RESUMO
Cytotoxic T-cells generated against heterologous, mucinous pancreatic tumour cells were shown to recognize mucin in a major histocombatibility complex (MHC)-unrestricted fashion. In contrast, the present study demonstrates a typical allogeneic response of heterologous cytotoxic T-cells established against mucin-expressing pancreatic tumour cells. Heterologous cytotoxic T cells lysed targets that were used as stimulators and other targets that shared human leucocyte antigen (HLA) with the stimulator. These cytotoxic T-cells lysed mucin-expressing stimulator cells but not autologous tumour cells in spite of expressing mucin on their surface. Likewise, tumour-infiltrating CD4+ T-cells proliferated against its own tumour cell target, while such T-cells did not respond to heterologous, mucin-expressing pancreatic tumour cells. Culturing heterologous tumour-specific cytotoxic T-cells with purified pancreatic tumour cell-mucin rendered them unresponsive to their target cells. Furthermore, purified mucin did not produce a mucin-specific response in mucinous pancreatic tumour patients' primary T-cells even in the presence of antigen-presenting cells. Our study finds no evidence for MHC-unrestricted recognition of mucin by pancreatic cancer patients' T-cells.
Assuntos
Complexo Principal de Histocompatibilidade , Mucinas/imunologia , Neoplasias Pancreáticas/imunologia , Linfócitos T Citotóxicos/imunologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Células Matadoras Ativadas por Linfocina/imunologia , Neoplasias Pancreáticas/patologia , Células Tumorais CultivadasAssuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Coração/imunologia , Transplante de Rim/imunologia , Transplante de Pulmão/imunologia , Biomarcadores/análise , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Imunidade Celular , Isoanticorpos/sangue , Isoantígenos/imunologia , Sensibilidade e Especificidade , Doadores de Tecidos , Quimeras de Transplante , Transplante Homólogo , Resultado do TratamentoRESUMO
BACKGROUND: The DiGeorge syndrome is a congenital disorder that affects the heart, parathyroid glands, and thymus. In complete DiGeorge syndrome, patients have severely reduced T-cell function. METHODS: We treated five infants (age, one to four months) with complete DiGeorge syndrome by transplantation of cultured postnatal thymus tissue. Follow-up evaluations included immune phenotyping and proliferative studies of peripheral-blood mononuclear cells plus biopsy of the thymus allograft. Thymic production of new T cells was assessed in peripheral blood by tests for T-cell-receptor recombination excision circles, which are formed from excised DNA during the rearrangement of T-cell-receptor genes. RESULTS: After the transplantation of thymus tissue, T-cell proliferative responses to mitogens developed in four of the five patients. Two of the patients survived with restoration of immune function; three patients died from infection or abnormalities unrelated to transplantation. Biopsies of grafted thymus in the surviving patients showed normal morphologic features and active T-cell production. In three patients, donor T cells could be detected about four weeks after transplantation, although there was no evidence of graft-versus-host disease on biopsy or at autopsy. In one patient, the T-cell development within the graft was demonstrated to accompany the appearance of recently developed T cells in the periphery and coincided with the onset of normal T-cell function. In one patient, there was evidence of thymus function and CD45RA+CD62L+ T cells more than five years after transplantation. CONCLUSIONS: In some infants with profound immunodeficiency and complete DiGeorge syndrome, the transplantation of thymus tissue can restore normal immune function. Early thymus transplantation - before the development of infectious complications - may promote successful immune reconstitution.
