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)

Two types of lupus mice, NZB/NZW F1 female hybrids and mice with graft-versus-host disease (GVHD), were studied. Histones H3 and H2A were detected by immunofluorescence in glomeruli of 22/22 proteinuric GVHD and 8/12 proteinuric NZB/W F1 female mice; in non-proteinuric animals, 3/5 GVHD and 2/27 NZB/W F1 female were positive. Using antibodies to histone peptides it was shown that mainly the N-terminal regions of histones H3 and H2A were exposed in glomerular deposits. Western blot analysis revealed antibodies to histone subfractions in sera of 33/34 lupus mice that developed proteinuria. This study provides evidence that histones are involved in the pathogenesis of lupus nephritis.
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PMID:Glomerular immune deposits in murine lupus models may contain histones. 145 82

In spite of intensive endeavours, attempts to identify nephritogenic antigens in cases of immune complex glomerulonephritis have not yielded convincing results. Cationic antigens can have high affinity for the glomerular basement membrane and are prime candidates as nephritogens. They can be expected to play a role in post-infectious and in autoimmune glomerular disease. Histones show great promise in the latter case: we are able to demonstrate (1) a high affinity for the glomerular basement membrane and (2) their ability to promote glomerular deposition of anionic antigens as an additional target. Histones were detectable in glomerular deposits in two murine models of glomerulonephritis: the spontaneous lupus-like disease of NZB/W F1 mice and in graft-versus-host disease. We propose that histones may be responsible for the induction of glomerulonephritis in lupus-like syndromes, as well as other types of autoimmune renal disease. As an analogue, histone-like proteins from micro-organisms may also be responsible for glomerular disease in post-infectious nephritis.
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PMID:The role of cationic proteins in the pathogenesis of immune complex glomerulonephritis. 215 42

Native preparations of evolutionarily conserved intracellular macromolecules are generally nonimmunogenic when injected in soluble form. However, vigorous immune responses were observed when common autoantigens such as histones, DNA or Sm antigen, or homologous liver homogenate were noncovalently coupled to latex beads prior to injection into mice. Antibody response to histone beads displayed immunologic memory and required a functional thymus, suggesting that T-helper cells were involved. However, bead-elicited autoantibodies could be distinguished from true autoantibodies in that they reacted with denatured, minor, or foreign components of the preparations or to regions unexposed in the native form of the immunogen. This response contrasted with spontaneously arising autoantibodies accompanying graft-versus-host (GVH) disease in the same strain of mice which preferred native nucleoprotein conformations within nuclei, chromatin, or DNA-histone complexes. Histone beads elicited antihistone antibodies displaying a sustained IgM isotype in contrast to spontaneously arising autoantibodies in GVH disease which were predominantly IgG. These studies demonstrate that immunization with autoantigens does not usually elicit true autoantibodies and suggest that lymphocyte populations responsible for pseudoautoimmune responses are different from autoantibody-producing cells. We speculate that if autoimmunity is driven by particulate forms of in vivo self-materials, additional factors are required for breaking the natural tolerance to native conformations within the immunogen.
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PMID:Pseudoautoimmunity in normal mice: anti-histone antibodies elicited by immunization versus induction during graft-versus-host reaction. 229 57

A lupus-like disease characterized by a severe immune complex glomerulonephritis and IgG autoantibody production was induced in (C57BL/6 X DBA/2)F1 mice by injection of parental DBA/2 lymphoid cells. The ensuing graft-vs-host (GVH) reaction resulted in a 10- and a 100-fold increase in serum IgG antibody levels to denatured DNA and total histones, respectively, compared with that in F1----F1 control mice. The level of anti-DNA antibodies peaked 2 wk after injection of DBA/2 cells and preceded peak anti-histone levels by approximately 2 wk. Anti-histone antibodies were generated predominantly to histones H1, H2A, and H2B, a profile different from that observed in NZB/NZW and MRL-lpr/lpr mice. The marked increase in IgG antinuclear antibodies did not correlate with increases in total IgG serum levels and was not associated with comparable increases in antibodies to transferrin, hemoglobin, fibrinogen, or thyroglobulin. Selective autoantibody production was also observed in vitro, wherein GVH spleen cells produced high levels of IgG antibodies to total histones and denatured DNA but not to these non-nuclear protein antigens. In contrast, spleen cells stimulated in vitro with lipopolysaccharide produced equivalent amounts of antibodies to all antigens tested. Our results are in agreement with those of other investigators and collectively suggest that IgG autoantibodies in GVH disease, and possibly in spontaneous lupus-like disease, are not secondary to a generalized B cell activation, but may be selectively generated in response to self antigens with unique configurational properties.
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PMID:Autoimmunization in murine graft-vs-host disease. I. Selective production of antibodies to histones and DNA. 387 58

