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 incidence and severity of acute graft-versus-host disease (GVHD) after allogeneic transplantation using peripheral blood progenitor cells mobilized by granulocyte colony-stimulating factor (G-CSF) appear to be no worse than those after bone marrow transplantation, despite the presence of large numbers of T cells in the donor infusion. Experimental studies have shown that type-1 T cells (secreting interleukin-2 [IL-2] and interferon-gamma) mediate acute GVHD, whereas type-2 T cells (secreting IL-4 and IL-10) can prevent acute GVHD. We tested the hypothesis that G-CSF modulates T-cell function toward a type-2 response and thus reduces the severity of acute GVHD. B6 mice were injected with G-CSF or diluent for 4 days, and their splenic T cells were stimulated in vitro with alloantigen or mitogen in the absence of G-CSF. T cells from G-CSF-treated mice showed a significant increase in IL-4 production, with a simultaneous decrease in IL-2 and interferon-gamma production in response to both stimuli. We also examined the effect of G-CSF pretreatment of donors in a GVHD model (B6-->B6D2F1). Survival was significantly improved in recipients of G-CSF-treated donors. Concanavalin-A-induced cytokine production at day 13 after transplantation also showed an increase in IL-4 along with a decrease in IL-2 and IFN-gamma production by splenocytes from recipients of G-CSF-treated bone marrow and T cells. These data show that pretreatment of donors with G-CSF polarizes donor T cells toward the production of type-2 cytokines, which is associated with reduced type-1 cytokine production and reduced severity of acute GVHD.
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PMID:Pretreatment of donor mice with granulocyte colony-stimulating factor polarizes donor T lymphocytes toward type-2 cytokine production and reduces severity of experimental graft-versus-host disease. 854 30

In this study, we have investigated cytokine (IL-1 beta, IL-2, IL-5, IL-6, IFN-gamma, TNF-alpha) and T cell surface molecule (IL-2 receptor, CD28, CTLA-4) gene expression in two way mixed lymphocyte cultures (MLC) enhanced by concanavalin A (ConA) to assess whether this is a useful predictive method for severe graft-versus-host disease (GVHD) and graft failure in allogeneic bone marrow transplantation (allo BMT) patients. Our present study revealed increased mRNA expression of IL-2, IL-5 and IFN-gamma using this assay in patients with delayed engraftment followed by graft failure and patients who developed grade III acute GVHD. Elevated IL-2 and IFN-gamma levels in MLC medium were also observed in these patients. Concerning T cell surface molecule gene expression in our modified MLC, IL-2 receptor gene expression was not altered so much in allo BMT patients, however, CD28 and CTLA-4 gene expression were elevated in patients with graft failure and severe acute GVHD. The elevated expression of cytokines (IL-2, IL-5 and IFN-gamma) and T cell surface molecules (CD28 and CTLA-4) mRNA in our modified MLC, in patients who developed severe lethal transplantation-related complications may suggest an important role for these molecules in inducing a strong alloresponse. Therefore, the detection of increased gene expression of those molecules, in our modified MLC system, appeared to be useful for predicting transplantation-related complications in allo BMT patients. In addition, this modified MLC assay may also be useful for the selection of the most compatible related and unrelated donors.
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PMID:Transplantation-related complications predicted by cytokine gene expression in the mixed lymphocyte culture in allogeneic bone marrow transplants. 857 69

Graft-versus-host disease (GVHD) remains the major complication of allogeneic bone marrow transplantation. T cells in donor bone marrow recognize and react to host alloantigens and thereby initiate GVHD, but the precise mechanisms by which host tissues are damaged remain unclear. Recently, several convergent lines of evidence suggested that inflammatory cytokines act as mediators of acute GVHD. Most of the clinical manifestations of GVHD may, in fact, be due to the dysregulated production of cytokines by T cells and other inflammatory cells. The complex interactions among cytokines and their cellular targets suggest that individual cytokines may play an important and distinctive role in the pathophysiology of GVHD. Perturbation of the cytokine network may function as a final common pathway of target organ damage, and the rapid onset of severe, acute GVHD can be considered a "cytokine storm."
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PMID:Cytokine inhibitors and graft-versus-host disease. 859 63

Membrane receptors for blood proteases govern the clotting and fibrinolytic cascades, regulate signal transduction and control the growth of mesenchymal cells. Despite their importance in the development of vascular injury, it is unclear whether these mechanisms participate in the generation of an immune response. Here we report that targeting a factor Xa receptor, designated effector cell protease receptor-1 (EPR-1), with antisense oligonucleotide or with a monoclonal antibody (mAB 2E1) inhibited CD3/T-cell receptor-dependent lymphocyte proliferation. Immunosuppression was mediated by abolishing cytokine production and down-modulating membrane expression of the interleukin (IL)-2 receptor. In vivo administration of mAb 2E1 to severe-combined-immunodeficient mice injected with human peripheral blood leukocytes suppressed production of human immunoglobulin, abolished graft-versus-host disease, and protected these xenochimaeric mice from Epstein-Barr-virus-induced human lymphoproliferative disease. These observations indicate a new role for protease receptors in the regulation of the immune response, and identify a potential target for therapeutic immunosuppression in humans.
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PMID:In vivo immunosuppression by targeting a novel protease receptor. 859 23