Assuntos
Síndrome de DiGeorge/cirurgia , Linfócitos T/imunologia , Timo/transplante , Anormalidades Múltiplas/imunologia , Anormalidades Múltiplas/cirurgia , Biópsia , Divisão Celular , Síndrome de DiGeorge/imunologia , Feminino , Humanos , Lactente , Recém-Nascido , Leucócitos Mononucleares/efeitos dos fármacos , Ativação Linfocitária , Masculino , Mitógenos/farmacologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/fisiologia , Timo/citologia , Timo/imunologiaRESUMO
Human interferon-alpha (IFNalpha) and IFNbeta are administered for treatment of several diseases, including viral infections, malignancies, and multiple sclerosis (MS). IFNalpha therapy has been associated with the production of autoantibodies and the development of a variety of autoimmune disorders, including polyarthritis. This report describes the development of seronegative, symmetric polyarthritis in a patient with relapsing-remitting MS, after 8 weeks of therapy with IFNbeta1a. HLA phenotyping analysis of the patient revealed the presence of HLA-DRB1*0404, an allele known to be associated with the development of rheumatoid arthritis. Therefore, IFNbeta1a may have induced arthritis in a patient who was genetically predisposed to develop arthritis on the basis of HLA determinants. The English-language literature regarding IFNalpha- and IFNbeta-induced polyarthritis is reviewed, and possible mechanisms for IFNalpha- and IFNbeta-induced autoimmunity, including the contribution of HLA determinants and nitric oxide overproduction, are discussed.
Assuntos
Artrite/induzido quimicamente , Artrite/terapia , Antígenos HLA-DR/genética , Interferon beta/efeitos adversos , Adjuvantes Imunológicos/efeitos adversos , Idoso , Alelos , Artrite/genética , Feminino , Cadeias HLA-DRB1 , HumanosRESUMO
BACKGROUND: Since 1968 it has been known that bone marrow transplantation can ameliorate severe combined immunodeficiency, but data on the long-term efficacy of this treatment are limited. We prospectively studied immunologic function in 89 consecutive infants with severe combined immunodeficiency who received hematopoietic stem-cell transplants at Duke University Medical Center between May 1982 and September 1998. METHODS: Serum immunoglobulin levels and lymphocyte phenotypes and function were assessed and genetic analyses performed according to standard methods. Bone marrow was depleted of T cells by agglutination with soybean lectin and by sheep-erythrocyte rosetting before transplantation. RESULTS: Seventy-seven of the infants received T-cell-depleted, HLA-haploidentical parental marrow, and 12 received HLA-identical marrow from a related donor; 3 of the recipients of haploidentical marrow also received placental-blood transplants from unrelated donors. Except for two patients who received placental blood, none of the recipients received chemotherapy before transplantation or prophylaxis against graft-versus-host disease. Of the 89 infants, 72 (81 percent) were still alive 3 months to 16.5 years after transplantation, including all of the 12 who received HLA-identical marrow, 60 of the 77 (78 percent) who were given haploidentical marrow, and 2 of the 3 (67 percent) who received both haploidentical marrow and placental blood. T-cell function became normal within two weeks after transplantation in the patients who received unfractionated HLA-identical marrow but usually not until three to four months after transplantation in those who received T-cell-depleted marrow. At the time of the most recent evaluation, all but 4 of the 72 survivors had normal T-cell function, and all the T cells in their blood were of donor origin. B-cell function remained abnormal in many of the recipients of haploidentical marrow. In 26 children (5 recipients of HLA-identical marrow and 21 recipients of haploidentical marrow) between 2 percent and 100 percent of B cells were of donor origin. Forty-five of the 72 children were receiving intravenous immune globulin. CONCLUSIONS: Transplantation of marrow from a related donor is a life-saving and life-sustaining treatment for patients with any type of severe combined immunodeficiency, even when there is no HLA-identical donor.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa/terapia , Linfócitos B/fisiologia , Feminino , Doença Enxerto-Hospedeiro , Teste de Histocompatibilidade , Humanos , Lactente , Recém-Nascido , Células Matadoras Naturais/fisiologia , Depleção Linfocítica , Masculino , Fenótipo , Estudos Prospectivos , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Análise de Sobrevida , Linfócitos T/imunologia , Linfócitos T/fisiologiaRESUMO
