,
S Buhler,
J M Nunes,
C Vangenot,
M Cuénod,
M Currat,
D Di,
M Andreani,
M Boldyreva,
G Chambers, [......],
I Romón Alonso,
A Slavčev,
G Sulcebe,
T Suslova,
M Testi, J-M Tiercy,
A Varnavidou,
B Vidan-Jeras,
A Wennerström,
A Sanchez-Mazas
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ABSTRACT: We present here the results of the Analysis of HLA Population Data (AHPD) project of the 16th International HLA and Immunogenetics Workshop (16IHIW) held in Liverpool in May-June 2012. Thanks to the collaboration of 25 laboratories from 18 different countries, HLA genotypic data for 59 new population samples (either well-defined populations or donor registry samples) were gathered and 55 were analysed statistically following HLA-NET recommendations. The new data included, among others, large sets of well-defined populations from north-east Europe and West Asia, as well as many donor registry data from European countries. The Gene[rate] computer tools were combined to create a Gene[rate] computer pipeline to automatically (i) estimate allele frequencies by an expectation-maximization algorithm accommodating ambiguities, (ii) estimate heterozygosity, (iii) test for Hardy-Weinberg equilibrium (HWE), (iv) test for selective neutrality, (v) generate frequency graphs and summary statistics for each sample at each locus and (vi) plot multidimensional scaling (MDS) analyses comparing the new samples with previous IHIW data. Intrapopulation analyses show that HWE is rarely rejected, while neutrality tests often indicate a significant excess of heterozygotes compared with neutral expectations. The comparison of the 16IHIW AHPD data with data collected during previous workshops (12th-15th) shows that geography is an excellent predictor of HLA genetic differentiations for HLA-A, -B and -DRB1 loci but not for HLA-DQ, whose patterns are probably more influenced by natural selection. In Europe, HLA genetic variation clearly follows a north to south-east axis despite a low level of differentiation between European, North African and West Asian populations. Pacific populations are genetically close to Austronesian-speaking South-East Asian and Taiwanese populations, in agreement with current theories on the peopling of Oceania. Thanks to this project, HLA genetic variation is more clearly defined worldwide and better interpreted in relation to human peopling history and HLA molecular evolution.
International Journal of Immunogenetics 12/2012; · 1.29 Impact Factor
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ABSTRACT: HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 genotyping was performed in a sample of Albanian population from Kosovo. The comparison of the respective allele frequencies through F (st) analysis resulted in a close relationship with the Albanians from Albania, the Bulgarians, FYROM Macedonians and Greeks, while the other neighbouring populations are slightly more distant.
International Journal of Immunogenetics 06/2012; · 1.29 Impact Factor
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ABSTRACT: Pre-formed and de novo anti-human leukocyte antigen (HLA) antibodies induce antibody-mediated rejection and are also involved in mechanisms leading to chronic graft nephropathy. The detection of anti-HLA antibodies by solid-phase assay (SPA) has revolutionized the management of immunized patients before and after kidney transplantation. Characterized by high sensitivity and specificity, the clinical relevance of anti-HLA antibodies by SPA has to be clarified. The presence of donor-specific antibody at the epitope level, their titer, and the use of different crossmatch technologies could help to determine which of the anti-HLA antibodies are friends and which are foes in kidney transplantation. In this review, we summarize the current state of the art on this debated topic, and give clinical guidelines for the management of antibody detection pre- and post-transplantation, based on these evidences and our own clinical expertise.
