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Antonio Núñez-Roldán

Publications and source records attributed to Antonio Núñez-Roldán.

12 recordsLinked to original sources
PubMed2006

HLA-C and KIR genes in hepatitis C virus infection.

Natural killer (NK) cells are key components of the innate antiviral immune response. NK cell function is regulated by the interaction of major histocompatibility complex class I molecules with NK inhibitory receptors. The aim of this study was to investigate the role of the HLA-C/KIR pair in hepatitis C virus clearance in our population. A total of 196 hepatitis C virus-infected patients (65 resolved and 131 with persistent infection) were included in the study. Genotyping of HLA-C was carried out using polymerase chain reaction followed by a reverse sequence-specific oligonucleotide probe detection system. NK receptor-specific polymerase chain reaction typing of KIR2DL1, KIR2DL2, and KIR2DL3 was performed on the same patient group. Frequencies of the KIR2DL2 gene and the KIR2DL2/KIR2DL2 genotype were lower among patients with persistent infection (32.3% vs 45.4% among resolved, P = 0.01, OR = 0.57, 95% CI = 0.36-0.91; and 16.2% vs 32.3% among resolved, P = 0.02, OR = 0.41, 95% CI = 0.19-0.87). Nevertheless, the frequency of the KIR2DL3 gene was higher among patients with persistent infection (66.9% vs 54.6% among resolved P = 0.02, OR = 1.68, 95% CI = 1.07-2.65). Trends toward lower frequencies of the HLA-C2C2 genotype and NK-HLA interactions with strong and moderate affinity among the patients with persistent infection were also observed.

Cytotoxicity Tests, Immunologic↗
PubMed2006

Molecular defects of the C7 gene in two patients with complement C7 deficiency.

Different genetic mutations have been described in complement components resulting in total or subtotal deficiency states. In this work we report the genetic basis of C7 deficiency in a previously reported Spanish patient exhibiting a combined total deficiency of C7 and C4B associated with systemic lupus erythematosus. Exon-specific polymerase chain reaction and sequencing revealed a not previously described single base mutation in exon 10 (T1458A) leading to a stop codon that causes the premature truncation of the C7 protein (C464X). Additionally, a C to A transversion at position 1561 (exon 11) was found in the patient resulting in an amino acid change (R499S). This latter mutation has been previously reported in individuals with subtotal C7 deficiency or with combined subtotal C6/C7 deficiency from widely spaced geographical areas. Another novel mutation was found in a second patient with meningococcal meningitis of Bolivian and Czech origin; a 11-base pair deletion of nucleotides 631-641 in exon 6 leading to the generation of a downstream stop codon causing the premature truncation of the C7 protein product (T189 x 193). This patient was found to be a heterozygous compound for another mutation in C7; a two-base pair deletion of nucleotides 1922 and 1923, 1923 and 1924 or 1924 and 1925 in exon 14 (1922delAG/1923delGA/1924delAG), leading again to the generation of a downstream stop codon that provokes the truncation of the C7 protein (S620x630). This latter mutation has been recently reported by our group in another Spanish family. Our results provide more evidences for the heterogeneous molecular basis of C7 deficiency.

Adult↗
PubMed2006

Antibodies against glutathione S-transferase T1 in non-solid organ transplanted patients.

BACKGROUND: This article describes the presence of antibodies against glutathione S-transferase T1 (GSTT1) in a group of patients who never received a solid organ graft. These antibodies have been previously detected in liver and kidney transplant subjects with donor-recipient mismatch for this enzyme at the genetic level. In liver-grafted subjects, the appearance of these antibodies correlated with de novo immune hepatitis. STUDY DESIGN AND METHODS: To obtain some insights in this phenomenon, the clinical records of these patients were reviewed, and the possible causes leading to the production of these antibodies and possible clinical consequences were analyzed. RESULTS: The clinical situation of these patients was very heterogeneous, but they had in common the need for transfusions or a previous pregnancy. GSTT1 antigen is present in red blood cells, liver, kidney, and other tissues. Because the presence of the GSTT1-null allele in seven of these patients has been demonstrated, it can be hypothesized that both GSTT1-positive transfusions or pregnancy of a GSTT1-positive fetus could induce these antibodies. Because the recipient is allele-null, no adverse effects in the host are expected to occur. The longest follow-up (5 years) shows no antibody-derived diseases. CONCLUSION: It is concluded that anti-GSTT1 can appear in a context different from the previously published alloreactivity after liver and kidney transplantation, as a consequence of transfusions and pregnancies. So far, no adverse clinical outcomes in our patients have been observed.