ROP trays containing patient serum samples and distributed by the South-Eastern Organ Procurement Foundation (SEOPF) were instituted to increase the likelihood of transplanting potential renal recipients who are highly sensitized to HLA antigens. This study examines kidney distribution and transplant outcome to assess equitable placement and clinical function post transplant with and without the use of ROP trays. Data were collected over a 26-month period on the distribution of kidneys from 328 consecutive SEOPF donors from whom at least 1 kidney was procured. Shared kidneys were placed via the UNOS and SEOPF-variance computer match programs. Of 656 kidneys, 596 were placed into 582 recipients; 60 were not used. ROP trays were used in placement of 492 kidneys and were not used for placement of 104 kidneys. Outcome was determined for 435 kidneys transplanted into SEOPF recipients. Only 33 (6.9%) recipients with ROP tray use and 10 (9.8%) without were sensitized to HLA. A 10% increase in placement to the originally intended recipient was seen with ROP tray usage over kidneys placed without ROP tray use (p < or = 0.025). Recipients matched using ROP tray data averaged 29 positions higher on the match printout. There was no difference in tray use regarding placement of kidneys within or outside the donor's local UNOS region, nor was there a difference in mean HLA match of transplant pairs with and without ROP tray use, 3.2 and 3.1 antigens, respectively. Cold ischemia time was similar, 22.9 and 23.6 h, respectively, for kidneys placed with and without ROP trays. At post-transplant discharge, there were no differences in patient status, graft failure, rejection treatment, dialysis need, or urine output whether or not ROP trays were used. Significantly, however, plasma creatinine at discharge and at 12 months was lower for those placed with ROP trays (2.5 mg/dl and 1.7 mg/dl) vs (3.1 mg/dl and 1.9 mg/dl), respectively. During this time period, all kidneys transplanted with use of ROP trays functioned as well or better than those transplanted without ROP tray placement. Thus, the use of ROP trays appeared to have a beneficial effect in getting more recipients of higher priority transplanted with equivalent, if not better, graft function.
Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos/métodos , Temperatura Baixa , Creatinina/sangue , Bases de Dados como Assunto , Seguimentos , Rejeição de Enxerto/terapia , Sobrevivência de Enxerto , Antígenos HLA/sangue , Histocompatibilidade , Humanos , Transplante de Rim/imunologia , Transplante de Rim/fisiologia , Transplante de Rim/estatística & dados numéricos , Preservação de Órgãos , Alta do Paciente , Diálise Renal , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Resultado do Tratamento , Estados Unidos/epidemiologia , UrinaRESUMO
Purine nucleoside phosphorylase deficiency is an inherited disease of purine metabolism characterized clinically as combined immunodeficiency. The molecular defects have been published for 4 different alleles in 3 patients. We report four new mutations including two amino acid substitutions, A174P and G190V, a single codon deletion, delta I129, and a point mutation in intron 3 which leads to aberrant splicing and creation of a premature stop codon in exon 4 (286-18G-->A). Of the previously reported mutations, E89K was found in one additional patient, and R234P was found in 3 unrelated patients, making R234P the most common mutation reported to date in this disease.
Assuntos
Erros Inatos do Metabolismo/genética , Mutação/genética , Purina-Núcleosídeo Fosforilase/deficiência , Purina-Núcleosídeo Fosforilase/genética , Alelos , Éxons , Humanos , Íntrons , Reação em Cadeia da PolimeraseRESUMO
Transplantation of cultured postnatal human thymus was performed in a patient with complete DiGeorge syndrome. Biopsy of the graft 3 mo after implantation revealed normal CD1+ thymocytes in thymic cortical epithelial regions and CD1- thymocytes in thymic medullary epithelial regions, respectively. HLA analysis of graft thymocyte and thymic microenvironment components demonstrated that developing thymocytes and thymic macrophages were recipient derived, while thymic epithelial components were of donor origin. The patient, who initially had no T cells and had profoundly defective T cell function, developed normal T cell responses to mitogens and Ags, tolerance to donor in a mixed lymphocyte reaction, and normal Ab titers after tetanus toxoid and pneumovax immunization. Thus, transplantation of cultured postnatal human thymic tissue in humans can form functional chimeric thymic tissue, and may provide a strategy to reconstitute the peripheral T cell pool in select congenital and acquired immune deficiency syndromes.
