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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)

Major histocompatibility complex-determined antigens were originally identified as a consequence of their ability to induce rejection of tissue grafts between organisms that are not genetically identical. Currently, much is known about their biochemical nature and intended biological functions. Major histocompatibility complex antigens are found on three types of glycoprotein molecules. One type (class I) is associated with beta 2-microglobulin in the cell-surface membranes of all body tissues and includes H-2K and D molecules in mice and HLA-A, B, and C molecules in humans. These antigens are the major cause of rejection of transplanted organs. The other two types of glycoproteins (class II) are noncovalently linked to each other, are found in the cell-surface membranes of a limited number of cell types, and include H-2-Ia molecules in mice and HLA-DR molecules in humans. They are noted for their ability to elicit graft-versus-host disease. Both class I and class II molecules are, however, important for the immune recognition of pathogens, although the types of responses they modulate are different. Class I molecules are important in the recognition of cell-surface antigens, whereas class II molecules control responsiveness to soluble antigens. Major histcompatibility complex-encoded molecules are also involved in certain autoimmune diseases. As our understanding of major histocompatibility complex-controlled immune responsiveness broadens and hybridoma and gene-cloning technology advances, specific enhancement of desired immune responses and suppression of deleterious ones will most likely become possible.
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PMID:Immune-response gene-associated antigens (Ia/DR). Structure and function in immunologically related diseases. 640 18

Complete hemopoietic takeover between semiallogeneic adults can be accomplished by the administration of antihost major histocompatibility complex (MHC) monoclonal antibody (mAb) and donor stem cells. The recipients of such treatment are termed antibody-facilitated chimeras, and they have been produced in (BALB/cCr----(BALB/cCr X C3H/HeJ)F1 and DBA/2J----(DBA/2J X C3H/HeJ)F1 strain combinations. Donor stem cells can be derived from spleen, bone marrow, or T-cell-depleted bone marrow. Engraftment by donor hemopoietic cells can be facilitated by mAbs directed toward class I (anti-H-2Kk) or class II (anti-H-2I-Ak) MHC antigens of the host. By monitoring isozymes of glucose phosphate isomerase, it can be shown that the establishment of donor hemopoiesis is stable, persisting for more than a year without graft-versus-host disease. The effect of anti-MHC mAb on pluripotential stem cells was evaluated by the (colony-forming units-spleen) (CFU-S) assay. The number of CFU-S in target (H-2k) bone marrow was reduced by in vitro pretreatment with anti-H-2Kk mAb, but not with anti-H-2I-Ak mAb. In contrast, in vivo administration of either anti-H-2Kk or anti-H-2I-Ak mAb resulted in a marked decrease in the CFU-S capacity of relevant strain mice. These observations suggest that the target of the in vivo mAb treatment may be pluripotential stem cells--or perhaps the hemopoietic microenvironment.
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PMID:Antibody-facilitated chimeras. Stem cell allotransplantation using antihost major histocompatibility complex monoclonal antibodies instead of lethal irradiation for host conditioning. 646 66

Noninbred rabbits that were characterized for antigens of the major histocompatibility complex (MHC) by serological (RLA) typing were used as adult donors and newborn recipients of lymphoid cells. The majority of RLA-heterozygous (CE) animals transplanted with homozygous type C cells died before 7 weeks of age with clinical and histological signs of graft-versus-host disease, but a small proportion survived with their lymphoid and erythroid systems completely converted to phenotypes of the donors. Takeover of the host's hematopoietic system was associated with a transient hyperimmunoglobulinemia, mostly of donor origin, and with a striking and permanent abrogation of allotype suppression on the part of donor lymphocytes. In contrast, as shown in this and in earlier publications, recipients of RLA-compatible cells become stable B lymphocyte chimeras without detectable T cells or erythrocytes of donor type. In the latter case allotype suppression is neither established in the recipient nor abrogated in the donor's cells.
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PMID:Graft-versus-host reactions and abrogation of allotype suppression following histoincompatible lymphoid cell transfers in rabbits. 661 Feb 34

The immunogenicity of cell surface markers associated with specific anti-major histocompatibility complex (MHC) alloreactivity of rat peripheral T lymphocyte subpopulations has been demonstrated in the past by the ability of such cell populations to induce a profound and specific resistance to systemic graft-vs.-host (GVH) disease in adult rats. Our studies demonstrate that these specificity-associated anti-MHC parental strain T cell markers are also tolerogenic; if small numbers of parental strain T cells are administered to newborn F1 rats, they result in the specific inability to induce GVH resistance later on in adult life. Moreover, unlike normal animals, these F1 rats are extremely sensitive to systemic GVH disease caused by T cells from the original donor parental strain.
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PMID:Induced tolerance in F1 rats to anti-major histocompatibility complex receptors on parental T cells. Implications for self tolerance. 697 3

