RESUMEN
Significantly lower graft survival has been observed among recipients of a third (G3) compared with a first or second kidney transplantation. Because patients awaiting G3 are largely HLA immunized, they are usually transplanted with a high HLA match. Moreover, their rate of acute rejection episodes is similar to a first or second transplantation. Since major histocompatibility complex class I related chain A (MICA) molecules have been proposed as new targets for antibody recognition, we were interested to type donors and recipients for MICA alleles and to study MICA immunization of these patients. Forty-three pairs of donors and recipients were typed for MICA alleles using Luminex technology (LABtype RSSO). MICA alleles showed strong linkage disequilibrium with the B locus: some 4-digit alleles were preferentially associated with a given MICA allele. A greater frequency of patients with 2 MICA mismatches (MM) was observed among patients with rejection (40%), whereas all the graft losses were observed in patients with 0 or 1 MICA MM. MICA immunization was studied using sera from 52 patients collected on day 0 and after transplantation using a Luminex assay (LABScreen). MICA immunization was less frequent than HLA immunization, and MICA donor-specific antibody (DSA) was equally present in functional and failed grafts. These observations confirmed the potential role of MICA immunization in rejection, whereas the poor graft survival among third transplantations could not be explained by MICA incompatibility or immunization.
Asunto(s)
Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Histocompatibilidad , Trasplante de Riñón/inmunología , Cadáver , ADN/genética , ADN/aislamiento & purificación , Humanos , Ganglios Linfáticos/inmunología , Reacción en Cadena de la Polimerasa , Reoperación , Estudios Retrospectivos , Bazo/inmunología , Donantes de TejidosRESUMEN
This communication reports the identification of a new HLA-DRB1*03 allele identified in three members of a Caucasian French family. This new allele has been officially named HLA-DRB1*0321 by the World Health Organization Nomenclature Committee. The complete exon 2 sequence of DRB1*0321 is identical to that of DRB1*0307 except for the first and second nucleotides of codon 37 (TT replacing AA), which lead to the substitution of a tyrosine for a phenylalanine (AAC-->TTC at position 37). The family study showed that this new allele was transmitted into the HLA-A*0101/09, -B*0801/14, -Cw*0701, -DRB1*0321, -DRB3*0101, -DQB1*0503 and -DPB1*0401 haplotype. The complete exon 2 sequence of this new allele has been previously deposited in the EMBL Sequence Database under accession number AF297266.
Asunto(s)
Alelos , Antígenos HLA-DR/genética , Secuencia de Bases , Trasplante de Médula Ósea/inmunología , Exones/genética , Salud de la Familia , Cadenas HLA-DRB1 , Haplotipos , Humanos , Datos de Secuencia MolecularRESUMEN
Using the "Polymerase Chain Reaction-Sequence Specific Oligoprobes" (PCR-SSOp) technique, we studied the HLA-DPB locus in both partners of 59 couples with a history of three spontaneous abortions, and of 38 control couples in order to determine the role of this centromeric region of the major histocompatibility complex (MHC) in the immune reaction needed for a favorable course of pregnancy. As no particular phenotypes were noted, and also neither excessive HLA-DP homozygosity in sterile women nor excessive HLA-DP allele sharing between sterile partners, this MHC class II sub-region would seem to play no role either directly or by linkage disequilibrium, in the development of normal pregnancy.
Asunto(s)
Aborto Habitual/inmunología , Antígenos HLA-DP/genética , Infertilidad/inmunología , Aborto Habitual/genética , Estudios de Casos y Controles , Mapeo Cromosómico , Sondas de ADN de HLA , Femenino , Genes MHC Clase II , Homocigoto , Humanos , Infertilidad/genética , Masculino , Fenotipo , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , EmbarazoRESUMEN
The actual effect of HLA-DR matching in renal transplantation remains controversial. Since DNA analysis has been shown to be more reliable than serological typing, a re-evaluation of the impact of DR-matching on graft prognosis is required. In this study, 224 cadaver kidney transplantations performed in our center were retrospectively matched according to Restriction Fragment Length Polymorphism DR incompatibilities and compared to prospective serological DR-matching. Transplant outcome was evaluated using graft survival, first rejection onset and rejection frequency. In 18.8% individuals, a discrepancy between serology and DNA typing for at least one antigen was noted. Serology particularly failed to type recipients (21.7%) and 43.2% of the total missed antigens were serologically "blank" or unidentified ("X") alleles. A graft survival rate of 100% after one year was observed for transplantations with no DNA DR mismatch (n = 31). Furthermore, there was a definite correlation between DNA matching and (i), the percentage of individuals with one or more than one acute rejection episode (18% and 41.8% at one year for O incompatibility and pooled 1 and 2 incompatibilities respectively, p < 0.05); (ii), the mean of acute rejection per individual (p < 0.001); and (iii), the rejection onset time (p < 0.01). No correlation between serological matching and the acute rejection episodes parameters was noted. Since HLA typing could be performed in less than 2 hrs using new molecular biology techniques, we conclude that prospective DNA typing should improve kidney transplantation outcome in the near future.