Assuntos
Quimera/imunologia , Sobrevivência de Enxerto/imunologia , Timo/transplante , Síndrome de DiGeorge/terapia , Humanos , Lactente , Técnicas de Cultura de Órgãos , Timo/patologia , Transplante HomólogoRESUMO
In the United States, allocation of cadaveric kidneys is federally regulated and based on the concept of equal access to all patients, regardless of race, sex, age, or socioeconomic status. Nevertheless, it has been widely reported that African American patients with renal disease wait longer for kidney transplantation and, once transplanted, have poorer graft survival. We have assessed immunogenetic factors that may contribute to ethnic differences in allograft survival by examining the distributions of ABO blood groups, HLA antigens and haplotypes, percent reactive antibody (PRA), age, and gender in our local patient population. Approximately 62% of patients at our transplant center waiting for renal transplantation are African American; 39% are female. Age distribution is comparable to that reported nationally. ABO blood groups of patients on the waiting list are distributed similarly to those reported nationally for other renal patients. Sensitization to HLA antigens, through either blood transfusion, prior transplant, or pregnancy, has been strongly associated with poorer graft survival. Although, as expected, distribution of PRA was significantly different for males versus females at one time point, it did not differ between ethnic groups in our patient population. HLA polymorphism was assessed by comparisons of HLA allele and haplotype frequencies determined by analyses of African American and Caucasian families typed in our program since 1991. Haplotypes observed in each ethnic population were subjected to a variety of statistical analyses. Coefficient of contingency and Cramer's V statistic (measures of degree of association) were consistently higher for Caucasian haplotypes than for those of African Americans. Significantly more unique HLA haplotypes were observed among African American families than among Caucasian families. Thus, our data provide evidence for greater HLA linkage disequilibrium in Caucasians than in African Americans. HLA antigen and haplotype polymorphisms are likely, therefore, to be major immunogenetic factors contributing to ethnic differences in renal allograft survival.
Assuntos
População Negra/genética , Antígenos HLA/genética , Antígenos HLA/imunologia , Falência Renal Crônica/genética , Falência Renal Crônica/imunologia , População Branca/genética , Adolescente , Adulto , Distribuição por Idade , Feminino , Frequência do Gene , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Transplante de Rim/imunologia , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genéticaRESUMO
Nonhuman primates represent phylogenetic intermediates for studying the divergence of human and murine beta 2Ms. We report the nucleotide sequences of B2m cDNA clones from a baboon cell line, 26CB-1 (Papio hamadryas; primates: Cercopithecoidea), and a cotton-top tamarin cell line, 1605L (Saguinus oedipus; primates: Ceboidea). The baboon and tamarin B2m sequences indicate a very slow rate of B2m evolution in primates relative to that in murid rodents. Phenotypic evolution of beta 2M has also been very conservative in primates, with only 9-14 substitutions separating baboon or tamarin beta 2Ms from those of humans or orangutans. Analyses of silent and amino-acid-altering nucleotide substitutions provide evidence that negative selection has acted to limit variability in beta strands of primate beta 2Ms, while positive selection has promoted diversity in non-beta-strand regions of murine beta 2Ms. No evidence for the action of selection upon beta 2M residues that contact the class I heavy chain was found in primates or mice. The finding that different selective forces have operated upon primate and murine beta 2Ms suggests that beta 2M may have evolved to serve distinct functions in primates and mice.
Assuntos
Papio/genética , Saguinus/genética , Microglobulina beta-2/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Primatas/genética , Roedores/genéticaRESUMO
A simple, sensitive ELISA that is performed in 96-well microtiter plates and that requires less than 90 minutes to complete was developed for HLA-DRB oligotyping. The second exon of HLA-DRB1 was amplified using an unlabeled forward primer and a biotinylated reverse primer and the PCR product was immobilized in avidin-coated wells. Subsequent treatment included exposure to 0.4 N NaOH to remove the nonbiotinylated sense strand, addition of a fluorescein-labeled oligonucleotide probe, one or more 5-minute stringency washes, addition of an alkaline-phosphatase-labeled anti-FL FAB, and then alkaline-phosphatase substrate and amplifier. An intense red-violet color developed within 15 minutes in positive wells and could be quantitated by OD readings at 490-495 nm. To control for stringency and to establish threshold OD values for positive reactions, biotin-labeled antisense oligos that were complementary to the probe or that differed by one or more bases were immobilized in wells in place of PCR products. The assay was sensitive to < 0.05 pmol (approximately 4 ng)/well and required only standard incubators and waterbaths and an optional microplate reader. All reagents were commercially available. The method should facilitate oligotyping of both class I and class II alleles and is adaptable for analysis of other polymorphic gene products.
Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Antígenos HLA-DR/genética , Hibridização de Ácido Nucleico/métodos , Oligonucleotídeos/química , Sequência de Bases , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Reprodutibilidade dos TestesRESUMO
From May 1992 to March 1993, 50 infants with severe combined immunodeficiency (SCID) were given bone marrow transplants at Duke University Medical Center. None received chemotherapy for conditioning or for graft-versus-host disease (GVHD) prophylaxis. Forty-one received haploidentical parental marrow depleted of T cells by soybean lectin and sheep red blood cell resetting, and nine received HLA-identical marrow. Forty (80%) survived from 1 week to almost 11 years posttransplantation, including nine of nine (100%) HLA-identical marrow recipients and 31 of 41 haploidentical recipients. T-cell function was present within 2 weeks after transplantation of unfractionated HLA-identical marrow, but not until 3 to 4 months after T-cell-depleted haploidentical marrow stem cells. All 37 patients who are more than 4 months posttransplantation have good T-cell function, and all but one have 100% donor T cells. B-cell function developed slowly or not at all in some recipients of haploidentical marrow. Fourteen (four HLA-identical and 10 haploidentical recipients) have some donor B cells; 19 patients are receiving intravenous immune globulin (IVIG) therapy.
Assuntos
Haplótipos , Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa/terapia , Linfócitos B/imunologia , Transplante de Medula Óssea , Causas de Morte , Humanos , Imunodeficiência Combinada Severa/imunologia , Síndrome , Linfócitos T/imunologiaRESUMO
The HLA-A10 crossreacting group consists of the A25, A26, A34, A43 and A66 antigens. Here, we report allelic sequences for A43 and for 2 subtypes of both A26 and A34. Combining these results with previously determined sequences for A25, A26 and A66 enables molecular comparison of all the serologically defined A10 antigens. They form a closely related and well-defined group of alleles which may have originated with A*2601. Patterns of serological crossreactivity are correlated with sequence and a public epitope shared by A33 and members of the A10 family is localized to residues R62 and N63. The A*2501, A*4301 and A*6601 alleles appear to have derived from A*2601 by single gene conversion events with other HLA-A alleles. In the case of A*4301, the donor allele was probably an A29 allele as A*4301 has a small element of sequence in the alpha 1 helix (residues L62 and Q63) uniquely shared with A29. The chimaeric structure of A43 explains the reactivity of A43 molecules with both A10 and A29 alloantisera. The rare Oriental variant of A26 (A26v*) is encoded by an allele (A*2602) that differs from A*2601 by a unique nucleotide substitution which changes aspartate to asparagine at position 116 in the floor of the peptide binding groove. Thus A*2602 is a functionally distinct allele that originated by a point mutation. Alleles encoding A34 and A66 antigens are found to have very similar structures, explaining the difficulty in their serological definition.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Genes MHC Classe I , Antígenos HLA-A/genética , Isoanticorpos/imunologia , Alelos , Sequência de Aminoácidos , Sequência de Bases , Linhagem Celular Transformada , Sequência Consenso , Reações Cruzadas , Variação Genética , Antígenos HLA-A/imunologia , Teste de Histocompatibilidade , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido NucleicoRESUMO
Previous analysis has emphasized the correlation between primary structures of class I HLA molecules and their patterns of serologic cross-reactivity. Here we describe the structures of two serologic groups of HLA-B alleles for which this is not the case. HLA-B45, an allele associated with black populations, is serologically paired with B44 in the B12 group; its structure, however, is divergent from that of B44 but closely related to B50. The BN21 (B*4005) allele is associated with native Americans and is serologically grouped with B50 in the B21 group; its structure, however, is more closely related to alleles of the B40 group. The B44 and B45 serologically cross-reactive molecules differ at seven functional positions of the Ag recognition site; the B50 and BN21 molecules differ at four such residues. These differences are predicted to alter peptide presentation and be capable of eliciting strong alloreactive T cell responses. For these pairs of B12 and B21 Ag, serology appears dominated by epitopes formed by short sequences of the alpha 2 helix which have been shuffled by recombination between alleles. The implications of these results for HLA matching in transplantation are discussed.
