[Porphyria cutanea tarda. An analysis of HFE gene mutations, hepatitis viruses, alcohol intake, and other risk factors in 54 patients from Guipúzcoa, Basque Country, Spain]. / Porfiria cutánea tarda: asociación con mutaciones HFE, hepatitis virales, alcohol y otros factores de riesgo en Guipúzcoa, País Vasco.

AIM: To study the frequency of HFE gene mutations (C282Y, H63D, S65C) in a group of 54 sporadic PCT patients and in a group of healthy controls (blood donors) from Guipúzcoa, Spain. We studied the association of PCT with HCV, HBV, alcohol abuse, and other established risk factors. METHODS: The analysis of mutations was made by PCR. Allelic and genotypic frequencies were compared. Probability was determined and a Chi-squared test was performed. RESULTS: No association was observed between C282Y mutation and PCT (5.76 vs. 5% in controls). A high H63D mutation frequency was observed in PCT (34.25%) but was not statistically significant (controls 29.31%) because of the high prevalence of this mutation in the Basque general population. The S65C mutation was lower in PCT than in controls. There is a similar presence for H63D heterozygosis in PCT (38.8 vs. 38.8%). HCV association was observed in 35.18% of patients with PCT. HBV infected 7.4% of patients. Heavy alcohol intake (> 60 g/day) was present in 55.55% of patients. No HIV-infected patients were detected. The study of other risk factors revealed only one of the five women with PCT taking estrogens. CONCLUSION: Our results found no relevant role for C282Y and H63D mutations. External factors such as HCV and alcohol could be determinant in the development of PCT in the Basque population.

Two new HLA class I alleles described in a Spanish individual, HLA-A*11:01:01:04 and HLA-B*35:330.

Two new HLA class I alleles, HLA-A*11:01:01:04 and HLA-B*35:330, were characterized in a Spanish patient.

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.

Exon-2 nucleotide sequences, polymorphism and haplotype distribution of a new HLA-DRB gene: HLA-DRB sigma.

Two new allelic exon-2 HLA-DRB sequences have been identified by using universal and also specific DRB primers. They may correspond to a previously unidentified DRB gene (DRB sigma) and define a new supratypic group ("DRw54") which includes DR1, DR"Br", DR2 and DRw10 bearing HLA haplotypes. This is probably the last HLA-DRB gene to be described in the standard DR haplotypes on the bases of the number of TaqI RFLPs obtained. Sequence comparison with their respective DP and DQ sequences shows that DRB sigma is unequivocally placed within the DRB family and also a constructed "neighbouring homology tree" indicates that DRB sigma gene is probably the eldest in the DRB family, thus the first to diverge from the ancestral DRB gene. An hypothetically deduced DRB sigma beta 1 protein domain was found to be quite different from the corresponding DRB1, DRB3, DRB4 and DRB5 products, since residues 40-55 would bear a longer alpha-helical conformation and would also exist a loss of both the extended conformation at residues 50-54 and the alpha-helix at residues 64-71. Thus, the putative DRB sigma protein would be remarkably different to other DRB ones. Also, a DRB sigma partial transcript (exon-2) has been obtained by PCR of cDNA by using specific DRB sigma oligonucleotides, but a specific Northern blot hybridization has not been achieved.

HLA-A*2402 and a microsatellite (D6S248) are secondary independent susceptibility markers to ankylosing spondylitis in Basque patients.

Ankylosing spondylitis (AS) is universally associated with human leukocyte antigen B27 (HLA-B27), although other genes could determine the development and clinical expression of the disease. HLA-A9 (A*2402) allele was previously found to be associated in Basque patients. The objective of this study is to perform a more precise analysis of microsatellite polymorphisms in HLA-A*2402 and B27 haplotypes to elucidate the significance of this association. A group of 50 unrelated AS patients and 113 controls of Basque origin were studied. Eight microsatellites in the class I major histocompatibility complex region with vicinity to HLA-A and -B were analyzed and the strength of allelic associations to AS and linkage disequilibrium (LD) between alleles were evaluated. Allele 15 at the microsatellite locus D6S248, 1000 Kb telomeric to HLA-A showed a strong positive association with the disease (OR:6; pc=4.7x10(-4)) and it could not be explained by LD to HLA-B27, HLA-A*2402 or any other loci. We found that D6S248-15 allele together with HLA-A*2402 could be B27-independent markers of additional susceptibility gene/s localised in the region telomeric to HLA-A in Basque AS patients.

Immunogenetics of systemic lupus erythematosus in Spanish patients: differential HLA markers.