Asunto(s)
Antígenos HLA-DR/genética , Trasplante de Riñón/inmunología , Rechazo de Injerto/inmunología , Prueba de Histocompatibilidad , Humanos , Polimorfismo de Longitud del Fragmento de Restricción , Estudios RetrospectivosAsunto(s)
Genes MHC Clase II , Antígenos HLA-B/genética , Antígenos HLA-DP/genética , Antígenos HLA-DQ/genética , Antígeno HLA-DR7/genética , Desequilibrio de Ligamiento/genética , Sondas de ADN de HLA/genética , Femenino , Antígeno HLA-B44 , Haplotipos , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Población Blanca/genéticaAsunto(s)
Enfermedades Autoinmunes/genética , Diabetes Mellitus Tipo 1/genética , Enfermedades del Sistema Endocrino/genética , Antígeno HLA-DR4/genética , Alelos , Enfermedades Autoinmunes/clasificación , Enfermedades Autoinmunes/inmunología , Secuencia de Bases , Diabetes Mellitus Tipo 1/clasificación , Diabetes Mellitus Tipo 1/inmunología , Susceptibilidad a Enfermedades/inmunología , Enfermedades del Sistema Endocrino/inmunología , Frecuencia de los Genes , Genes MHC Clase II , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Población Blanca/genéticaAsunto(s)
Antígenos HLA-D/genética , Antígenos HLA-DR/genética , Antígeno HLA-DR1/genética , Prueba de Histocompatibilidad/métodos , Alelos , Secuencia de Bases , Antígenos HLA-D/inmunología , Antígenos HLA-DR/inmunología , Antígeno HLA-DR1/inmunología , Humanos , Datos de Secuencia Molecular , Oligonucleótidos/genética , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
Among the DR specificities undefined by serology, DR-BON is peculiar because RFLP cannot distinguish it from the well-defined allele DR1 even if the two specificities are very different functionally. The occurrence of two DR-BON-like alleles in the same family, one associated to the DQw5 split of DQw1 and the other associated to the DQw7 split of DQw3, enabled us to compare the properties of these alleles. The RFLP analysis showed a typical DR1-like picture for both alleles when probed with DR beta, but for one of the alleles the DQ beta probe gave a DQw7 pattern. Primary mixed lymphocyte cultures showed weak to moderate stimulation between cells from individuals identical for one haplotype and differing for the DR-blank haplotypes, but by test with cloned reagents we were not able to define differences between the two DR-blank molecules. Two-dimensional gel electrophoresis and spot-test with a probe covering the third hypervariable region of the DRB1 gene showed no difference between the two alleles. We thus think that the two DR alleles are identical and that the stimulation observed in primary cultures probably is caused by incompatibility for DQ and DP or class I.
Asunto(s)
Antígenos HLA-DQ/fisiología , Antígenos HLA-DR/fisiología , Alelos , Electroforesis en Gel Bidimensional , Biblioteca Genómica , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Haplotipos , Humanos , Prueba de Cultivo Mixto de Linfocitos , Linaje , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
The alloimmunization against the platelet PL-A1 antigen is strongly associated with a HLA class II structure in mothers of thrombocytopenic neonates. Most of the immunized women have first been shown to possess the DR3 specificity and subsequently the DRw52 allele. The 18 immunized mothers studied here by restriction fragment length polymorphism analysis had the DRw52a specificity at the DRB3 locus whatever their HLA-DRB1 gene product. This finding strongly suggests that the DRB3 chain is directly involved in the presentation of the PL-A1 antigen to the specific T cell. In addition, the similarities between DR3 and DRw52 structures due to a hypothetical gene conversion event should be considered in order to understand the high frequency of DR3 among the DRw52a-responding women. Alternatively, the high frequency of DR3 among the DRw52-responding mothers might be due to the high responder status associated with the former specificity.
