RESUMEN
The new HLA-DPA1*01:182 allele differs from HLA-DPA1*01:03:01:04 by a single mismatch in exon 4.
Asunto(s)
Médula Ósea , Cadenas alfa de HLA-DP , Humanos , Alelos , Brasil , Prueba de HistocompatibilidadRESUMEN
The novel HLA-DPA1*04:03 allele, first described in a potential bone marrow donor from Brazil.
Asunto(s)
Cadenas alfa de HLA-DP , Secuenciación de Nucleótidos de Alto Rendimiento , Alelos , Brasil , Cadenas alfa de HLA-DP/genética , HumanosRESUMEN
Characterization of two novel HLA-DPA1*01:03:01 variants, HLA-DPA1*01:03:01:38 and -DPA1*01:03:01:39.
Asunto(s)
Cadenas alfa de HLA-DP , Alelos , Brasil , Cadenas alfa de HLA-DP/genética , HumanosRESUMEN
Characterization of two novel HLA-DPA1*02:01:01 variants, HLA-DPA1*02:01:01:18 and -DPA1*02:01:01:19.
Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Polimorfismo de Nucleótido Simple , Alelos , Brasil , Cadenas alfa de HLA-DP , HumanosRESUMEN
Characterization and confirmation of the first HLA-DPA1*04:02 variant, called HLA-DPA1*04:02:01:02.
Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Alelos , Brasil , Cadenas alfa de HLA-DP , Humanos , Análisis de Secuencia de ADNRESUMEN
Characterization of three novel HLA-DPA1*02:01:01 variants: HLA-DPA1*02:01:01:14, -DPA1*02:01:01:15, and -DPA1*02:01:01:16.
Asunto(s)
Cadenas alfa de HLA-DP , Alelos , Brasil , Cadenas alfa de HLA-DP/genética , HumanosRESUMEN
Characterization of four novel HLA-DPA1*01:03:01 variants, HLA-DPA1*01:03:01:24, -DPA1*01:03:01:25, -DPA1*01:03:01:26, and -DPA1*01:03:01:27.
Asunto(s)
Cadenas alfa de HLA-DP/genética , Polimorfismo de Nucleótido Simple , Obtención de Tejidos y Órganos , Regiones no Traducidas 3'/genética , Alelos , Trasplante de Médula Ósea , Brasil , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Prueba de Histocompatibilidad/métodos , Humanos , Intrones/genética , Masculino , Análisis de Secuencia de ADN/métodosRESUMEN
BACKGROUND & AIMS: HBV infection exhibits geographical variation in its distribution in South America. While HBV rates are low in central Argentina, the north-western region exhibits intermediate HBV rates. Unfortunately, the reasons that could explain this difference are still unknown. METHODS: A total of 1440 Argentines were recruited and grouped into HBV patients, HBV-resolved individuals and healthy controls. Genetic ancestry was assessed by analysis of biparental lineages and ancestry autosomal typing. SNPs of HLA-DPA1 (rs3077), HLA-DPB1 (rs9277542), HLA-DQB1 (rs2856718) and HLA-DQB2 (rs7453920) were determined, and HBV genotyping was performed by phylogenetic analysis in HBV patients. RESULTS: Native American ancestry prevailed in the north-western region when compared with central Argentina (P<.0001). However, no differences were observed among the three groups of each region. The distribution of HBV genotypes revealed significant differences (P<.0001). Three SNPs (rs3077, rs9277542 and rs7453920) showed a significant association with protection against chronic HBV and viral clearance in both regions. The remaining SNP showed a significant association with susceptibility to chronic HBV. The frequency rates of rs3077-T, related to protection against chronic HBV and viral clearance, were lower in north-western Argentina when compared with central Argentina. The same uneven frequency rates were observed for SNP rs9277542. CONCLUSIONS: This is the first study addressing the associations between the HLA-DP and HLA-DQ loci and the protection against chronic HBV and viral clearance in a multiethnic South American population. The uneven distribution of HLA-DP and HLA-DQ supports the HBV epidemiological differences observed in these two regions of Argentina with dissimilar ancestry genetic background.
Asunto(s)
Antígenos HLA/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Argentina/epidemiología , Distribución de Chi-Cuadrado , Femenino , Frecuencia de los Genes , Genotipo , Antígenos HLA/inmunología , Cadenas alfa de HLA-DP/genética , Cadenas alfa de HLA-DP/inmunología , Cadenas beta de HLA-DP/genética , Cadenas beta de HLA-DP/inmunología , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/inmunología , Cadenas beta de HLA-DQ/genética , Cadenas beta de HLA-DQ/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/etnología , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Interacciones Huésped-Patógeno , Humanos , Desequilibrio de Ligamiento , Modelos Logísticos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Análisis Multivariante , Oportunidad Relativa , Filogenia , Factores Protectores , Factores de RiesgoRESUMEN
BACKGROUND: Low expression of HLA class II antigens has been associated with more aggressive disease in several human malignancies including adult adrenocortical tumors (ACT), but their clinical relevance in pediatric ACT needs to be investigated. PROCEDURE: This study analyzed the expression profile of three class II histocompatibility genes (HLA-DRA, HLA-DPA1, and HLA-DPB1) in 58 consecutive pediatric ACT (13 adenomas and 45 carcinomas) by quantitative real time PCR and their association with clinical and biological features. HLA-DPA1 protein level was determined by immunohistochemistry. RESULTS: A significant association (P < 0.01) was observed between lower expression levels of the three genes analyzed and poor prognostic factors such as age ≥ 4 years, tumor size ≥ 200 cm(3), tumor weight ≥ 100 g, and metastatic disease; the presence of an unfavorable event and death. Underexpression of the HLA-DRA, HLA-DPA1, and HLA-DPB1 genes were associated with lower 5-year event-free survival (EFS) (P = 0.017, P < 0.001, and P = 0.017, respectively). Cox multivariate analysis showed that HLA-DPA1 was an independent prognostic factor (P = 0.029) when analyzed in association with stage IV, age and tumor size. Significantly lower EFS was also observed in patients with negative/weak immunostaining for HLA-DPA1 (P = 0.002). Similar results were observed when only patients classified as having carcinomas were analyzed. CONCLUSION: Our results suggest that lower expression of HLA-DRA, HLA-DPA1, and HLA-DPB1 genes may contribute to more aggressive disease in pediatric ACT. HLA-DPA1 immunostaining may represent potential aggressiveness marker in this tumor.