HLA-DR3 antigen included in the compound phenotype B18BfF1 (but not the one linked to the B8BfS compound phenotype) was found to be significantly increased in our SLE patients. It is remarkable that in our Southern-Mediterranean population, B18BfF1DR3 individuals (but not B8BfSDR3) are prone to SLE with renal disease, in contrast with other Northern European and Caucasoid populations. Also, patients with autoantibodies to Ro/La have a significant increase of the B8DR3 compound phenotype. Production of autoantibodies against Ro alone was associated to DR2 and production of anti-Sm/nRNP to DR3 (either B18BfF1 or B8BfS associated) only in the subgroup without renal disease. The distinctive HLA and autoimmune associations to SLE with and without renal disease suggests that both clinical forms may not share a common identical pathogenesis.

[Autoimmune hepatitis with antibodies against liver cytosol (anti-LC1)]. / Hepatitis autoinmune con anticuerpos contra el citosol hepático (anti-LC1).

Antibody against liver cytosol (anti-LC1) was proposed in 1988 as a new and very specific immunoserologic marker of autoimmune hepatitis of childhood and young age. In adults, anti-LC1 might be masked by the presence in serum of anti-LKM1, usually associated with antibodies to hepatitis-C virus. We report the case of a 60-year-old woman who had active chronic hepatitis not related to infection by hepatitis C virus, with autoantibody reacting against liver cytosol as the unique marker of autoimmune hepatitis. Treated with corticosteroids (prednisone, 1 mg/kg per day), coagulation disorder, bilirubin, transaminase activity and immunoglobulins normalized in the following months. A year and a half later, autoantibodies anti-LC1 and p-ANCAs were no longer detected. We have only found one report of a young patient with anti-LC1 autoimmune hepatitis who had cirrhosis and portal hypertension, in national publications.

DNA staining changes associated with apoptosis and necrosis in blood lymphocytes of individuals with HIV infection.

We used flow cytometry to quantitate cells that die by apoptosis or necrosis. The method uses low concentrations of two DNA binding dyes that allow one to establish selective regions for live, apoptotic, and necrotic cells in a rat thymocytes model. Quantitative analysis of blood lymphocyte death in individuals with HIV infection by this technique shows the presence of nonviable cells that exhibit a spectrum of changes in staining by DNA binding dyes. These changes range from typical features of cells undergoing programmed cell death or apoptosis to changes observed in cells that die by accidental death or necrosis. The proportion of cells exhibiting these lethal changes increases significantly in patients who progress to AIDS, but, although cells with staining features associated with apoptosis and necrosis were both found to be increased in in vitro-activated cells from AIDS patients, spontaneous in vivo activation preferentially leads to apoptotic changes without a significant increase of cells exhibiting the staining changes associated with necrosis.

HLA-A*9, a probable secondary susceptibility marker to ankylosing spondylitis in Basque patients.

HLA-B27 is strongly associated to ankylosing spondylitis (AS). The objective of our study was to analyze HLA-B27 association, B27 subtype distribution and frequency of other HLA class I and DR antigens in a group of Basque AS patients. HLA class I antigens were typed serologically and HLA-B27 and A9 subtypes were determined by DNA typing in samples from 46 patients with AS, 54 B27-positive spondyloarthropathies, 82 healthy subjects and 20 B27-positive controls. A class I HLA 9.2 kb PvuII restriction fragment length polymorphism (RFLP), previously associated with AS, was analyzed in a representative group of patients and controls. We found that HLA-B*2705 conferred a relative risk of 126 for AS in this group. HLA-A9 (A*2402) allele was significantly increased in AS patients compared with healthy controls and B27-positive control group (Pcorr<0.0001) and also increased in patients affected with peripheral arthritis. No association between class I HLA 9.2 Kb RFLP and AS was found. These results suggest that HLA-A*9 allele itself or another linked gene could act as a secondary and independent susceptibility allele to AS.

An immunogenetic study of familial scleroderma.

OBJECTIVE: To study the role of the HLA system in the genetic susceptibility to familial systemic sclerosis (SSc). METHODS: HLA class I antigens were determined by classic serological methods and HLA-DRB, -DQA and -DQB genes were analysed by genetic typing in 36 individuals belonging to two families with several individuals affected by SSc. RESULTS: The results did not show any association of the inheritance to SSc with any particular HLA allele in these families but revealed a striking frequency of ANA autoantibodies in healthy spouses of the members of these families. CONCLUSION: The otherwise infrequent familial incidence of SSc does not appear to be primarily linked to the HLA system in this study but it is suggested that other unknown exogenous environmental factors could be implicated in the development of the disease in families.