Chronic graft-versus-host disease (GVHD) was induced in female (C57 B10S/DBA/2)F1 hybrid mice with two successive injections of lymphoid cells from parental DBA/2 strain. Serial bleedings of 27 GVHD mice were screened with a panel of antigens including the five histones H1, H2A, H2B, H3 and H4, 15 histone peptides, core particles, dsDNA, heat-shock proteins hsp70 and ubiquitin, a branched peptide of ubiquitinated H2A (U-H2A), poly(ADP-ribose) and SSB/La protein. The predominant IgG response to histone peptides was directed against regions 204-218 of H1, 1-25 of H2B and 1-29 of H4. GVHD mice also produced IgG antibodies to dsDNA and chromatin core particles as reported previously. IgG antibodies reacting with dsDNA appeared before antibodies to core particles and histones. Raised levels of antibodies to U-H2A, but not to monomeric ubiquitin, were also found. While the level of antibodies to dsDNA, histones and core particles decreased significantly before the appearance of proteinuria, suggesting their involvement in glomerular injury, the longitudinal pattern of anti-U-H2A peptide response was apparently not linked to the manifestation of lupus nephritis in GVHD mice.
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PMID:Antibodies to DNA, chromatin core particles and histones in mice with graft-versus-host disease and their involvement in glomerular injury. 795 35

Acute graft-versus-host disease (GVHD) and leukemic relapse are the two major obstacles to successful outcomes after allogeneic bone marrow transplantation (BMT), an effective therapy for hematological malignancies. Several studies have demonstrated that the dysregulation of proinflammatory cytokines and the loss of gastrointestinal tract integrity contribute to GVHD, whereas the donor cytotoxic responses are critical for graft-versus-leukemia (GVL) preservation. Suberoylanilide hydroxamic acid (SAHA) is currently in clinical trials as an antitumor agent; it inhibits the activity of histone deacetylases and at low doses exhibits antiinflammatory effects by reducing the production of proinflammatory cytokines. Using two well characterized mouse models of BMT, we have studied the effects of SAHA on GVHD severity and GVL activity. Administration of SAHA from day +3 to day +7 after BMT reduced serum levels of the proinflammatory cytokines and decreased intestinal histopathology, clinical severity, and mortality from acute GVHD compared with vehicle-treated animals. However, SAHA had no effect on donor T cell proliferative and cytotoxic responses to host antigens in vivo or in vitro. When mice received lethal doses of tumor cells at the time of BMT, administration of SAHA did not impair GVL activity and resulted in significantly improved leukemia-free survival by using two different tumor and donor/recipient combinations. These findings reveal a critical role for histone deacetylase inhibition in the proinflammatory events contributing to GVHD and suggest that this class of pharmacologic agents may provide a strategy to reduce GVHD while preserving cytotoxic T cell responses to host antigens and maintaining beneficial GVL effects.
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PMID:Histone deacetylase inhibitor suberoylanilide hydroxamic acid reduces acute graft-versus-host disease and preserves graft-versus-leukemia effect. 1500 2

