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)

Induction of a graft-versus-host (GVH) reaction (GVHR) in non-irradiated (C57BL/10ScSn x DBA/2)F1 mice (BDF1) with DBA/2 lymphoid cells leads to chronic GVH disease (GVHD). One of the pathological alterations of this type of GVHD is hyperplasia of host B cells with production of lupus-like autoantibodies. This hyperstimulation of host B cells has previously been demonstrated to be induced by alloreactive donor T helper cells that were also proposed to maintain it. We provide three pieces of experimental evidence in support of this concept. First, treatment of mice with chronic GVHD by injection of monoclonal anti-Thy-1.2 antibodies, performed at week 6 after the injection of C57BL/6 lymphoid cells into (C57BL/6 x C57BL.bm12)F1 mice led to a significant decrease in the titre of anti-nuclear antibodies. Second, CD4+ donor T cells persisted in BDF1 mice with GVHD (GVHF1) for at least 10 weeks after the induction of GVHR; these T cells showed alloreactive helper activity against H-2b MHC determinants of the opposite parent in vitro. Third, T cells of GVHF1 mice, obtained 2 months after the induction of GVHR and transferred into normal secondary recipients, induced signs of chronic GVHD in DBF1 but not in DBA/2 mice. The combined results show that persisting donor T helper cells in GVHF1 mice retain their alloreactivity towards H-2 class II antigens for a long time after the induction of GVHR and they strongly suggest that these T cells are also the driving force behind the production of lupus-like autoantibodies at the late stage of chronic GVHD.
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PMID:Persistence of allospecific helper T cells is required for maintaining autoantibody formation in lupus-like graft-versus-host disease. 214 86

Epa-1 is a tissue-restricted, non-major histocompatibility (MHC) antigen that may be responsible for the extreme sensitivity of skin to allograft rejection and graft-versus-host disease (GVHD), especially with MHC-compatible donors and recipients. To confirm that Epa-1 serves as a target in allograft rejection and GVHD, we isolated Epa-1-specific cytotoxic T lymphocyte (CTL) clones completely in vivo from sponge-matrix allografts and from lymph nodes draining rejecting skin allografts. These clones induced GVHD-like skin lesions in antigen-specific, MHC-restricted fashion following intradermal inoculation into appropriate hosts. The in vivo-derived clones are conventional CTL since they are IL-2-dependent and express the Thy-1.2+, Lyt-1-, Lyt-2+, L3T4- phenotype. The results of this study also are pertinent to the controversy over which T-cell subset actually mediates allograft immunity, since the intragraft isolation and subsequent cloning of conventional CTL that induce necrotizing skin lesions are direct evidence that CTL are the proximal mediators of allograft rejection.
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PMID:In vitro and in vivo cytotoxicity of T cells cloned from rejecting allografts. 242 46

Injection of B10.D2 cells into irradiated H-2d compatible (DBA/2xB10.D2)F1 recipients provokes a lethal GVH that can be abrogated by donor preimmunization against host-specific DBA/2 non-H-2 antigens. To study the possible relationship between the observed protection and restoration of immune responsiveness, we compared spleen cellularity, selected T and B cell functions, and NK activity in GVH and protected mice during the 1st month after grafting. Normal and isografted mice served as controls. GVH was found to be characterized by an early stimulation phase associated with splenomegaly and increased percentages (but not numbers) of Lyt-2+ and L3T4+ cells, followed by profound aplasia and abrogation of IL-2 production. Response to a B cell mitogen (LPS) is depressed, and cells from GVH mice exert a strong suppressive effect on the LPS and PHA responsiveness of normal cells. Suppression appears to be mediated by a radioresistant, nylon nonadherent, asialo GM1 negative cell expressing a low level of Thy-1 antigen. In contrast, protection correlates with progressive restoration of spleen cellularity and LPS responsiveness, with decreased but clearly detectable IL-2 production, and transient nonspecific suppressor activity. The immune status of protected mice resembles that of isografted controls. No correlation was found between mortality (or protection) and either PHA responsiveness, which remained depressed in all grafted mice throughout the observation period, or NK activity, which was strongly depressed in both GVH and protected mice. In conclusion, protection correlates with the disappearance of nonspecific suppressor cells and the restoration of cellularity and certain nonspecific immune functions. Donor immunization against host-specific non-H-2 antigens, which protects against mortality, also protects against GVH-associated immune deficiency.
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PMID:Lethal graft-versus-host reaction against non-H-2 antigens. I. Prevention of GVH-associated immunodeficiency by preimmunizing the donor against host-specific non-H-2 antigens. 252 8