Rapamycin (RAPA) has been shown to be a highly effective means of reducing the lethality of graft-versus-host disease (GVHD) in B10.BR recipients of allogeneic C57BL/6 donor cells. RAPA-treated mice had no clinical (e.g., weight loss, diarrhea, lethargy) or histologic evidence of classical acute or chronic GVHD but did develop a clinical-pathological syndrome consisting of ulcerative dermatitis, bile duct proliferation, and a nondestructive peribronchiolar pulmonary infiltration. Because RAPA was found to interfere with the deletion of self-reactive T cells, we wondered whether the RAPA-induced syndrome was related to failed negative selection or altered alloreactivity. We now show that the RAPA-induced syndrome is due to effects on mature, donor-derived alloreactive T cells. By titering the number of T cells infused we were able to vary the syndrome incidence. In contrast to the syndrome seen after cyclosporin A (CsA) administration, the RAPA syndrome did not require an intact thymus and the disease could not be adoptively transferred. The addition of CsA (which blocks T-cell cytokine production) to RAPA (which blocks T-cell cytokine response) prevented the generation of this syndrome, suggesting that the tissue manifestations seen in RAPA only treated recipients were caused by cytokine production and release. RAPA also caused this alloimmune syndrome in recipients of minor histocompatibility antigen disparate donor cells, showing that the RAPA effects were not restricted to a single donor-recipient strain combination or to instances in which the donor and recipient were fully major histocompatibility complex disparate. We conclude that RAPA is a highly effective means of preventing murine acute GVHD, and that when combined with CsA, warrants consideration for human investigations.
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PMID:In vivo inhibition of cytokine responsiveness and graft-versus-host disease mortality by rapamycin leads to a clinical-pathological syndrome discrete from that observed with cyclosporin A. 861 33

Intravenous immune globulin (IVIG) exhibits a number of immunomodulatory properties that are mediated by the Fe portion of IgG and by the spectrum of variable (V) regions contained in the immune globulin preparations. Five predominant and non-exclusive mechanisms of action have been proposed to account for the immunomodulatory effects of IVIG in immune-mediated diseases: (i) functional blockade of Fc receptors on splenic macrophages; (ii) inhibition of complement-mediated damage, an effect that is dependent on the ability of IgG to bind C3b and C4b and thus reduce the number of activated complement fragments that may deposit on target surfaces of complement activation; (iii) modulation of the production of cytokines and cytokine antagonists; (iv) neutralization of circulating autoantibodies by complementary (e.g. anti-idiotypic) antibodies in IVIG, a mechanism that accounts for the rapid decrease in titre of circulating autoantibodies that is often observed within hours following the infusion of IVIG; (v) selection of immune repertoires, a complex set of effects that may be observed in individuals receiving IVIG far beyond the half-life of the infused immunoglobulin and that is directly relevant to the ability of IVIG to, for example, suppress autoantibody-producing clones in patients with antibody-mediated autoimmune disease and modulate graft versus host disease (GVHD). IVIG has been shown to downregulate or activate B-cell clones expressing surface IgG that is complementary (anti-idiotypic) to V regions of antibodies present in IVIG. IVIG has been shown also to interact with surface molecules of T cells that are essential to immune regulation, such as the alpha beta TCR, CD5, CD4, non-polymorphic determinants of MHC class I molecules and adhesion molecules of T and B cells. The complex interactions of IVIG with functional molecules of cells of the immune system are relevant to its therapeutic effects in T cell- as well as B cell-mediated diseases and indeed, to our understanding of the physiological role of normal IgG and antibody networks in controlling autoreactivity in healthy individuals.
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PMID:Mechanisms of action of intravenous immune globulin in immune-mediated diseases. 862 40

Graft-versus-host disease (GVHD) is initiated by adoptively transferred donor T cells that recognize host alloantigens. Whereas the absence of donor T-cell proliferation to host alloantigens in a mixed-leukocyte reaction does not predict freedom from GVHD, the frequency of alloreactive precursor helper T lymphocytes (pHTL) is predictive. Complete blockade of 87 family-mediated costimulation, but not of major histocompatibility complex recognition or adhesion, induces host alloantigenic-specific energy by reducing cytokine production below threshold levels necessary for common gamma chain signaling. The associated reduction of alloreactive pHTL frequency below that predictive for GVHD, without depletion of either nonallospecific T cells or hematopoietic progenitors, has led us to embark upon human clinical trials of haplomismatched allogeneic bone marrow transplantation.
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PMID:Complete blockade of B7 family-mediated costimulation is necessary to induce human alloantigen-specific anergy: a method to ameliorate graft-versus-host disease and extend the donor pool. 863 63