Asunto(s)
Antígenos de Plaqueta Humana , Antígenos HLA-DR , Isoantígenos , Plaquetas/inmunología , Femenino , Ligamiento Genético , Antígenos HLA-DR/genética , Subtipos Serológicos HLA-DR , Antígeno HLA-DR3/genética , Haplotipos , Humanos , Inmunización , Recién Nacido , Integrina beta3 , Isoantígenos/genética , Embarazo , Trombocitopenia/congénito , Trombocitopenia/genética , Trombocitopenia/inmunologíaRESUMEN
We have previously reported a significant increase of HLA-DR4 antigen frequency in giant cell arteritis (GCA). This finding suggested an important role of immunogenetic factors in this syndrome. Recent data suggest that inherited susceptibility to several autoimmune diseases was associated with specific DR4 associated DQ beta alleles. DNAs from 27 DR4 positive patients with GCA were digested with Taq I and Bam HI, analysed on 0.7% agarose gel and hybridized with DR beta, DQ alpha and DQ beta probes. DR beta hybridization produced no variant detectable within DR4. DQ beta probe confirmed two clusters among DR4 associated DQW3 alleles: DQW 3.1 (Bam HI 360 Kb) and DQw 3.2 (Taq I 1.9 Kb and Bam HI 11 Kb). Among our 27 DR4 positive patients, 34% were DQW 3.1 and 66% were DQW 3.2. These frequencies are the same as those observed in healthy controls.
Asunto(s)
Arteritis de Células Gigantes/genética , Antígenos HLA-DR/genética , Antígenos de Histocompatibilidad Clase II/genética , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , ADN/análisis , Antígenos HLA-DQ/genética , Antígeno HLA-DR4 , Humanos , Hibridación de Ácido NucleicoRESUMEN
The purpose of this study was the RFLP characterization of the DRw10 specificity. Twenty-two DRw10 cells were tested: the DNAs were digested by seven restriction enzymes and hybridized with DR beta, DQ beta and DQ alpha probes. Hybridization with DR beta revealed a pattern particular to the DRw10 specificity, with a specific TaqI 12.5Kb fragment. Hybridization with both DQ-specific probes showed that DRw10 is always associated with a special DQw1 subtype: DQw5. Furthermore, at DR and DQ levels, the 22 DRw10 cells behaved homogeneously.
Asunto(s)
Antígenos HLA-DR/genética , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , Alelos , Epítopos/inmunología , Ligamiento Genético , Antígenos HLA-DQ/genética , Antígenos HLA-DR/inmunología , Antígeno HLA-DR1 , Antígeno HLA-DR2 , Antígeno HLA-DR6 , Haplotipos , Humanos , Hibridación de Ácido NucleicoRESUMEN
The characteristics, the origin and the role in the determinism and/or in the course of hepatocellular necrosis of immune disorders in patients with alcoholic liver cirrhosis still remain unclear. In this study, the T-lymphocyte population was determined by sheep-rosette formation and labelling with OKT3-monoclonal antibodies. T-cell subsets were investigated using OKT4 and OKT8 monoclonal antibodies in the peripheral blood of 40 alcoholic patients with cirrhosis (CA) and of 23 non-cirrhotic alcoholic (ANC) patients. The results were compared to those in 34 healthy volunteers. A decrease in the percentage of T-lymphocytes in the two groups of alcoholic subjects was noted. However, this decrease was significant only in the CA group and only when OKT3 antibodies were used as markers. The lymphocyte-subset identified by OKT4 antibodies was decreased as well in the CA and ANC groups; however the OKT8+ subset was significantly decreased in the CA group only (p less than 0.001). No correlation was found between this decrease in OKT8+ subpopulation or between the increased OKT4/OKT8 ratio and all biochemical parameters of hepatic function measured in this study. The significance of this T-cell imbalance in CA has still to be elucidated, concerning both the functional activity of the reduced pool of OKT8+ cells (suppressor or cytotoxic?) and the mechanism of this decrease.