Tissue Antigens 05/2012; 79(5):315-25. · 2.59 Impact Factor
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A Sanchez-Mazas,
B Vidan-Jeras,
J M Nunes,
G Fischer,
A-M Little,
U Bekmane,
S Buhler,
S Buus,
F H J Claas,
A Dormoy, [......],
C Papasteriades,
F Poli,
M E Riccio,
M Spyropoulou Vlachou,
G Sulcebe,
S Tonks,
M Toungouz Nevessignsky,
C Vangenot,
A-M van Walraven, J-M Tiercy
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ABSTRACT: HLA-NET (a European COST Action) aims at networking researchers working in bone marrow transplantation, epidemiology and population genetics to improve the molecular characterization of the HLA genetic diversity of human populations, with an expected strong impact on both public health and fundamental research. Such improvements involve finding consensual strategies to characterize human populations and samples and report HLA molecular typings and ambiguities; proposing user-friendly access to databases and computer tools and defining minimal requirements related to ethical aspects. The overall outcome is the provision of population genetic characterizations and comparisons in a standard way by all interested laboratories. This article reports the recommendations of four working groups (WG1-4) of the HLA-NET network at the mid-term of its activities. WG1 (Population definitions and sampling strategies for population genetics' analyses) recommends avoiding outdated racial classifications and population names (e.g. 'Caucasian') and using instead geographic and/or cultural (e.g. linguistic) criteria to describe human populations (e.g. 'pan-European'). A standard 'HLA-NET POPULATION DATA QUESTIONNAIRE' has been finalized and is available for the whole HLA community. WG2 (HLA typing standards for population genetics analyses) recommends retaining maximal information when reporting HLA typing results. Rather than using the National Marrow Donor Program coding system, all ambiguities should be provided by listing all allele pairs required to explain each genotype, according to the formats proposed in 'HLA-NET GUIDELINES FOR REPORTING HLA TYPINGS'. The group also suggests taking into account a preliminary list of alleles defined by polymorphisms outside the peptide-binding sites that may affect population genetic statistics because of significant frequencies. WG3 (Bioinformatic strategies for HLA population data storage and analysis) recommends the use of programs capable of dealing with ambiguous data, such as the 'gene[rate]' computer tools to estimate frequencies, test for Hardy-Weinberg equilibrium and selective neutrality on data containing any number and kind of ambiguities. WG4 (Ethical issues) proposes to adopt thorough general principles for any HLA population study to ensure that it conforms to (inter)national legislation or recommendations/guidelines. All HLA-NET guidelines and tools are available through its website http://hla-net.eu.
International Journal of Immunogenetics 04/2012; · 1.29 Impact Factor
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V Dubois,
F Sloan-Béna,
A Cesbron,
B G Hepkema,
K Gagne,
S Gimelli,
D Heim,
A Tichelli,
J Delaunay,
M Drouet,
S Jendly,
J Villard, J-M Tiercy
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ABSTRACT: Although acquired uniparental disomy (aUPD) has been reported in relapse acute myeloid leukemia (AML), pretransplant aUPD involving chromosome 6 is poorly documented. Such events could be of interest because loss of heterozygosity (LOH) resulting from aUPD in leukemic cells may lead to erroneous results if HLA typing for hematopoietic stem cell donor searches is performed on blood samples drawn during blastic crisis. We report here six AML patients whose HLA typing was performed on DNA extracted from peripheral blood obtained at diagnosis. We observed LOH involving the entire HLA region (three patients), HLA-A, B, C (two patients) and HLA-A only (one patient). An array-comparative genomic hybridization showed that copy number was neutral for all loci, thus revealing partial aUPD of chromosome 6p21. When HLA typing was performed on remission blood samples both haplotypes were detected. A 3-4% LOH incidence was estimated in AML patients with high blast counts. Based on DNA mixing experiments, we determined by PCR sequence-specific oligonucleotide hybridization on microbeads arrays a detection threshold for HLA-A, B, DRB1 heterozygosity in blood samples with <80% blasts. Because aUPD may be partial, any homozygous HLA result should be confirmed by a second typing performed on buccal swabs or on blood samples from the patient in remission.
Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 03/2012; 26(9):2079-85. · 8.30 Impact Factor
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Florence Bettens,
Jakob Passweg,
Urs Schanz,
Yves Chalandon,
Dominik Heim,
Tayfun Güngör,
Georg Stussi,
Grazia Nicoloso,
Helen Baldomero,
Alois Gratwohl, Jean-Marie Tiercy
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ABSTRACT: Hematopoietic stem cell transplantation (HSCT) with HLA-A, -B, -C, -DRB1, -DQB1 allele matched (10 of 10) unrelated donors is still associated with a significant rate of posttransplantation complications. In order to disclose additional immunogenetic factors, we analyzed the impact of HLA-DPB1 disparities and major histocompatibility complex (MHC)-resident microsatellite polymorphisms in 246 HLA 10 of 10 matched HSCT patients. First we showed that patients with more frequent/conserved HLA haplotypes had a higher 5-year survival (55% ± 18% versus 39% ± 18%, P = .021). In addition, DPB1 incompatibilities and 3 microsatellite alleles were associated with outcome. In a Cox regression model adjusting for European Blood and Marrow Transplant (EBMT) risk score, T cell depletion, and year of treatment, HSCT with a tumor necrosis factor d (TNFd) 4/d5-positive donor was associated with increased mortality (hazard ratio [HR] = 2.03; confidence interval [CI] 1.25-3.31; P = .004), whereas the D6S510-184 allele was protective (HR = 0.44; CI 0.22-0.87; P = .018). The 2 MHC-linked genetic donor factors, DPB1 mismatch (MM), and TNFd4/d5-positivity, acted in synergy with the EBMT risk score with an always lower survival (HR = 2.97; CI 1.27-6.92; P = .012). These data show that multiple MHC-linked genetic donor factors impact on outcome after unrelated donor HSCT. Their additive and potentially divergent effects could explain previous discrepant results, particularly with respect to the role of HLA-DPB1 disparities. We conclude that HLA-DPB1 typing combined with a simple TNFd microsatellite genotyping assay may significantly help in pretransplantation risk assessment for graft-versus-host disease and mortality, particularly for patients with several potential 10 of 10 matched donors.
Biology of blood and marrow transplantation: journal of the American Society for Blood and Marrow Transplantation 09/2011; 18(4):608-16. · 3.15 Impact Factor
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J-M Tiercy
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ABSTRACT: Polymorphisms of short tandem repeats of <10 nucleotides, or microsatellites (Msat), are largely used for post-transplant chimerism analyses in clinical hematopoietic stem cell transplantation (HSCT). Compared to single nucleotide polymorphisms (SNP), they have the advantage of a higher degree of allelic polymorphism and thus a potentially larger degree of informativity. Msat markers contribute to approximately 3% of the human genome and have been highly informative in disease association studies, population genetics, forensic medicine and organ and HSC transplantation. They allowed to expand our knowledge of the haplotypic structure of the HLA complex, including the noncoding sequences in the MHC, and to reach a better characterization of immunological phenotypes. Among the different immunogenetic studies in HSCT patients reviewed here, four Msat loci linked to cytokine genes have been analysed by a number of laboratories as potential candidates markers for HSCT outcome: IFNG, TNFd, IL-10(-1064) and IL-1RN. The low patient numbers and high diversity of clinical parameters account for some heterogeneity of the results. Among the trends starting to emerge from these studies, specific TNFd Msat alleles seem to be associated with acute graft-versus-host disease and mortality. Patient/donor Msat incompatibilities have also been used as surrogate markers to map biologically relevant polymorphisms, with a main focus on MHC-resident genetic variation. High throughput SNP typing and next-generation sequencing technologies will allow acquisition of large-scale genomic data and should allow refined analyses of clinically relevant genotypes in the transplantation settting, although the heterogeneity of the study cohorts will remain an issue. The analysis of Msat polymorphisms may still have a place in functional studies on the impact of Msat diversity in the control of immune response gene expression.
International Journal of Immunogenetics 08/2011; 38(5):365-72. · 1.29 Impact Factor
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S G E Marsh,
E D Albert,
W F Bodmer,
R E Bontrop,
B Dupont,
H A Erlich,
M Fernández-Viña,
D E Geraghty,
R Holdsworth,
C K Hurley, [......],
W R Mayr,
C R Müller,
P Parham,
E W Petersdorf,
T Sasazuki,
J L Strominger,
A Svejgaard,
P I Terasaki, J M Tiercy,
J Trowsdale
Tissue Antigens 04/2010; 75(4):291-455. · 2.59 Impact Factor
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S G E Marsh,
E D Albert,
W F Bodmer,
R E Bontrop,
B Dupont,
H A Erlich,
M Fernández-Viña,
D E Geraghty,
R Holdsworth,
C K Hurley, [......],
W R Mayr,
C R Müller,
P Parham,
E W Petersdorf,
T Sasazuki,
J L Strominger,
A Svejgaard,
P I Terasaki, J M Tiercy,
J Trowsdale
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ABSTRACT: The WHO Nomenclature Committee for Factors of the HLA System met during the 15th International Histocompatibility and Immunogenetics Workshop in Buzios, Brazil in September 2008. This update is an extract of the main report that documents the additions and revisions to the nomenclature of human leukocyte antigen (HLA) specificities following the principles established in previous reports.
