Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018133 (graft-versus-host disease)
 18,032 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The male-specific minor histocompatibility antigen H-Y plays an important role in both graft rejection and graft-versus-host disease following transplantation of male tissue into females that are completely matched at the major histocompatibility loci. The recent identification of two peptides that, in association with the mouse H-2Kk or human HLA B7 major histocompatibility class I molecules, are recognised by H-Y-specific T cells, has provided evidence for the molecular basis for such anti-H-Y responses. These peptides are encoded by the mouse and human homologues of a ubiquitously expressed Y chromosome gene, Smcy, whilst the equivalent peptides encoded by the X chromosome homologues of this gene fail to be recognised. Genetic studies have demonstrated that, as is the case for other minor histocompatibility antigens, peptide epitopes from several closely linked genes may be required to interact in order to elicit a response against H-Y. Definition of the peptides and the genes that encode these epitopes will allow the development of tolerogenic protocols that could specifically down-modulate the response to H-Y and perhaps even other minor histocompatibility antigens.
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PMID:Why do some females reject males? The molecular basis for male-specific graft rejection. 908 28

The presence of recipient disparity for a minor histocompatibility antigen termed HA-1 is associated with an increased risk of grades II-IV GVHD after marrow transplantation from an HLA-identical sibling. These data offer an opportunity to test the validity of theoretical models suggesting that the minor antigens capable of eliciting GVHD in any given individual are encoded by approximately seven genetic loci. Published data and theoretical models agree that there is little benefit to be gained by typing and matching at a single locus. The models predict, however, that substantial benefit would be possible if multiple loci could be typed. The success of matching would be enhanced by the availability of assays that would allow typing for at least four of the loci encoding antigens that could cause GVHD in any given individual.
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PMID:How much benefit can be expected from matching for minor antigens in allogeneic marrow transplantation? 924 10

Interest in the complexity of the HLA system and its relevance in the selection of unrelated bone marrow donors has had an important impact on our understanding of the immunogenetics of HLA and non-HLA or minor histocompatibility systems. More than 50 genes on the short arm of chromosome 6, which carries the information for HLA, have been identified and there are more to come. HLA-class I and HLA-class II each have more than 200 alleles, and the number is growing. The HLA-C antigens appear to act as targets for natural killer cells. New inroads have been made in the recognition of the minor histocompatibility antigens HA-1 to -5, which can be recognized by cytotoxic T-cell clones and are inherited in a Mendelian fashion. A mismatch for HA-1 might lead to graft-versus-host disease. The introduction of new technologies, especially polymerase chain reaction, has been immensely helpful in mapping the genetic complexity of HLA. Methodology now allows typing for HLA on the level of DNA in a matter of a few hours and is most useful when selecting a suitable bone marrow donor. The new genetic information available makes it clear that many so-called HLA matched unrelated bone marrow transplants performed in the past were actually mismatched. Nevertheless, many of them had a good clinical outcome. It is clear that one of the most important challenges is to determine which mismatched transplants will fare well and which should be avoided. Recent findings in organ transplantation might be helpful here.
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PMID:Immunogenetics. 937 18

The minor histocompatibility antigen (mHag) HA-1 is the only known mHag for which mismatching is correlated with the development of severe graft versus host disease (GvHD) after human leukocyte antigen-identical bone marrow transplantation. HA-1 was found to be a nonapeptide derived from an allele of the KIAA0223 gene. The HA-1-negative allelic counterpart encoded by KIAA0223 had one amino acid difference from HA-1. Family analysis with HA-1 allele-specific polymerase chain reaction showed an exact correlation between this allelic polymorphism and the HA-1 phenotype. HA-1 allele typing of donor and recipient should improve donor selection and allow the determination of bone marrow transplantation recipients with high risk for HA-1-induced GvHD development.
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PMID:The minor histocompatibility antigen HA-1: a diallelic gene with a single amino acid polymorphism. 946 41