Clinical responses of solid tumors after allogeneic human leukocyte antigen-matched stem cell transplantation (SCT) often coincide with severe graft-versus-host disease (GVHD). Targeting minor histocompatibility antigens (mHags) with hematopoiesis- and cancer-restricted expression, for example, HA-1, may allow boosting the antitumor effect of allogeneic SCT without risking severe GVHD. The mHag HA-1 is aberrantly expressed in cancers of most entities. However, an estimated 30% to 40% of solid tumors do not express HA-1 (ie, are HA-1(neg)) and cannot be targeted by HA-1-specific immunotherapy. Here, we investigated the transcriptional regulation of HA-1 gene expression in cancer. We found that DNA hypermethylation in the HA-1 promoter region is closely associated with the absence of HA-1 gene expression in solid tumor cell lines. Moreover, we detected HA-1 promoter hypermethylation in primary cancers. The hypomethylating agent 5-aza-2'-deoxycytidine induced HA-1 expression only in HA-1(neg) tumor cells and sensitized them for recognition by HA-1-specific cytotoxic T lymphocytes. Contrarily, the histone deacetylation inhibitor trichostatin A induced HA-1 expression both in some HA-1(neg) tumor cell lines and in normal nonhematopoietic cells. Our data suggest that promoter hypermethylation contributes to the HA-1 gene regulation in tumors. Hypomethylating drugs might extend the safe applicability of HA-1 as an immunotherapeutic target on solid tumors after allogeneic SCT.
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PMID:Hypomethylating drugs convert HA-1-negative solid tumors into targets for stem cell-based immunotherapy. 1909 14

Histone methylation is thought to be important for regulating Ag-driven T-cell responses. However, little is known about the effect of modulating histone methylation on inflammatory T-cell responses. We demonstrate that in vivo administration of the histone methylation inhibitor 3-deazaneplanocin A (DZNep) arrests ongoing GVHD in mice after allogeneic BM transplantation. DZNep caused selective apoptosis in alloantigen-activated T cells mediating host tissue injury. This effect was associated with the ability of DZNep to selectively reduce trimethylation of histone H3 lysine 27, deplete the histone methyltransferase Ezh2 specific to trimethylation of histone H3 lysine 27, and activate proapoptotic gene Bim repressed by Ezh2 in antigenic-activated T cells. In contrast, DZNep did not affect the survival of alloantigen-unresponsive T cells in vivo and naive T cells stimulated by IL-2 or IL-7 in vitro. Importantly, inhibition of histone methylation by DZNep treatment in vivo preserved the antileukemia activity of donor T cells and did not impair the recovery of hematopoiesis and lymphocytes, leading to significantly improved survival of recipients after allogeneic BM transplantation. Our findings indicate that modulation of histone methylation may have significant implications in the development of novel approaches to treat ongoing GVHD and other T cell-mediated inflammatory disorders in a broad context.
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PMID:Inhibition of histone methylation arrests ongoing graft-versus-host disease in mice by selectively inducing apoptosis of alloreactive effector T cells. 2230 80

Selective depletion of the alloreactive T cells causing graft-versus-host disease (GVHD) without loss of the graft-versus-leukemia (GVL) effect is the holy grail of hematopoietic cell transplantation (HCT). In this issue of Blood, He et al demonstrate that inhibition of histone methylation leads to selective apoptosis of the alloreactive effector cells. Moreover, they demonstrate that this inhibition of histone methylation remarkably stops ongoing GVHD.
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PMID:Control of GVHD: it's in our DNA! 2211 46

Histone deacetylase inhibitors (HDACis) are a new class of compounds that induce acetylation of histone lysine tails in chromatin and modify gene expression. The Food & Drug Administration approved HDACi, Vorinostat, or suberoylanilide hydroxamic acid (SAHA), has been shown to inhibit tumor cell growth and the production of proinflammatory cytokines. In preclinical allogeneic transplant models, SAHA induces graft-versus-host disease (GVHD) amelioration in treated mice without impairing graft-versus-leukemia. LBH589 (Panobinostat), a structurally novel cinnamic hydroxamic acid class, is an HDACi more potent than SAHA. In the current work, we tested the hypothesis that LBH589 would be highly effective in the prevention of GVHD. Using mouse model of allogeneic bone marrow transplant (BMT), we unexpectedly found that treatment with LBH589 accelerated GVHD, in contrast to the treatment with SAHA that alleviated GVHD. Accelerated GVHD in the recipients treated with LBH589 was associated with elevated Th1 cytokines in recipient serum, enhanced CXCR3 expression on donor T cells, and T cell infiltration in the liver. The current study highlights the distinct effects of pan HDACi on allogeneic BMT and alerts that LBH589 (Panobinostat) could have an adverse effect on GVHD, and possibly on other inflammatory diseases.
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PMID:LBH589 enhances T cell activation in vivo and accelerates graft-versus-host disease in mice. 2269 84


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