Adult↗
PubMed2005

APC germ-line mutations in southern Spanish patients with familial adenomatous polyposis: genotype-phenotype correlations and identification of eight novel mutations.

Familial adenomatous polyposis (FAP) is a disease characterized by the presence of hundreds of adenomatous polyps in the colon and rectum which, if not treated, develop into colorectal cancer. FAP is an autosomal dominantly inherited disorder caused by mutation in the APC gene. The aim of this study was to search for germ-line mutations of the APC gene in unrelated FAP families from southern Spain. By direct sequencing of all APC gene exons, we found the mutation in 13 of 15 unrelated FAP families studied. We identified eight novel mutations: 707delA (exon6), 730_731delAG (exon7), 1787C-->G and 1946_1947insG (exon14), 2496delC, 2838_2839delAT, 2977A-->T, and 3224dupA (exon15). Two patients presented de novo germ-line mutations. Genotype-phenotype correlations for extraintestinal and extracolonic manifestations were studied. Intrafamilial phenotypic variability was observed in two families with mutations in exon/intron boundary, probably due to alternative splicing.

Adenomatous Polyposis Coli↗
PubMed2004

Association of the CT60 marker of the CTLA4 gene with systemic lupus erythematosus.

OBJECTIVE: To investigate the possible association of the CT60A/G marker with systemic lupus erythematosus (SLE) in Spanish patients, and to identify the possible CTLA4 haplotype responsible for the association, taking into account other polymorphisms described at positions -1722T/C, -319C/T, +49A/G, and the microsatellite (AT)(n) in the 3'-untranslated region (3'-UTR) of the CTLA4 gene. METHODS: Genotyping of CT60 was performed in 395 patients with SLE and 293 healthy controls using polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis. Genotyping of the rest of the dimorphisms has been previously reported. Genotyping of microsatellite polymorphism (AT)(n) in the 3'-UTR was performed using PCR with a fluorescence-labeled primer. RESULTS: With regard to CT60A/G, the frequency of the AA genotype was significantly decreased among the SLE patients (18.7% versus 28.3% in the control group; P = 0.003, corrected P [P(corr)] = 0.009, odds ratio [OR] = 0.58, 95% confidence interval [95% CI] 0.40-0.85). In other words, the frequency of individuals bearing the G phenotype was increased in the patient group compared with the control group (81.2% versus 71.7%; P = 0.003, P(corr) = 0.006, OR = 1.71, 95% CI 1.18-2.49). The distribution of allele frequency was also significantly different between patients and controls (P = 0.01, P(corr) = 0.02, OR [for allele G] = 1.32, 95% CI 1.06-1.65). After combining the data on the different polymorphisms, 2 neutral haplotypes were found: +49A;(AT)(7);CT60A and +49G;(AT)(8-19);CT60G. In addition, a susceptibility haplotype was found: +49A;(AT)(>19);CT60G. CONCLUSION: The 3'-UTR of the CTLA4 gene is involved in susceptibility to SLE.

3' Untranslated Regions↗
PubMed2004

CD38 polymorphisms in Spanish patients with systemic lupus erythematosus.

The ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase (CD38) gene is a positional and functional candidate gene for the susceptibility to systemic lupus erythematosus (SLE) because CD38 gene maps in the described SLE risk region 4p15 and CD38 molecule is a leukocyte activation antigen and ectoenzyme involved in numerous immune functions. The aim of this study was to investigate the possible association of the polymorphisms located at positions 182 of intron 1 (C/G) and 418 (C/T, located in exon 3) of the CD38 gene with the susceptibility and clinical features of SLE. Genotyping of 276 Spanish patients with SLE and 194 controls was performed by polymerase chain reaction amplification-refractory mutation system techniques. No association between the polymorphisms studied and the susceptibility to SLE was found. However, when patients were stratified according to their clinical manifestations, a significant increase of CC individuals and a significant decrease of CG individuals among patients with discoid rash (67.9% vs. 53.1% in controls p = 0.02, pc > 0.05, odds ratio [OR] = 1.87, 95% confidence interval [95% CI] 1.05-3.35; and 23.5% vs. 40.2% in controls, p = 0.008, pc = 0.024, OR = 0.46 95% CI 0.24-0.85) were found. Logistic regression analysis identified CC genotype as an independent risk factor for discoid rash among patients with SLE (p = 0.01, OR = 2.23, 95% CI 1.19-4.18). In conclusion, a slight contribution of the polymorphism located in intron 1 of the CD38 gene in the clinical features of SLE could be postulated.

ADP-ribosyl Cyclase↗
PubMed2004

Complement component C7 deficiency in two Spanish families.

Different genetic mutations have been described in complement component C7 deficiency, a molecular defect clinically associated with an increased susceptibility to neisserial recurrent infections. In this work we report the genetic basis of C7 deficiency in two different Spanish families (family 1 and family 2). In family 1, of Gypsy ethnical background, exon-specific polymerase chain reaction and sequencing revealed a not previously described single base deletion of nucleotide 1309 (exon 10) in the patient, as well as in her father, leading to a stop codon that causes the premature truncation of the C7 protein (K416 X 419). Additionally, the patient and her mother displayed a missense mutation at position 1135 (exon 9) located in the first nucleotide of the codon GGG (CGG), resulting in a change of amino acid (G357R). This mutation was firstly described in individuals of Moroccan Sephardic Jewish ancestry and has been also reported among Spaniards. In family 2, another novel mutation was found in homozygosity in two siblings; a two base-pair deletion of nucleotides 1922 and 1923 in exon 14 leading to the generation of a downstream stop codon causing the truncation of the C7 protein product (S620 X 630). Our results provide more evidence for the heterogeneous molecular basis of C7 deficiency as well as for the subsequent susceptibility to meningococcal disease, since different families carry different molecular defects. On the other hand, certain C7 defects appear to be prevalent in individuals from certain populations or living in defined geographical areas.

Adolescent↗
PubMed2003

MCP-1 promoter polymorphism in Spanish patients with rheumatoid arthritis.

To investigate the possible role of the polymorphism located in the regulatory region of monocyte chemoattractant protein-1 (MCP-1) gene in the susceptibility to rheumatoid arthritis (RA), a total of 141 Spanish RA patients and 194 controls, previously typed for human leukocyte antigen DRB1* (HLA-DRB1*), were genotyped for -2518 (A/G) MCP-1 gene polymorphism using polymerase chain reaction-restriction fragment length polymorphism. No association between -2518 (A/G) MCP-1 polymorphism and susceptibility to RA was found. Nevertheless, when patients and controls were stratified according to their HLA shared epitope (SE) status, a significant increase in the frequency of genotype GG was found among SE negative (SE-) patients with respect to both SE positive (SE+) patients and SE- controls (16% versus 4% in SE+ patients, pFisher=0.04, odds ratio [OR]=4.4, 95% confidence interval [95%CI]=1.03-21.48; and 4% in SE- controls, pFisher=0.02, OR=4.13, 95%CI=1.10-15.72). In conclusion, MCP-1 polymorphism is slightly associated with the susceptibility to RA in patients lacking the HLA SE.

Alleles↗
PubMed2003

CTLA4 polymorphism in Spanish patients with systemic lupus erythematosus.