Recipient mismatching for the minor histocompatibility antigen HA-1 has been associated with acute graft-versus-host disease after allogeneic marrow transplantation. Two polymorphic nucleotides near an exon-intron junction of the gene encoding this minor histocompatibility antigen have been identified. In this study, we determined the genomic DNA sequence of the intron downstream from this polymorphic exon. Based on this sequence, primers were designed to amplify the genomic HA-1 gene sequence, and analysis of restriction fragment length polymorphisms was used to assign the HA-1 genotypes of 160 unrelated probands and a paired sibling for each proband. Among probands, the HA-1H allele frequency was 0.441, and the HA-1R allele frequency was 0.559. The distribution of HA-1 genotypes showed close fit with Hardy-Weinberg equilibrium. Likewise, the number of sibling pairs with disparity for HA-1 alleles showed close fit with predictions based on Hardy-Weinberg equilibrium. These results provide a simple and well validated method for future studies correlating HA-1 disparity with clinical outcome after allogeneic marrow transplantation.
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PMID:Definition of the gene encoding the minor histocompatibility antigen HA-1 and typing for HA-1 from genomic DNA. 982 May 94

Graft-versus-host disease (GvHD) can be a major complication of allogeneic bone marrow transplantation even in recipients of HLA genotype-identical transplants. Disparities in minor histocompatibility antigens (mHags) between donor and recipient are a potential risk for the development of GvHD. A mismatch for the mHag HA-1 can cause GvHD in adult recipients of allogeneic bone marrow from HLA-identical donors. The mHag HA-1, first identified by HLA-A*0201-restricted cytotoxic T cells (CTLs), was recently chemically characterized as a nonapeptide. On the cDNA level, the HA-1 locus has two alleles, HA-1H and HA-1R, which differ in two nucleotides, resulting in a single amino acid substitution. Here we report on the genomic structure of the HA-1 locus. Isolation and sequencing of cosmid DNA encoding the HA-1 peptide sequence revealed that the HA-1 alleles are encoded by two exons. Two different primer sets were designed, each consisting of allele-specific primers and a common primer, and both sets containing intronic sequences. We performed genomic DNA typing of three families consisting of 24 HLA-A*0201-positive individuals. The predicted allele-specific products correlated in all cases with the mHag classification by CTLs and by RT-PCR. We demonstrate for the first time the genomic identification of the mHag HA-1 locus. Prospective genomic typing for the HA-1 alleles will improve donor selection and identify HLA-A*0201-positive recipients with a high risk for HA-1-induced GvHD.
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PMID:Genomic identification of the minor histocompatibility antigen HA-1 locus by allele-specific PCR. 982 May 94

To study sensitisation to minor histocompatibility antigens (mHag) before and after BMT, we measured antidonor CTL activity in five patients who had rejected their graft, and in a control group of 10 leukemic patients who engrafted without complications. All patients were transplanted with marrow from an HLA-identical sibling. Fourteen patients were conditioned with cyclophosphamide (120 mg/kg) and TBI (1350 cGy) and received a T cell-depleted graft, while one patient with aplastic anaemia received cyclophosphamide alone and unmanipulated marrow. Before transplantation, anti-donor CTL activity was detected in two of the 15 patients. These patients rejected their grafts at days 21 and 58, respectively. In the other three patients who rejected their grafts at days 41, 60 and 250, CTL activity was found only after transplantation. In contrast, no anti-donor CTLs could be detected at any time in the 10 patients who engrafted permanently. We have identified some of the mHags recognised during graft rejection by cloning and subsequent specificity analysis of the recipient CTLs. In the patient who rejected at day 41 without detectable immunisation before BMT, the response was directed against HA-1, a minor antigen known to play a role in GVHD. In the other combinations, a significant part of the CTL activity was directed against the male antigen H-Y. In the patient who rejected the marrow of her HLA-identical brother at day 250, two clones recognised H-Y, while five others recognised at least three distinct autosomal mHags. This patient had an HLA-identical sister who expressed only one autosomal mHag that had been recognised by one single T cell clone. After re-transplantation with the marrow of this second donor, the CTL activity could no longer be detected and the patient engrafted without further complications.
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PMID:Clinical consequences of sensitisation to minor histocompatibility antigens before allogeneic bone marrow transplantation. 982 18