Rat monoclonal antibodies (mAbs) of the same specificity (anti-Thy-1) but different immunoglobulin (Ig) subclass were investigated for their effect on suppression of graft-versus-host disease (GVHD) by depleting the marrow donors of T cells in vivo. Transplantation to homozygous, fully mismatched mice of spleen and bone marrow cells from unthymectomized mice injected with the mAbs revealed that two rat anti-Thy-1 mAbs with high affinity for C1q (IgG2b) suppressed and prevented acute and chronic mortality of GVHD. In contrast, rat mAbs with low affinity for C1q (IgM, IgG2c) barely delayed acute mortality. This correlated with findings on the degree of splenic T-cell depletion in donor mice with the IgG2b mAb, able to deplete 97%, and the IgG2c and IgM mAbs, only 83% and 75% of T cells, respectively. An effect akin to the one achieved with IgG2b was seen, however, when donor mice were thymectomized and then treated with three injections of IgG2c isotype. The rat IgM mAb was not immunosuppressive even under such conditions. Immunocytochemical and immunohistochemical examination of the donor lymph nodes after single injection of either mAb showed that only 84% of T cells were eliminated, and in contrast to the spleen, none of the tested antibodies could deplete T cells further. The thymus did not appear depleted at all, although the cortical thymocytes were coated with either of the injected mAbs.
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PMID:Antilymphocytic antibodies and marrow transplantation. IX. T-cell depletion in marrow donors with C1q high and low affinity antibodies for suppression of GVHD in fully mismatched mice. 257 Jul 11

We have studied the phenotype of mononuclear cells infiltrating target organs of mice with acute graft-versus-host disease after bone marrow transplantation from H-2-identical donors. Infiltrating mononuclear cells with characteristics of large granular lymphocytes (LGL) were frequently found in close association with dead or dying epithelial cells in the skin, liver, and colon. The phenotype of these putative effector cells was Thy-1+, ASGM1+, Mac-1+, Lyt-1-, Lyt-2-, Ia-, which is characteristic of LGL. Differences in the Thy-1 allele between donor and host were used to demonstrate that these cells were of donor origin. Analysis of cytolytic function in GVHD splenocytes indicated high natural killer activity and low cytolytic T lymphocyte (CTL) activity. These findings suggest that an important effector cell in systemic acute graft-versus-host disease is a large granular lymphocyte of donor origin.
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PMID:Evidence that large granular lymphocytes of donor origin mediate acute graft-versus-host disease. 264 31

Prompted by our recent finding that lymphokine-activated killer (LAK) cells mediate both veto and natural suppression, we tested the ability of adoptively transferred LAK cells to block two in vivo alloreactions which complicate bone marrow transplantation: resistance to transplanted allogeneic bone marrow cells, and lethal graft-vs-host disease. Adoptive transfer of either donor type B6D2 or recipient-type B6 lymphokine-activated bone marrow cells, cells found to have strong LAK activity, abrogated or inhibited the resistance of irradiated B6 mice to both B6D2 marrow and third party-unrelated C3H marrow as measured by CFU in spleen on day 7. The ability of lymphokine-activated bone marrow cells to abrogate allogeneic resistance was eliminated by C lysis depletion of cells expressing asialo-GM1, NK1.1, and, to a variable degree, Thy-1, but not by depletion of cells expressing Lyt-2, indicating that the responsible cells had a LAK cell phenotype. Similar findings were obtained by using splenic LAK cells generated by 3 to 7 days of culture with rIL-2. Demonstration that allogeneic resistance could be blocked by a cloned LAK cell line provided direct evidence that LAK cells inhibit allogeneic resistance. In addition to inhibiting allogeneic resistance, adoptively transferred recipient-type LAK cells prevented lethal graft-vs-host disease, and permitted long term engraftment of allogeneic marrow. Irradiation prevented LAK cell inhibition of both allogeneic resistance and lethal graft-vs-host disease. These findings suggest that adoptive immunotherapy with LAK cells may prove useful in preventing graft rejection and graft-versus-host disease in human bone marrow transplant recipients.
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PMID:Use of lymphokine-activated killer cells to prevent bone marrow graft rejection and lethal graft-vs-host disease. 266 9

An in vitro assay was used to determine whether mouse complement (C') was able to lyse T cells coated with a monoclonal IgM anti-Thy-1 antibody. Using lymph node cells (LNC) as targets, it was found that antibody-coated mature T cells were efficiently lysed by serum from C57BL/6, but inefficiently lysed by serum from BALB/c mice. Serum from both strains lysed antibody-coated thymocytes, demonstrating that BALB/c serum is not deficient in one of the C' components. The lytic activity of BALB/c serum could be improved by increasing the concentration of monoclonal anti-Thy-1 used to coat the target LNC. In contrast, serum from C5-deficient A/HeJ mice was unable to lyse either of the antibody-coated target cells in vitro. These in vitro results were confirmed in vivo using a model of lethal graft-versus-host disease (GVHD) induced to minor histocompatibility antigens. In this model, GVHD occurs when lethally irradiated mice are transplanted with bone marrow plus spleen cells from H-2-identical donor mice. GVHD is prevented when T cells are removed from the cells by in vitro treatment with anti-Thy-1 antibody plus rabbit C'. As predicted by the in vitro data, C57BL/6 mice were protected from GVHD when transplanted with LP cells treated with a 1:100 dilution of anti-Thy-1 antibody, but without complement, but BALB/c recipients of antibody-coated B10.D2/nSN cells were not. When the concentration of anti-Thy-1 used to coat the donor cells was increased to 1:50, 8 of 9 recipients were protected from GVHD. In contrast, none of the C5-deficient DBA/2 recipients of anti-Thy-1 (1:50 dilution) treated B10.D2 cells were protected from GVHD. Complement-mediated lysis appears to be the primary mechanism by which T cells coated with a monoclonal IgM anti-Thy-1 antibody are functionally inactivated in vivo.
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PMID:Prevention of graft-versus-host disease using antibody to Thy 1. A role for complement in vivo. 286 76