Bone marrow transplants with low marrow cell doses (less than or equal to 4 x 10(8) cells/kg) from unrelated donors were carried out in 16 dogs conditioned with 9 Gy (900 rad) of total body irradiation. No immunosuppression was given after grafting. Eleven donor-recipient pairs were phenotypically identical (group 1) for the known antigens of the canine major histocompatibility complex (DLA) and in five the donor was homozygous and the recipient heterozygous for DLA (group 2), as determined by serological histocompatibility typing and mixed leukocyte cultures including homozygous cell typing. In addition, lymphocytes from donors and recipients in group 1 were mutually nonreactive in cell-mediated lympholysis; lymphocytes from recipients in group 2 were not cytotoxic against donor cells. Eight dogs rejected their grafts and eight showed sustained engraftment; of these, four died from graft-versus-host disease. The incidence of rejection was higher than in DLA-identical littermates but lower than in DLA-nonidentical unrelated or littermate dogs. These results indicate that antigens different from the recognized alleles at DLA are involved in the control of engraftment. These antigens most likely represent the expression of unrecognized differences within DLA or are coded for by a locus different from but linked to DLA-A, B, C or D; they are not recognized in the cell-mediated lympholysis assay.
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PMID:Marrow grafts between phenotypically DLA-identical and haploidentical unrelated dogs: additional antigens controlling engraftment are not detected by cell-mediated lympholysis. 703 18

Four hundred and ten heterotopic spleen transplants were performed in inbred guinea pigs of strains 2 and 13 whose major histocompatibility complex differs only in the I region and which rapidly reject reciprocal skin allografts. Spleen allografts from strain 13 to strain 2 survived throughout the lifetime of the hosts, whereas spleen allografts from strain 2 to strain 13 were rejected within 3 weeks. Animals not rejecting their spleen transplants were specifically tolerant of donor strain skin allografts. Strain 2 recipients of strain 13 spleen grafts had a surprising high mortality from graft-versus-host disease which peaked at 6 weeks after transplantation.
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PMID:Induction of transplantation tolerance in guinea pigs by spleen allografts. I. Operative techniques and clinical results. 703 23

Graft-versus-host disease (GvHD) after bone-marrow transplantation in dogs is controlled by many different genetic systems. In littermate combinations identical for the major histocompatibility complex (MHC) the number of systems that influence GvHD is related to the number of donor lymphocytes injected. If the number of donor lymphocytes administered is sufficiently low, minor histocompatibility systems do not influence survival after bone-marrow transplantation. With increasing numbers of donor lymphocytes the beneficial influence of MHC matching on GvH incidence and severity disappears and minor histocompatibility antigens, coded for on at least two other autosomal chromosomes as well as possibly the Y chromosome, can cause severe GvHD. In contrast, the X chromosome does not appear to carry a histocompatibility system that is of relevance to GvHD control. The severity and tissue distribution of histological signs of GvHD in recipients of bone-marrow and lymph-node cells from MHC-identical donors are similar to those in recipients of MHC-mismatched bone-marrow cells. Female donors do appear to cause severe GvHD more frequently than males. In contrast to rhesus monkey and human bone-marrow cells, dog bone-marrow cells are negative in PHA tests. This is in accordance with the generally benign course of GvHD in dogs that are treated with bone-marrow cells only from histocompatible littermate donors. The influence of the sex of the bone-marrow donor on GvHD incidence and severity is not reflected in differences between PHA tests with male and female dog lymphocytes. A better predictive test for GvH potential than the PHA test appears to be needed. Alternatives to additional donor selection for the prevention of GvHD in histocompatible recipients appear to be the use of a male donor and the removal of lymphocytes from bone-marrow-cell suspensions prior to transplantation.
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PMID:Alternatives to donor matching for control of graft-versus-host disease. 704 63