Assuntos
Antígenos HLA-B/imunologia , Alelos , Sequência de Aminoácidos , Reações Cruzadas , Epitopos , Antígenos HLA-B/genética , Humanos , Dados de Sequência Molecular , Polimorfismo Genético , Estrutura Secundária de Proteína , Grupos Raciais , Alinhamento de SequênciaRESUMO
Alleles encoding five HLA-A and B Ag characteristic of black populations have been isolated and their nucleotide sequences determined. In each case, the "black" allele is similar to a "related" allele found in caucasoid populations. The primary differences between these pairs of alleles are localized clusters of nucleotide substitutions that change two to five residues of the Ag recognition site. The pattern of differences indicates that the pairs of black and caucasoid alleles diverged primarily as a result of interallelic conversion events.
Assuntos
Alelos , População Negra/genética , Conversão Gênica , Antígenos HLA-A/genética , Antígenos HLA-B/genética , África , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Estados Unidos , População Branca/genéticaRESUMO
HLA haplotypes containing the HLA-B46 allele react with both anti-Cw1 and anti-Cw3 alloantisera, a pattern of reactivity defined as the Cw11 antigen and postulated to involve either a distinctive Cw11 allele or a duplicated HLA-C locus. From serological characterization of CIR cells transfected with B46 cDNA we now demonstrate that the anti-Cw3 reactivity with these haplotypes is solely due to the B46 molecule and not to an HLA-C molecule. Furthermore, isolation and characterization of HLA-C mRNA from cells expressing B46 strongly suggest that anti-Cw1 reactions are directed against the product of a conventional Cw1 allele. The antigenic cross-reactivities of B46 with B62 and Cw3 correlate with its chimaeric primary structure, which is identical to that of B62, except in the alpha 1 helix where it is identical to both Cw3 and Cw1. The structure, distribution and genetic linkage of B46 indicate it is of recent, Asian origin and is the result of a gene conversion, involving Cw1 as the donor gene and B62 as the recipient. These results demonstrate that the Cw11 antigen neither corresponds to a novel HLA-C allele nor a duplicated HLA-C locus, but to a combination of epitopes contributed by linked Cw1 and B46 alleles. The nucleotide sequence we previously and erroneously attributed to a distinct Cw11 allele is now demonstrated to encode Cw8. Isolation of the cDNA clone with this sequence from a library made from a cell homozygous for the B46 haplotype was probably an artefact of contamination.
Assuntos
Reações Antígeno-Anticorpo/genética , Artefatos , DNA/isolamento & purificação , Genes MHC da Classe II , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Isoanticorpos/imunologia , Alelos , Sequência de Aminoácidos , Sequência de Bases , Sequência Consenso , Reações Cruzadas , Epitopos/genética , Epitopos/imunologia , Haplótipos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Polimorfismo Genético , Conformação Proteica , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , Terminologia como AssuntoRESUMO
Differential DNA heteroduplex patterns were used to investigate inheritance of HLA class II region genes in a family where a living related kidney transplant was under consideration. Serologic typing of the family members for HLA class I (HLA-A, B, and C) and class II (HLA-DR and DQ) alleles indicated that the patient (109) and one sibling (126) had inherited the same maternal and paternal HLA alleles. However, a strong reciprocal mixed lymphocyte response implied that these two individuals were not completely HLA identical. Serologic typing for HLA-DQ was confirmed by allele-specific oligonucleotide typing family members for HLA-DQ alpha and beta genes. To assess a possible nonidentical gene(s), DNA was amplified from all family members at the second exon of the DR beta, DQ alpha, DP alpha, and DP beta genes and the products were analyzed by DNA heteroduplex formation. This method showed that individuals 109 and 126 were identical at DR and DQ but differed at DP. This difference was confirmed by allele-specific oligonucleotide hybridization and indicated that 126 had inherited a recombinant maternal chromosome with a cross-over occurring in the region between the DQ beta and DP alpha genes. These data demonstrate the applicability of DNA heteroduplex patterns in establishing identity-nonidentity of alleles in the major histocompatibility complex.