Eleven monoclonal antibodies of rat or mouse origin against the mouse pan T antigen Thy-1 were compared for their ability to reduce mortality from graft-versus-host disease (GVHD) when incubated with donor marrow. Spleen and bone marrow cells were transferred to F1 hybrids or to fully allogeneic (H-2 I-A incompatible) mice. Particular attention was paid to whether complement (rabbit) enhanced the anti-GVHD effect of the antibodies in homozygous histoincompatible chimeras: without complement, 5 IgM anti-Thy-1 and 2 IgG2a anti-Thy-1 did not reduce GVHD. With complement, acute GVHD was completely suppressed. Two of two rat IgG2b anti-Thy-1, however, suppressed acute GVHD without the need for added complement. One of the two also prevented chronic mortality following two haplotype-unmatched transplantation. This antibody, in contrast to other complement-fixing anti-Thy-1 antibodies, had previously been shown to delay rejection of skin allografts. Its specificity did not differ from other complement-dependent Thy-1 antibodies when tested in a cross-blocking radioimmunoassay, and it also had the lower affinity for Thy-1. It seems therefore that only a minority of the antibodies were able to fully exploit the marrow recipients' opsonizing capacity for suppression of GVHD. The important clinical implications of the remarkable difference in immunosuppression of various monoclonal antibodies with comparable specificity and capacity to fix complement in vitro are discussed.
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PMID:Antilymphocytic antibodies and marrow transplantation. VII. Two of nine monoclonal anti-Thy-1 antibodies used for pretreatment of donor marrow suppressed graft-versus-host reactions without added complement. 286 78

Daunomycin coupled via an acid-sensitive spacer to monoclonal Thy-1.2-specific antibody was used to purge T lymphocytes from a 1:1 mixture of murine C57BL/6J bone marrow and spleen cells prior to engraftment in fully allogeneic, irradiated BALB/c recipients. Treatment of bone marrow with the immunotoxin at a concentration used for purging had no effect on the viability of committed hematopoietic progenitor or multipotent stem cells. All of the recipients of purged bone marrow were at least 80% chimeric for donor peripheral blood cells and none developed graft-versus-host disease. Out of 50 chimeras, 49 were still alive more than 200 days posttransplantation. The chimeras were shown to be tolerant to donor tissue as tested by mixed lymphocyte reactivity, cell-mediated cytotoxicity, and skin grafting. The same tests revealed full immunocompetence of chimeras to third-party alloantigens. In vivo IgM and IgG antibody responses to sheep red blood cells were similar in magnitude in allogeneically and syngeneically reconstituted mice.
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PMID:Facilitation of allogeneic bone marrow transplantation by a T cell-specific immunotoxin containing daunomycin. 289 91

The current studies were designed to evaluate the effectiveness of marrow transplantation within and outside the major histocompatibility complex (MHC) on the long-term survival and occurrence of spontaneous leukemia in AKR mice. AKR mice, which were lethally irradiated and received MHC-matched marrow from CBA/J mice (CBA----AKR), never developed leukemia and were alive and remained healthy for up to 280 days post-transplant. These long-term surviving chimeras possessed substantial immune vigor when both cell-mediated and humoral responses were tested. Lethally irradiated AKR mice, which had received MHC-mismatched marrow (anti-Thy-1.2 treated or nontreated) from C57BL/6J mice (B6----AKR), never developed leukemia and survived up to 170 days post-transplant. However, both groups of these chimeras began dying 180 to 270 days post-transplant due to a disease process which could not be readily identified. Histological analysis of B6----AKR chimeras revealed severe lymphoid cell depletion in thymus and spleen; however, none of these chimeras exhibited classical features of acute graft versus host disease. Concanavalin A mitogenesis, primary antibody responses to sheep red blood cells and the production of interleukin 2 (IL-2) were suppressed in B6----AKR chimeras. IL-2 treatment of B6----AKR chimeras was shown to partially correct these deficiencies without stimulating mixed lymphocyte responsiveness to donor or host lymphocytes. These studies indicate that the use of MHC-mismatched marrow for the prevention of spontaneous AKR leukemia may rely on augmentative IL-2 therapy for complete immune reconstitution of leukemia-free chimeras.
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PMID:Leukemia prevention and long-term survival of AKR mice transplanted with MHC-matched or MHC-mismatched bone marrow. 294 11


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