Allogeneic bone marrow transplantation (BMT) is a common treatment of hematologic malignancies. Recurrence of the underlying malignancy is a major cause of treatment failure. Donor-derived cytotoxic T lymphocytes (CTLs) specific for patients' minor histocompatibility antigens (mHags) play an important role in both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) reactivities. mHags HA-1 and HA-2 induce HLA-A*0201-restricted CTLs in vivo and are exclusively expressed on hematopoietic cells, including leukemic cells and leukemic precursors, but not on fibroblasts, keratinocytes, or liver cells. The chemical nature of the mHags HA-1 and HA-2 is known. We investigated the feasibility of ex vivo generation of mHag HA-1- and HA-2-specific CTLs from unprimed mHag HA-1- and/or HA-2-negative healthy blood donors. HA-1 and HA-2 synthetic peptide-pulsed dendritic cells (DCs) were used as antigen-presenting cells (APC) to stimulate autologous unprimed CD8(+) T cells. The ex vivo-generated HA-1- and HA-2-specific CTLs efficiently lyse leukemic cells derived from acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL) patients. No lytic reactivity was detected against nonhematopoietic cells. Sufficient numbers of the CTLs can be obtained for the adoptive immunotherapy purposes. In conclusion, we present a feasible, novel therapy for the treatment for relapsed leukemia after BMT with a low risk of GVHD.
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PMID:Feasibility of immunotherapy of relapsed leukemia with ex vivo-generated cytotoxic T lymphocytes specific for hematopoietic system-restricted minor histocompatibility antigens. 1063 95

Allogeneic bone marrow transplantation (BMT) can be accompanied by a beneficial T cell-mediated antitumor immune response known as graft-versus-tumor (GVT) activity. However, BMT donor T cells are not exposed to target antigens of GVT activity until transfer to the host, where tumor antigen presentation may be suboptimal. This study tested in a murine model the hypothesis that immunization of MHC-matched allogeneic donors with a recipient-derived tumor cell vaccine would substantially increase GVT activity and extend survival of BMT recipients with preexisting micrometastatic tumor. C3H.SW and C57BL/10 mice were immunized against a C57BL/6-derived fibrosarcoma or leukemia, and they were used as BMT donors. Recipients were H-2-matched, minor histocompatibility antigen-mismatched C57BL/6 mice with previously established micrometastatic tumors. Donor immunization led to a significant increase in GVT activity that was T cell dependent and cell dose dependent. In some settings, donor immunization also prolonged survival of recipients with preexisting micrometastatic tumors. However, donor immunization significantly increased the incidence of fatal graft-versus-host disease such that long-term survival was uncommon. In vitro cytotoxicity assays indicated that donor immunization induced both tumor-selective and alloreactive cytolytic T-cell populations. In vivo cross-protection assays showed that a substantial portion of the GVT effect was mediated by alloreactive cells not specific for the immunizing tumor. In conclusion, immunization of allogeneic BMT donors with a recipient-derived whole tumor cell vaccine substantially increases GVT activity but also exacerbates graft-versus-host disease.
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PMID:Enhancement of graft-versus-tumor activity and graft-versus-host disease by pretransplant immunization of allogeneic bone marrow donors with a recipient-derived tumor cell vaccine. 1019 24

Despite contemporary typing procedures for bone marrow transplantation (BMT), graft-versus-host disease (GVHD) continues to be a major complication of transplants performed between MHC-matched donors and recipients. Although GVHD can be alleviated by T cell depletion, this procedure increases the risk of graft failure and leukemic relapse and therefore is not a solution to the GVHD problem. The high degree of variation in the intensity of GVHD observed in different patients suggests that multiple non-MHC genetic factors influence GVHD severity. We hypothesize that, in addition to minor histocompatibility antigen disparities, polymorphisms in genes encoding immunologic effector molecules may be important factors influencing GVHD development. This study aims to explore this hypothesis by identifying non-MHC genes that influence the outcome of BMT in a murine model. In this model, B10.D2 donor leukocytes cause acute GVHD in (C57BL/6xDBA/2)F1 (B6D2F1) recipients, whereas DBA/2 donor leukocytes do not. To date, a locus on chromosome 1 has been identified as influencing the severity of GVHD in this model. Our current study shows that a locus on chromosome 2 acts independently of the chromosome 1 locus to also influence GVHD severity in this model. The region of chromosome 2 implicated in our study contains genes encoding beta2-microglobulin, the minor histocompatibility antigen H-3 and the pro-inflammatory cytokine IL-1.
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PMID:A locus on chromosome 2 influences the development of acute graft-versus-host disease in a murine model. 1038 59


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