The development of graft-versus-host disease (GVHD) is associated with long-lasting and profound deficits in immune function that lead to increased morbidity and mortality after bone marrow transplantation (BMT). We investigated a mechanism of T-cell immunodeficiency in response to mitogen or alloantigen in an experimental model of acute GVHD by analyzing the roles of two immunosuppressive moieties: interferon gamma (IFN-gamma) and nitric oxide (NO). Splenocytes from mice with GVHD did not proliferate either to the T-cell mitogen, concanavalin A (Con A), or to host alloantigens, but only mitogen-activated cultures produced increased levels of NO. The abrogation of NO synthesis with LG-mono-methyl-arginine (NMMA) restored mitogen-induced proliferation but not the response to host antigens. The mechanism of impared proliferation to mitogen was dependent on IFN-gamma because blockade of this cytokine in culture inhibited NO production and restored proliferation to Con A to levels similar to those in transplanted control mice without GVHD. NMMA did not substantially reduce IFN-gamma levels, demonstrating that NO acted distally to IFN-gamma in the pathway of immunosuppression in response to mitogen. Furthermore, the prevention of IFN-gamma production in vivo after allogeneic BMT, by transplantation of polarized type 2 donor T cells (secreting interleukin-4 but not IFN-gamma), also prevented NO production and restored splenocyte responses to mitogen. Our data demonstrate the existence of NO-dependent and NO-independent pathways involved in suppression of T-cell proliferation during acute GVHD. Excess NO synthesis appears to be one mechanism by which IFN-gamma induces immunodeficiency after allogeneic BMT.
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PMID:Interferon-gamma suppresses T-cell proliferation to mitogen via the nitric oxide pathway during experimental acute graft-versus-host disease. 870 22

Interleukin-12 (IL-12) is a critical cytokine regulating natural killer (NK) and T-cell function. We hypothesized that the impaired ability of cord blood (CB) to produce normal adult levels of IL-12 in response to stimulation may contribute to the immaturity of CB immunity. Furthermore, exogenous IL-12 may compensate for the immaturity in CB cellular immunity and have the potential for immunotherapy post cord blood transplantation. We compared the expression and production of IL-12 from activated cord versus adult mononuclear cells (MNC), regulatory mechanisms associated with IL-12 expression in CB MNC, and the effects of IL-12 on induction of CB interferon (IFN)-gamma production, NK, and lymphokine-activated killer (LAK) cytotoxicity. Northern analysis and enzyme-linked immunosorbent assay were performed in lipopolysaccharide (LPS)-stimulated CB and adult peripheral blood (APB) MNC. IL-12 mRNA expression was induced within 6 hours with LPS (10 micrograms/ml) and reached peak levels at 12 hours in both CB and APB MNC. However, IL-12 mRNA expression and protein accumulation in CB MNC were 35.8% +/- 4.84% (12 hours, n = 11, P < .05), and 17.6% +/- 1.7% (24, 72, 96 hours, n = 9, P < .05) respectively, when compared with APB MNC. Nuclear run-on assays showed no differences between CB and APB MNC in both the basal levels of transcription and the degree of transcriptional activation. However, the half-life of IL-12 p40 mRNA was approximately threefold lower in activated CB MNC than in activated APB MNC (CB: 114 +/- 3.0 minutes v APB: 353 +/- 7.8 minutes, n = 3, P < .05). Exogenous IL-12 (10 U/mL) induced a significant increase of IFN-gamma from both CB and APB MNC (24 hours, 72 hours, P < .05, n = 3). The stimulated CB IFN-gamma level reached comparable levels produced by unstimulated APB. IL-12 treatment also significantly enhanced CB NK cytotoxicity against K562 and NB-100 cell lines to the comparable levels of APB (P < .05, n = 4). CB MNC was more responsive to IL-12 stimulation with respect to IFN-gamma production, NK, and LAK cytotoxicity when compared with APB. The present study suggests that IL-12 mRNA and protein expression is decreased in activated CB. This discrepancy in IL-12 production is secondary, at least in part, to the altered posttranscriptional regulation. The impaired, ability of CB MNC to produce IL-12 in response to stimulation may contribute to the decrease in IFN-gamma production and NK cytotoxicity. However, IL-12 enhanced IFN-gamma and NK activity in CB MNC up to the comparable levels of APB MNC. These findings suggest that reduced expression and production of IL-12 from activated CB may contribute to the immaturity in CB cellular immunity and contribute, in part, to decreased graft-versus-host disease following CB stem cell transplantation.
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PMID:Decreased interleukin-12 (IL-12) from activated cord versus adult peripheral blood mononuclear cells and upregulation of interferon-gamma, natural killer, and lymphokine-activated killer activity by IL-12 in cord blood mononuclear cells. 870 53

Intensification of therapeutic regimens, improved patient survival, and advances in cytokine and cellular therapies have led to increasingly complex requirements for transfusion and stem cell support in cancer treatment. This article focuses on current and evolving issues in red blood cell, platelet, and granulocyte transfusion support, as well as measures to avoid increasingly important complications of transfusion therapy, such as alloimmunization, graft-versus-host disease, cytomegalovirus infection, and immunomodulation. Issues concerning current applications of hematopoietic stem cell transplantation and future prospects also are discussed.
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PMID:Transfusion and stem cell support in cancer treatment. 870 62


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