Bone marrow transplantation 03/2010; 45(5):846-8. · 3.00 Impact Factor
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J M Nunes,
M E Riccio,
S Buhler,
D Di,
M Currat,
F Ries,
A J Almada,
S Benhamamouch,
O Benitez,
A Canossi, [......],
D Piancatelli,
M Rahal,
L Richard,
M Romero,
J Rousseau,
M Spiroski,
G Sulcebe,
D Middleton, J-M Tiercy,
A Sanchez-Mazas
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ABSTRACT: During the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), 14 human leukocyte antigen (HLA) laboratories participated in the Analysis of HLA Population Data (AHPD) project where 18 new population samples were analyzed statistically and compared with data available from previous workshops. To that aim, an original methodology was developed and used (i) to estimate frequencies by taking into account ambiguous genotypic data, (ii) to test for Hardy-Weinberg equilibrium (HWE) by using a nested likelihood ratio test involving a parameter accounting for HWE deviations, (iii) to test for selective neutrality by using a resampling algorithm, and (iv) to provide explicit graphical representations including allele frequencies and basic statistics for each series of data. A total of 66 data series (1-7 loci per population) were analyzed with this standard approach. Frequency estimates were compliant with HWE in all but one population of mixed stem cell donors. Neutrality testing confirmed the observation of heterozygote excess at all HLA loci, although a significant deviation was established in only a few cases. Population comparisons showed that HLA genetic patterns were mostly shaped by geographic and/or linguistic differentiations in Africa and Europe, but not in America where both genetic drift in isolated populations and gene flow in admixed populations led to a more complex genetic structure. Overall, a fruitful collaboration between HLA typing laboratories and population geneticists allowed finding useful solutions to the problem of estimating gene frequencies and testing basic population diversity statistics on highly complex HLA data (high numbers of alleles and ambiguities), with promising applications in either anthropological, epidemiological, or transplantation studies.
Tissue Antigens 03/2010; 76(1):18-30. · 2.59 Impact Factor
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D Middleton,
F Gonzalez,
M Fernandez-Vina, J-M Tiercy,
S G E Marsh,
M Aubrey,
M G Bicalho,
A Canossi,
V Carter,
S Cate, [......],
V Morales,
J Perasaari,
M Setterholm,
M Sprague,
S Tavoularis,
M Torres,
S Vidal,
C Witt,
G Wohlwend,
K L Yang
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ABSTRACT: A project of the 15th International Histocompatibility Workshop examined the rarity of human leukocyte antigen (HLA) alleles. A section was constructed in the website, www.allelefrequencies.net to contain this data from different sources. A mechanism to search the data was implemented for use by any individual.
Tissue Antigens 09/2009; 74(6):480-5. · 2.59 Impact Factor
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ABSTRACT: Human leucocyte antigen (HLA) alleles are very interesting markers in identifying population relationships. Moreover, their frequency distribution data are important in the implementation of donor-recipient registry programs for transplantation purposes and also in determining the genetic predisposition for many diseases. For these reasons, we studied the HLA class I and II allele and haplotype frequencies in 160 healthy, unrelated Albanian individuals originating from all regions of the country. The HLA genotyping was performed through a 2-digit resolution SSOP method. The data were analysed with Arlequin and Phylip programs. No deviation was found from the Hardy-Weinberg equilibrium. A total of 17 A*, 30 B*, 12 Cw*, 13 DRB1* and 5 DQB1* alleles were identified. The six most frequent HLA-A-B-DRB1 haplotypes were A*02-B*18-DRB1*11 (5.60%), A*02-B*51-DRB1*16 (4.74%), A*01-B*08-DRB1*03 (3.48%), A*24-B*35-DRB1*11 (2.77%), A*02-B*51-DRB1*13 (2.21%), A*24-B*35-DRB1*14 (1.89%). Interestingly, 12 HLA-A-B-Cw-DRB1-DQB1 haplotypes occurred at a frequency >1%. When compared with the other populations, a close relationship was found with North Greek, Bulgarian, Macedonian, Romanian, Turkish, Cretan, Serbian, Croatian and Italian populations. A higher differentiation in allele frequency level was found with Western Europe populations. These data are the first report of HLA allele and haplotype distribution in an Albanian population inside this country. When compared with other populations, their distribution frequencies show close similarities with neighbouring populations of the entire Balkan area.