Complete nucleotide sequence of the HLA-DRB1 *1302 allele.

Sequencing studies of HLA class II molecules have focused almost exclusively on its exon 2. The complete cDNA sequence of the DRB*1302 allele is reported here for the first time. A conservative polymorphism was detected outside the exon 2 at residue 206; these changes can only be recorded if complete cDNA sequences are studied, and may be of value in drawing evolutive inferences.

Association of rheumatoid arthritis with a functional chemokine receptor, CCR5.

OBJECTIVE: To investigate whether the pathogenesis of rheumatoid arthritis (RA) is associated with the functional chemokine receptor CCR5, which is the primary CC chemokine receptor expressed by T cells in rheumatoid synovium, and its nonfunctional receptor, delta32CCR5, which is generated by the homozygous 32-basepair deletion (delta32) in the CCR5 gene. METHODS: The frequency of the CCR5 genotype was compared among 673 patients with RA, 113 patients with systemic lupus erythematosus (SLE), and 815 control subjects. The CCR5 genotype was studied by polymerase chain reaction amplification of the region flanking the delta32 deletion (delta32CCR5). RESULTS: Frequencies of the wild-type CCR5 alleles (0.929, 0.907, and 0.942, respectively) and delta32CCR5 alleles (0.071, 0.093, and 0.058, respectively) in controls, SLE patients, and RA patients did not differ significantly. However, none of the RA patients had the homozygous delta32CCR5 genotype, compared with a frequency of 0.009 in controls (P = 0.014 by Fisher's exact test; chi2 = 4.12 with Yates' correction, P = 0.042) and 0.027 in SLE patients (P = 0.003 by Fisher's exact test; chi2 = 11.63 with Yates' correction, P = 0.0006). CONCLUSION: The results suggest that the CCR5 receptor plays an important role in RA and may be a suitable target for therapy.

The HLA-DRB6 locus defines an evolutionary supratypic group within the DRB family of genes.

A novel DRB gene member has recently been identified (DRB6). It defines a new supratypic group of HLA-DR alleles comprising the DR1-, DR2-, and DRw10-carrying haplotypes. The comparison of this gene either at the nucleotide or at the protein level with other HLA-DRB genes supports its inclusion in the DRB gene family and not in DPB or DQB gene families. Moreover, the construction of an evolutionary gene-tree shows that this gene is probably the eldest member of the DRB gene family. Contradictory expression results do not clarify whether or not DRB6 is a pseudogene.

Differential contribution of HLA-DR, DQ, and TAP2 alleles to systemic lupus erythematosus susceptibility in Spanish patients: role of TAP2*01 alleles in Ro autoantibody production.

OBJECTIVE: To study the influence MHC class II and TAP2 alleles exert on systemic lupus erythematosus (SLE) susceptibility and on the clinical and serological manifestations of the disease, in a cohort of Spanish patients. METHODS: HLA-DR serological typing and HLA-DQA, DQB, and TAP2 DNA sequence specific oligotyping, were carried out in 85 unrelated Spanish SLE patients and 186 healthy controls. Autoantibodies detection was carried out by indirect immunofluorescence and counter immunoelectrophoresis. RESULTS: Total SLE group: the frequency of HLA-DR3 and HLA-DQA1*0501 is significantly increased in this group (pc < 0.005, delta = 0.34 and pc < 0.005, delta = 0.45, respectively) although the highest delta value (delta = 0.87) is obtained when the TAP2*01 alleles are considered. No DQB allele shows significant deviation from the control group. Renal damage: it mainly occurs in HLA-DR3 patients (pc < 0.0005 and delta = 0.72). HLA-DQA1*0501 (p < 0.05, delta = 0.57 and DQB1*0201 (pc NS, delta = 0.56) are weaker susceptibility factors. Ro+ (but not LA) group: this autoantibody response is associated with TAP2*01 alleles in homozygosity (p < 0.05, delta = 0.81). R0/La+ group: it has a different genetic background as HLA-DQA1*0501 (delta = 1) and HLA-DQB1*0201 (delta = 1) are the main susceptibility factors. CONCLUSIONS: A differential association between HLA-DR, DQA1, and DQB1 alleles and SLE or its clinical and serological manifestations are found. Furthermore, the associations are different to the ones reported in other ethnic groups. Finally, TAP2*01 group of alleles are associated with the highest susceptibility to SLE (higher than HLA-DR3) and may influence Ro (but not La) autoantibodies production, whereas HLA-DQA1*0501 and DQB1*0201 mediates concomitant Ro and La productions.