The cytotoxic T-lymphocyte antigen 4 (CTLA4, CD152) gene is a positional and functional candidate gene to susceptibility to systemic lupus erythematosus (SLE) because CTLA4 gene maps in the described SLE risk region 2q33 and CTLA4 molecule has an inhibitory effect on T-cell activation. Several polymorphisms have been described in CTLA4 gene, among them, a T/C change at position -1722, a C/T transition at position -319, and another A/G transition at position +49. The aim of this study was to investigate the possible association of these polymorphisms with the susceptibility to SLE in 276 Spanish autochthonous patients using a healthy control group composed of 194 ethnically matched volunteer bone marrow donors. Genotyping of these CTLA4 positions was performed in SLE patients and controls using a polymerase chain reaction amplification refractory mutation system. The genotypic frequencies were in Hardy-Weinberg equilibrium in all patients. No differences in the distribution of the genotype frequencies between patients and controls were found in any case. Our results from the Spanish autochthonous population differ from those found in the Korean population regarding the involvement of the polymorphism located at -1722 in the susceptibility to SLE.

Antigens, CD↗
PubMed2003

Chemokine receptor CCR2/CCR5 polymorphism in Spanish patients with systemic lupus erythematosus.

OBJECTIVE: To investigate the possible association of CCR2 and CCR5 chemokine receptor gene polymorphisms with the susceptibility, clinical features, and the outcome of systemic lupus erythematosus (SLE). METHODS: We studied 276 patients with SLE and 194 ethnically matched healthy controls. Patients were stratified according to their clinical features and outcome. Genotyping of 190 (A/G) CCR2 and D32CCR5 was performed using polymerase chain reaction techniques. RESULTS: No association between the polymorphisms studied and susceptibility to SLE was found. However, when patients were stratified according to their clinical features, an increase in the frequency of individuals bearing D32CCR5 among patients with anti-dsDNA antibodies was found [15.1% vs 6.4% in negative patients (p = 0.03, pcorr > 0.05, OR 2.61, 95% CI 1.04-7.40) and 8% in controls (p = 0.04, pcorr > 0.05, OR 1.97, 95% CI 0.97-4.11)]. Moreover, a significant increase in the frequency of D32CCR5 individuals was observed among patients with biopsy-proven nephritis [20.5% vs 8.5% in patients without nephritis (p = 0.03, pcorr > 0.05, OR 2.79, 95% CI 0.93-7.70) and 8% in controls (pFisher = 0.04, pcorr > 0.05, OR 2.87, 95% CI 0.97-7.82)]. Regarding the outcome, a higher median severity index was found among patients bearing D32CCR5 (33.5 +/- 17.9 vs 26.6 +/- 17.1 in CCR5/CCR5 individuals; p = 0.04). CONCLUSION: Polymorphisms of CCR2 and CCR5 do not seem to be involved in susceptibility to SLE, although a slight contribution of the CCR5 polymorphism in the production of anti-dsDNA autoantibodies, in the development of lupus nephritis, and in the outcome of the disease could be postulated.

Adolescent↗
PubMedDate not supplied

Juvenile hemochromatosis in a Spanish family.

Juvenile hemochromatosis (JH) is a characteristic form of genetic hemochromatosis with an early onset and severe clinical course leading to death if iron depletion treatment is not timely applied. Clinical complications include liver cirrhosis, heart failure, hypogonadotropic hypogonadism, and diabetes. In the present study we report the first case of JH described in Spain. Biochemical and genetic characteristics of the patient and relatives (parents and siblings) were investigated. No individual presented either the mutation at position 845 of the HFE gene or at position 750 of the TFR2 gene, associated with other types of hemochromatosis. Nevertheless, some individuals were homozygous for the mutation at position 187 of HFE. The hypothetic region of association with JH, located at chromosome 1q, was also investigated and results show that the patient presented a unique genotypic combination in 1q. The only brother with heavy iron deposits in hepatocytes was found to be heterozygous for the JH-associated region and homozygous for the HFE187 gene, suggesting a synergistic effect between both hemochromatosis-associated genes.

Adult↗