Genomic sequences of HLA-A*68:169, HLA-B*07:298 and HLA-B*39:129.

Three new HLA class I alleles were described in the Spanish population. HLA-A*68:169 and -B*39:129 show one amino acid replacement at the α1-domain, compared to A*68:02 (P47 > L47) and -B*39:06 (S11 > A11), respectively. HLA-B*07:298 presents one nucleotide mutation within exon 1, resulting in a new amino acid position -14, L>Q, which has not been previously described in any HLA protein. Prediction of the B*07:298 signal peptide cleavage did not show significant differences in comparison with that obtained for the rest of HLA-B genes.

Characterization of three new HLA Class I Alleles in Spanish Caucasians, HLA-A*02:620, HLA-B*27:150 and HLA-B*07:05:01:02.

Three new HLA class I alleles, HLA-A*02:620, HLA-B*27:150 and HLA-B*07:05:01:02, were described in the Spanish Caucasoid population.

Exon 2 sequencing of the new HLA-DRB1 allele, DRB1*13:216.

A novel HLA-DRB1*13:216 allele was characterized in a Spanish bone marrow donor.

Report From the First and Second Spanish Killer Immunoglobulin-Like Receptor Genotyping Workshops: External Quality Control for Natural Killer Alloreactive Donor Selection in Haploidentical Stem Cell Transplantation.

An important factor affecting the success in the setting of related haploidentical hematopoietic stem cell transplantation (HSCT) is the graft-versus-leukemia effect mediated by natural killer (NK) cells when the donor displays NK alloreactivity versus the recipient. NK cell function is regulated by killer immunoglobulin-like receptors (KIR) and it has been described that donor KIR genotype influences transplantation outcome. This has led to a requirement of laboratories to have a quality assurance program for validation and control of their KIR genotyping methods. The goal of the 1st and 2nd Spanish KIR Genotyping Workshops was to provide an external proficiency testing program in KIR genotyping for Spanish immunology and transplant laboratories. These workshops were conducted during the years 2014-2016 and consisted of 17 participating laboratories typing a set of 20 samples. The presence/absence of 16 mandatory KIR loci (2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 2DP1, 3DL1, 3DL2, 3DL3, 3DS1, and 3DP1) was evaluated per sample. Methods for KIR genotyping included polymerase chain reaction with the use of sequence-specific primers and sequence-specific oligoprobes. Consensus typing was reached in all samples, and the performance of laboratories in external proficiency testing was satisfactory in all cases. The polymorphism detected in the small sample studied in both workshops is indicative of an ample variety of KIR gene profiles in the Spanish population.

Somatic mutation in the HLA-B gene of a patient with acute myelogenous leukaemia.

In this report we describe a case of somatic mutation in the HLA-B gene in the tumour cells of a patient with acute myelogenous leukaemia (AML). Routine human leukocyte antigen (HLA) typing of patient by serology and molecular methodologies rendered discrepant results regarding the expression of a B*15:01 antigen. Sequencing-based typing of a patient's sample including a very high percentage of blast cells revealed the presence of one nucleotide insertion at exon 3, position 440, codon 123. This insertion resulted in a reading frame shift and a premature stop codon at position 152. The mutation was absent in a sample obtained when the patient was in remission. This case report points out the relevance of the sample source for HLA typing in patients with haematological malignancies.

A novel null HLA-B allele, B*15:375N, due to a seven base pair deletion within exon 3.

Characterization of a novel HLA-B null allele, B*15:375N, with a seven base pair deletion in exon 3.

Three new HLA class II alleles: DRB1*08:70, DQA1*01:13 and DQA1*03:01:03.

Three novel HLA class II alleles, DRB1*08:70, DQA1*01:13 and DQA1*03:01:03, were characterized.

A new HLA-DPB1 allele, HLA-DPB1*142:01, identified in a Peruvian organ donor.

The new HLA-DPB1*142:01 allele differs from DPB1*26:01:02 and DPB1*56:01 at codons 65 (I65>L65) and 35 (F35>Y35), respectively.

Sequencing of a novel HLA-B allele, B*51:153, in a Spanish individual.

HLA-B*51:153 shows two nucleotide differences compared with B*51:08 at codon 163 (CTG>ACG).

Sequencing of the novel HLA-B*49:24 and HLA-DRB1*03:64 alleles.

HLA-B*49:24 shows one nucleotide difference regarding B*49:10 at codon 12 (ATG>GTG). DRB1*03:64 differs from DRB1*03:01:01 in one amino acid residue at position 59, E>Q.

Genomic full-length analysis of the B*08:79 allele suggests exon shuffling involving the B*08:01:01 and B*07:06 alleles.

B*08:79 is composed by partial B*08:01:01 and B*07:06 sequences because of a possible recombination event within intron 2.

Sequencing of a single HLA-B genotype including two rare alleles allows the detection of a new allele, B*44:130.

The novel HLA-B*44:130 allele was found in a Spanish donor. B*44:130 differs from B*44:40 by four nucleotide changes at codons 11, 12 and 24, producing three amino acid replacements, 11A>S, 12M>V and 24T>S.

The new HLA-C allele C*07:170 shows a new polymorphism at amino acid position 147.

The new HLA-C allele C*07:170 differs from C*07:01:01 by two nucleotides at exon 3.

HLA-B*0777 allele differs from B*0707 by a single residue in the antigen binding groove.

Human leukocyte antigen (HLA) class I sequence-based typing (SBT) for hematopoietic unrelated donor searching in a Romanian Caucasian patient showed the presence of a novel HLA-B allele defined as B*0777. HLA-B*0777 has two nucleotides changes at the same codon from B*0707, resulting an amino acid replacement 99Y > 99S.