International Journal of Immunogenetics 08/2009; 36(6):337-43. · 1.29 Impact Factor
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ABSTRACT: In unrelated hematopoietic stem cell transplantation (HSCT), human leukocyte antigen (HLA)-C locus incompatibilities occur frequently and are associated with increased risk of posttransplant complications. Because HLA-B51 is associated with a high rate of Cw disparities, we performed a comprehensive four-digit typing analysis of 140 ABCDRB1 B51 genotypes proven by pedigree analysis and 311 unrelated donors selected for 75 B51-positive patients. In addition, 145 A1/Ax-B8/B51-DR3/DRx donors were HLA typed at a high-resolution level and tested for three microsatellite (Msat) polymorphisms located in the HLA class I and III regions. Based on these data sets, 182 different ABCDR haplotypes with 14 different B-Cw associations were detected. Rates of Cw mismatches were shown to be highly correlated with the ABDRB1 haplotypes. We have computed 21 B51 haplotypes that disclose a high probability of HLA-C allele matching and 30 haplotypes with a low (<25%) probability. The HLA-C allele frequency profiles were quite different in these two groups, with a more heterogeneous distribution in the low matching probability group. HLA-Cw*1502 was inversely correlated with the likelihood to identify a Cw-mismatched donor: it was present in 61% of the high vs 18% of the low probability group (P < 0.0001). The analysis of three Msats in the class I and III regions showed a higher allelic diversity in B51-positive haplotypes compared with the conserved A1-B8-DR3 haplotype. HLA-B51 haplotypes therefore exhibit a high diversity at the level of B-Cw associations and of non-HLA polymorphisms in the class I and III regions. Such heterogeneity negatively impacts on overall matching in HSCT.
Tissue Antigens 05/2009; 73(4):316-25. · 2.59 Impact Factor
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ABSTRACT: We report here the sequence of a new human leucocyte antigen-A2 allele, A*9251, identified in a volunteer haematopoietic stem cell donor of the international registry. A*9251 differs from A*02010101 by two nucleotides at codons 113-114, resulting in a single His>Asp substitution at codon 114.
Tissue Antigens 04/2009; 74(3):248-9. · 2.59 Impact Factor
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K Hadaya,
C de Rham,
C Bandelier,
S Ferrari-Lacraz,
S Jendly,
T Berney,
L Buhler,
L Kaiser,
J D Seebach, J M Tiercy,
P Y Martin,
J Villard
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ABSTRACT: Cytomegalovirus (CMV) infection is the most common viral complication after solid organ transplantation (SOT). Whilst current immunosuppression is known to impair antiviral-specific T-cell immunity in SOT, a potential role for natural killer (NK) cells not affected by immunosuppressive therapy remains to be determined. To address this, we compared the genotype of the NK immunoglobulin-like receptor (KIR) genes and their HLA cognate ligands to the rate of CMV infection in 196 kidney transplant recipients. We have shown that the absence of the HLA-C ligand for inhibitory KIR and the presence of activating KIR genes in the recipients were both associated with a lower rate of CMV infection after transplantation. In a cohort of 17 recipients with acute CMV infection, NK cells were phenotyped over a period of time after diagnosis by their expression profile of C-type lectin receptors and capacity to secrete IFN-gamma. The increased expression of the activating C-type lectin receptors NKG2C and NKG2D was paralleled by the decreased IFN-gamma secretion during the early phase of CMV infection. In conclusion, our findings suggest that KIR/HLA genotype and expression of NKG2C and NKG2D might play a significant role in regulating NK cell function and anti-CMV immunity after kidney transplantation.