Graft-versus-host disease (GVHD) caused by T-cell recognition of minor histocompatibility (MiHC) antigens is a major complication of bone marrow transplantation. GVHD therapy has focused on removal or suppression of donor T cells, but modulation of MiHC antigen presentation to CD4+ T cells may represent an alternative approach. Chloroquine is known to inhibit major histocompatibility complex (MHC) class II presentation of antigen in vitro by affecting invariant chain dissociation from MHC class II. The goal of this study was to evaluate the role of chloroquine in abrogating T-cell priming to MiHC and GVHD in mice after transplantation of an MiHC incompatible donor. C57BL/6 mice were treated with phosphate-buffered saline or chloroquine at 400 micrograms intraperitoneally every day for 5 days before priming with BALB.B cells (MiHC-incompatible) followed by weekly injections of chloroquine at 400 micrograms for 4 to 8 weeks. Chloroquine treatment decreased the proliferative T-cell response to MiHC by 67% and the cytolytic T-cell activation by greater than 50%. After bone marrow transplantation (LP/J into C57BL/6; MiHC-incompatible), GVHD was significantly decreased in chloroquine-treated mice (17% with GVHD) as compared with that in controls (92% with GVHD). Chloroquine treatment did not have other effects in vivo on the normal T- and B-cell mitogenic responses, T-cell allogeneic responses, and MHC class II and I surface expression. Chloroquine treatment does decrease the ability of C57BL/6 antigen-presenting cells to stimulate C3H.SW T cells reactive with MiHC expressed on C57BL/6 cells, suggesting an effect on MHC class II presentation of MiHC in vivo. Treatment with chloroquine in vivo appears to result in decreased CD4+ T-cell priming to MiHC and GVHD by decreased class II MHC antigen presentation. Thus, chloroquine treatment may represent an alternative approach to control GVHD.
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PMID:Chloroquine treatment affects T-cell priming to minor histocompatibility antigens and graft-versus-host disease. 749 96

Costimulatory signals are absolutely required for T-cell activation after T-cell receptor/major histocompatibility complex-peptide interaction. So far, the best-known candidate essential costimulatory signal is mediated by interaction of CD28 on T cells with B7 on antigen-presenting cells. Using an allogeneic B7+ Epstein-Barr virus-transformed B-cell line as stimulator, we found that addition of a monoclonal antibody (MoAb) to B7 that efficiently blocks B7-CD28 interaction only partially inhibited proliferation and interleukin-2 (IL-2) production in primary and secondary mixed lymphocyte reactions (MLR), whereas the generation of cytotoxic T lymphocytes (CTL) was not affected. Inhibition of primary or secondary MLR-induced T-cell activation with cyclosporin A (CsA) at nontoxic concentrations also was never complete. However, the combination of CsA and anti-B7 MoAb B7-24 synergistically blocked allogeneic B cell-induced T-cell proliferation, IL-2 production, and CTL generation. These data suggest that the mere blockage of B7-CD28 interaction during allotransplantation will be insufficient to prevent rejection or graft-versus-host disease. However, low CsA concentrations, when combined with an agent blocking B7-CD28 interaction, can potentially achieve complete immunosuppression.
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PMID:Synergy between cyclosporin A and a monoclonal antibody to B7 in blocking alloantigen-induced T-cell activation. 750 79

The phenomenon of T cell allorecognition is difficult to accommodate within the framework of a T cell repertoire positively selected in the thymus, unless allorecognition results from the cross-reactions of self-major histocompatibility complex restricted T cells. Herein, we demonstrate the dual specificity of cytotoxic T lymphocyte (CTL) clones for the immunodominant Epstein-Barr virus (EBV) epitope FLRGRAYGL, presented on HLA-B8, and the alloantigen HLA-B*4402. CTL which recognized peptide FLRGRAYGL in association with HLA-B8 could be reactivated in vitro from healthy individuals who had been exposed previously to EBV, using stimulator cells expressing the cross-reacting alloantigen HLA-B*4402. Limiting dilution analysis of the alloresponse to HLA-B*4402 in eight healthy individuals revealed that HLA-B8+, EBV-sero+ donors had higher CTL precursor frequencies for alloantigen HLA-B*4402 than EBV-sero- control donors. It is surprising that the majority (65-100%) of anti-HLA-B*4402 CTL, generated in limiting dilution mixed lymphocyte reactions between responder cells from HLA-B8+, EBV-sero+ individuals and HLA-B*4402+ stimulators, also recognized the EBV CTL epitope FLRGRAYGL/HLA-B8. In contrast to previous studies showing extensive diversity in the T cell repertoire against individual alloantigens, these data demonstrate that the response to an alloantigen can be dominated by CTL cross-reactive with a single viral epitope, thus illustrating a possible mechanism for the frequent clinical association between herpesvirus exposure and graft-versus-host disease after bone marrow transplants.
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PMID:An alloresponse in humans is dominated by cytotoxic T lymphocytes (CTL) cross-reactive with a single Epstein-Barr virus CTL epitope: implications for graft-versus-host disease. 751 82


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