Allelic distribution and the effect of haplotype combination for HLA type II loci in the celiac disease population of the Valencian community (Spain).

The association between human leukocyte antigen (HLA) class II antigens and celiac disease (CD) was analyzed in a Spanish population. No association with DRB1*04 and DQB1*0302 was noted. The main associated haplotype (70.8%) was DRB1*03-DQB1*0201-DQA1*0501(DR3-DQ2), followed by DRB1*07-DQB1*0202-DQA1*0201 (DR7-DQ2) haplotype, which is associated with DRB1*11-DQB1*0301-DQA1*0505 (DR11-DQ7). The combinations of DR3-DQ2 with DR7-DQ2, and DR7-DQ2 with DR11-DQ7, present a twofold risk compared with each haplotype in homozygosis. An independence test in DR3-DQ2 haplotype found that association with CD was attributable to the whole haplotype, but for DR7-DQ2 was secondary to DQB1/DQA1. There is no need of a double gene dosage to increase the risk. CD-associated alleles typing demonstrates a very high negative predictive value to exclude CD in risk groups.

The effect of in vitro ã-irradiation on mitogenic responsiveness of murine lymphocytes

The objective of this study was to analyze the proliferative response of BALB/cmice lymphocytes after in vitro irradiation (0.05 to 6 Gy). The capability of irradiatedlymphocytes for proliferating without any stimulation and after activation withspecific T and B cell mitogens has been evaluated. The results show that ionizingradiation significantly inhibits spontaneous cellular proliferation and that induced bymitogens and that variations in the degree of inhibition are found depending on theinducing proliferation mitogens and the dosage applied. The conclusion drawn is thatdifferent lymphocyte populations have different radiosensitivities, being B cells moresensitive to ionizing irradiation than T cells. Besides, the effects of gamma-irradiationvary according to the different subpopulations of T cells or, alternatively, to differentT-dependent activation mechanisms (AU)

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The effect of in vitro gamma-irradiation on mitogenic responsiveness of murine lymphocytes.

The objective of this study was to analyze the proliferative response of BALB/c mice lymphocytes after in vitro irradiation (0.05 to 6 Gy). The capability of irradiated lymphocytes for proliferating without any stimulation and after activation with specific T and B cell mitogens has been evaluated. The results show that ionizing radiation significantly inhibits spontaneous cellular proliferation and that induced by mitogens and that variations in the degree of inhibition are found depending on the inducing proliferation mitogens and the dosage applied. The conclusion drawn is that different lymphocyte populations have different radiosensitivities, being B cells more sensitive to ionizing irradiation than T cells. Besides, the effects of gamma-irradiation vary according to the different subpopulations of T cells or, alternatively, to different T-dependent activation mechanisms.

Genetic analyses of celiac disease in a Spanish population confirm association with CELIAC3 but not with CELIAC4.

Genetic predisposition to celiac disease (CD) is determined primarily by the human leukocyte antigen (HLA) genes (CELIAC1 region; 6p21), although many loci are involved in disease susceptibility. First, we have analysed a large series of CD patients from the Spanish Mediterranean region who had previously been characterised for the HLA complex. We have investigated how relevant regions contribute to CD susceptibility: CELIAC3 (CD28/CTLA4/ICOS region on 2q33) and CELIAC4 (19p13) as well as the tumour necrosis factor alpha (TNF-alpha) and the linfotoxin loci by case-control and association analyses. We highlight the association with the +49*A allele of cytotoxic T-lymphocyte-associated antigen 4 locus (P = 0.01), and the -308*A of TNF-alpha locus (P = 0.0008) in DQ2 individuals, although an independent role for TNF-alpha as risk factor has not been proven. Moreover, we do not confirm the association with the CELIAC4 region polymorphisms described in other populations.

HLA class II polymorphisms in Spanish melanoma patients: homozygosity for HLA-DQA1 locus can be a potential melanoma risk factor.

BACKGROUND: The association of melanoma with HLA class II loci is under extensive debate. Different investigators have found discrepant results due to, at least in part, sample size, patient series heterogeneity, choice of control population and differences in the techniques employed for the detection of HLA antigens and alleles. OBJECTIVES: This study was designed to analyse the possible association of melanoma with HLA class II loci with regard to different clinic pathological factors and to investigate other risk factors for melanoma susceptibility, such as HLA homozygosity. PATIENTS AND METHODS: HLA-DRB1, -DQA1 and -DQB1 genotyping was performed for 117 eastern Spanish patients presenting with primary melanoma. RESULTS: Although there were no significant alterations in the phenotypic frequencies of HLA-DQA1, -DQB1 or -DRB1 alleles in any subgroup of patients when compared with controls, patients exhibited a statistically significant increase in HLA-DQA1 homozygosity rate. This DQA1 homozygosity-specific association was particularly dependent on some features in melanoma patients such as light hair colour, skin type I or II, early age at diagnosis, absence of atypical naevi, or abscence of atypical naevus syndrome phenotype (aetiological fractions about 10-20%). Analysis of homozygosity for single DQA1 alleles showed an increased homozygosity rate for DQA1*0505 and DQA1*0301 in comparison with controls. These DQA1 alleles are in strong linkage disequilibrium with DQB1*0301 in white populations, and DQB1*0301 homozygous individuals were significantly increased in red in or fair-haired patients (relative risk 5.65). CONCLUSIONS: Our results indicate that the contribution of HLA class II alleles to primary melanoma incidence is not significant in the Spanish population. However, homozygosity for the HLA-DQA1 locus (and, perhaps, for the HLA-DQB1*0301 allele) might be considered a potential risk factor for developing melanoma depending on the person's genetic background and, perhaps, on certain environmental conditions.