Asunto(s)
Neoplasias de la Corteza Suprarrenal/inmunología , Cadenas alfa de HLA-DP/genética , Cadenas beta de HLA-DP/genética , Cadenas alfa de HLA-DR/genética , Adolescente , Neoplasias de la Corteza Suprarrenal/mortalidad , Neoplasias de la Corteza Suprarrenal/patología , Niño , Preescolar , Femenino , Cadenas alfa de HLA-DP/análisis , Cadenas beta de HLA-DP/análisis , Cadenas alfa de HLA-DR/análisis , Humanos , Lactante , Masculino , PronósticoRESUMEN
Genetic polymorphism of human leukocyte antigen (HLA)-DPA1 and -DPB1 loci was studied in 154 unrelated individuals from Guadeloupe, an archipelago of five islands located in the Carribean Sea. Thirty different DPB1 and eight different DPA1 alleles were observed with a heterozygosity index of 0.87 and 0.78, respectively. This high degree of heterozygosity corresponds with those found in African populations. The DPB1* 01:01:01 allele was most frequent (0.260), followed by 02:01:02 (0.143) and 04:01:01 (0.127). The DPA1 alleles 01:03 (0.380), 02:01 (0.302), 02:02 (0.175) and 03:01 (0.123) were identified in >35 individuals each, whereas 01:04, 01:05 and 04:01 were present only once. Haplotype estimations revealed the presence of 39 different haplotypes, with DPB1*01:01:01-DPA1*02:02 and DPB1*02:01:02-DPA1*01:03 as the most frequent (0.143 and 0.140, respectively). A striking difference was observed in DPB1/DPA1 associations between DPB1*04:02 and *105:01, that have identical exon 2 sequences. DPB1*04:02 was exclusively associated with DPA1*01:03, whereas DPB1*105:01 was present with DPA1*03:01, *03:02 or *04:01. This implies that the DP molecules are actually different, and this difference is relevant to consider in studies on the function of HLA-DP molecules in transplantation. Overall, HLA-DPA1 and DPB1 allele frequencies and haplotypes of the population of Guadeloupe were most similar to African populations, with characteristic alleles and haplotypes that bespeaks the admixture with other ethnicities.
Asunto(s)
Alelos , Frecuencia de los Genes/genética , Genética de Población , Cadenas alfa de HLA-DP/genética , Cadenas beta de HLA-DP/genética , Haplotipos/genética , Adulto , Secuencias de Aminoácidos , Preescolar , Epítopos/química , Epítopos/inmunología , Femenino , Guadalupe , Humanos , MasculinoRESUMEN
We evaluated the frequency, demographic, clinical, disability evolution and genetic association of HLA DRB1*1501, DRB1*1503, DQA1*0102, DQB1*0602 and DPA1*0301 alleles in patients diagnosed as acute disseminated encephalomyelitis (ADEM) among a population of CNS demyelinating diseases. Fifteen patients (8.4%) of our series were diagnosed as ADEM. The mean age onset was 35.23 years (range 12 to 77), 53.3% were male and follow-up range was 8.5 to 16 years. Two cases (13.3%) had a preceding infection before neurological symptoms, one presented a parainfectious demyelinating, and one case had been submitted to hepatitis B vaccination four weeks before the clinical onset. The EDSS range was 3.0 to 9.5. Eight patients (53.3%) presented MRI with multiple large lesions. CSF was normal in 73.3%. The severe disability observed at EDSS onset improved in 86.66% patients. The genetic susceptibility for ADEM was significantly associated with the HLA DQB1*0602, DRB1*1501 and DRB1*1503 alleles (<0.05) in monophasic ADEM.
Asunto(s)
Encefalomielitis Aguda Diseminada/genética , Frecuencia de los Genes/genética , Antígenos HLA-DP/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Encefalomielitis Aguda Diseminada/patología , Femenino , Genotipo , Cadenas alfa de HLA-DP , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Cadenas HLA-DRB1 , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
Three different Venezuelan Amerindian tribes were studied for human leukocyte antigen (HLA)-DPA1 and DPB1 allelic variability using polymerase chain reaction-sequence-specific oligonucleotide probes (PCR-SSOP) and sequence-based typing in a selected group of samples. These tribes are geographically (two from the Perija Mountain range and one from the Orinoco Delta) and linguistically distinct: the Bari (from Campo Rosario and Saymaidoyi villages) and the Warao have been classified within the Chibcha linguistic family, whereas the Yucpa (from the Aroy, Marewa, and Peraya villages) are Carib speaking. Venezuelan Indians, like other Native American tribes, show a markedly reduced number of different HLA-DP alleles (range, 2-7) and haplotypes (range, 4-11) in comparison with neighboring Venezuelan mestizo and other non-Indian populations. Some HLA-DPB1 (*0402 and *1401) alleles characteristic for all Amerindian tribes are present also in these populations. Despite general similarities, each tribe and, in some cases, some subtribes show their own pattern of allele and haplotype distribution apparently more as a result of linguistic than to geographic variation.