American Journal of Transplantation 01/2009; 8(12):2674-83. · 6.39 Impact Factor
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S Meyer-Monard,
J Passweg,
C Troeger,
H-P Eberhard,
E Roosnek,
G Nicoloso de Faveri,
Y Chalandon,
A Rovo,
V Kindler,
O Irion,
W Holzgreve,
A Gratwohl,
C Müller,
A Tichelli, J-M Tiercy
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ABSTRACT: Allogeneic haematopoietic SCT is a standard therapy for many patients with haematological diseases. A major aim of public umbilical cord blood (UCB) banking is to establish an inventory with a large HLA diversity. Few studies have compared HLA diversity between UCB banks and volunteer unrelated donor (VUD) registries and examined whether UCB banks indeed collect more units with rare alleles and haplotypes. This study compares HLA-A/B/DRB1 allele frequencies and inferred A/B/DRB1-haplotypes in 1602 UCB units and 3093 VUD from two centres in distinct recruitment areas in Switzerland. The results show that the frequencies of HLA-DRB1 alleles as well as of the HLA-A/B/DRB1 haplotypes differ between UCB and VUD. Ten DRB1 alleles occurred at a 2- to 12-fold higher relative frequency in UCB than in VUD and 27 rare alleles were identified in UCB. Out of these 27 alleles, 15 were absent in the entire VUD data set of the national registry. This difference in allele frequencies was found only by intermediate/high-resolution typing. Targeted recruitment of UCB units from non-Caucasian donors could further increase HLA allele and haplotype diversity of available donors. Intermediate or high-resolution DNA typing is essential to identify rare alleles or allele groups.
Bone marrow transplantation 01/2009; 43(10):771-8. · 3.00 Impact Factor
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ABSTRACT: While the influence of HLA-AB and -DRB1 matching on the outcome of bone marrow transplantation (BMT) with unrelated donors is clear, the evaluation of HLA-C has been hampered by its poor serological definition. Because the low resolution of standard HLA-C typing could explain the significant number of positive cytotoxic T lymphocyte precursor frequency (CTLpf) tests found among HLA-AB-subtype, DRB1/B3/B5-subtype matched patient/donor pairs, we have identified by sequencing the incompatibilities recognized by CD8+ CTL clones obtained from such positive CTLpf tests. In most cases the target molecules were HLA-C antigens that had escaped detection by serology (e.g. Cw*1601, 1502 or 0702). Direct recognition of HLA-C by a CTL clone was demonstrated by lysis of the HLA class I-negative 721,221 cell line transfected with Cw*160l cDNA. Because of the functional importance of Cw polymorphism, a PCR-SSO oligotyping procedure was set up allowing the resolution of 29 Cw alleles. Oligotyping of a panel of 382 individuals (including 101 patients and their 272 potential unrelated donors, 5 related donors and 4 platelet donors) allowed to determine HLA-C and HLA A-B-Cw-DRB1 allelic frequencies, as well as a number of A-Cw, B-Cw, and DRB1-Cw associations. Two new HLA-Cw alleles (Cw*02023 and Cw*0707) were identified by DNA sequencing of PCR-amplified exon 2-intron 2-exon 3 amplicons. Furthermore, we determined the degree of HLA-C compatibility in 287 matched pairs that could be formed from 73 patients and their 184 potential unrelated donors compatible for HLA-AB by serology and for HLA-DRB1/ B3/B5 by oligotyping. Cw mismatches were identified in 42.1% of these pairs, and AB-subtype oligotyping showed that 30% of these Cw-incompatible pairs were also mismatched for A or B-locus subtype. The degree of HLA-C incompatibility was strongly influenced by the linkage with B alleles and by the ABDR haplotypes. Cw alleles linked with B*4403, B*5101, B18, and B62 haplotypes were frequently mismatched. Apparently high resolution DNA typing for HLA-AB does not result in full matching at locus C. Since HLA-C polymorphism is recognized by alloreactive CTLs, such incompatibilities might be as relevant as AB-subtype mismatches in clinical transplantation.
Tissue Antigens 12/2008; 49(6):612 - 623. · 2.59 Impact Factor