Assuntos
Genes MHC da Classe II/genética , Antígenos HLA-D/genética , Ácidos Nucleicos Heteroduplexes/genética , Recombinação Genética/genética , Sequência de Bases , Feminino , Humanos , Teste de Cultura Mista de Linfócitos , Masculino , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/genética , LinhagemRESUMO
Structural characteristics of major histocompatibility complex class I antigens associated with natural killer (NK)-resistance phenomena were examined. Previous research has shown that transfection of class I genomic DNA clones into class I-deficient, NK-sensitive target cell lines results in transfectants exhibiting class I+, NK-resistant phenotypes. In contrast to the HLA-A3, -B7, -B27, and -Bw58 class I molecules, the HLA-A2 class I molecules were shown not to protect target cells from NK activity. Here we show that this nonprotective phenotype maps to the alpha 1 domain of the HLA-A2 molecule by examining the NK-protective capacity of the natural interdomain recombinant HLA-Aw69 molecule. HLA-Aw69, which consists of an alpha 1 domain exhibiting homology with HLA-Aw68, and alpha 2/alpha 3/transmembrane-cytoplasmic domains, exhibiting homologies with HLA-A2, mimics HLA-Aw68 and provides HLA-A,B null target cell (C1R) transfectants with increased resistance to NK. Further, the inability of transfected HLA-A2 to confer protection against NK activity can be completely attributed to the expression of a "nonpermissive" residue at position 74 in the alpha 1 domain. Site-directed mutation of the His-74 residue in HLA-A2 to the Asp-74 (HLA-A3, -Aw68, -Aw69, -B7) residue generates a mutant that provides C1R cell line transfectants an NK-resistant phenotype. As His-74 blocks access to a side pocket in the HLA-A2 antigen-binding cleft, these results support the critical involvement of residues within the peptide-binding groove of class I molecules in determining the NK susceptibility phenotype of class I+ target cells.
Assuntos
Citotoxicidade Imunológica , Antígeno HLA-A2/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Alelos , Anticorpos Monoclonais , Linhagem Celular , Clonagem Molecular , Imunofluorescência , Antígeno HLA-A2/genética , Antígenos de Histocompatibilidade Classe I/genética , Teste de Histocompatibilidade , Humanos , Masculino , Mutagênese Sítio-Dirigida , Fenótipo , Plasmídeos , Radioimunoensaio , TransfecçãoRESUMO
Dermatitis herpetiformis (DH) is characterized in part by an associated gluten-sensitive enteropathy (GSE), and a strong association with the HLA antigens HLA-A1, -B8, -DR3, and -DQw2, essentially identical to that seen in patients with isolated GSE (celiac disease). A 4.0-kb RsaI RFLP has been identified using a DQ beta-chain cDNA and localized to the HLA-DP beta-chain region. This RFLP has been found more frequently in patients with isolated GSE than in normal HLA matched controls. We have analyzed genomic DNA from 24 patients with DH and 15 HLA-matched controls to determine if this 4.0-kb RsaI RFLP was present in patients with DH. Twenty-one of 24 (87%) of patients with DH were found to have this RFLP as compared to 7 of 10 (70%) HLA-DR3, -DQw2 matched control subjects (p = 0.23). Thus, the 4.0-kb RsaI RFLP detected in patients with isolated GSE is also present in patients with DH; however, its frequency in DH patients does not differ significantly from that of HLA matched controls. Family studies of patients with DH revealed that although the 4.0-kb RsaI RFLP segregated with the HLA-A1, -B8, -DR3, -DQw2 haplotype in one family, it did not segregate with this disease-associated haplotype in two other families. In both patient and control populations, this RFLP was associated with HLA-DPw1 or -DPw3 phenotypes; 25 of 26 (96%) HLA-DPw1 or -DPw3 subjects were found to have this RFLP compared to only 1 of 6 (17%) who did not express HLA-DPw1 or -DPw3 (pc = 0.0009). These population and family data suggest that this 4.0-kb RsaI RFLP is primarily associated with the HLA-DPw1, -DPw3 phenotype, rather than the clinical manifestations of DH. These data further document that the strongest association of DH with HLA antigens remains with HLA-DQw2 and HLA-DR3 antigens.