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)

A major benefit of allogeneic hematopoietic cell transplantation (HCT) in the treatment of malignancies is the graft-versus-tumor (GVT) effect conferred by lymphocytes contained within the graft. However, lymphocytes can also induce the potentially lethal complication of graft-versus-host disease (GVHD). We have previously reported a method of generating large numbers of ex vivo activated and expanded T cells with antitumor activity after culture with interferon-y, cross-linking antibodies to CD3, and interleukin-2. Murine splenocytes expanded under these conditions are a heterogeneous population of which approximately 20% to 60% of cells express natural killer (NK)-cell markers (NK1.1 and DX5) and display major histocompatibility complex (MHC)-unrestricted antitumor activity. Here we demonstrate the in vivo antitumor activity of this population of expanded CD8+ NK-T cells when transplanted across MHC barriers into tumor-bearing hosts. In cotransfer studies with purified allogeneic hematopoietic stem cells, expanded CD8+ NK-T cells confer GVT activity with minimal to no GVHD. In vitro studies show that, although expanded NK-T cells lyse normal allogeneic bone marrow cells, they preferentially mediate cytolysis against tumor targets. These cells persist in the peripheral circulation of host animals for at least 3 weeks posttransfer. GVT activity is dependent on perforin, but not on Fas-ligand. We conclude that expanded CD8+ NK-T cells may serve as a valuable adjuvant population for allogeneic HCT because they mediate GVT effects with minimal GVHD.
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PMID:Engineering hematopoietic grafts: purified allogeneic hematopoietic stem cells plus expanded CD8+ NK-T cells in the treatment of lymphoma. 1176 85

Adoptive cellular therapy holds promise for improving the outcome of hematopoietic cell transplantation (HCT). At present, donor lymphocyte infusion post-HCT is efficacious for only a limited number of diseases, yet can induce significant graft versus host disease (GVHD). To improve the outcome of this approach, it would be beneficial to identify populations of T cells that retain graft versus tumor (GVT) effects with reduced propensity for GVHD. Here we describe studies of both human and murine expanded CIK cells or CD8+ NK-T cells. These related populations of cells are ex vivo activated and expanded T cells that express both T and NK markers. They can be generated from patients with malignancies and mediate cytotoxicity against autologous hematopoietic malignancies. Recent work in murine models show that these cells mediate cytotoxicity by using a perforin-granzyme and not through Fas ligand. In allogeneic stem cell transplantation experiments, large numbers of expanded CD8+ NK-T cells could be transplanted across major histocompatibility barriers without causing severe GVHD and GVT effects were retained. We conclude that expanded CD8+ NK-T cells are a promising form of cellular therapy in the allogeneic setting.
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PMID:Studies of ex vivo activated and expanded CD8+ NK-T cells in humans and mice. 1207 54

L-leucyl-L-leucine methyl ester (LLME) prevents GVHD in several animal models by depleting dipeptidyl peptidase I (DPPI)-expressing cytotoxic cellular subsets. However, clinical application has been hampered by difficulties in stem cell engraftment following treatment of donor bone marrow inocula with LLME at the concentrations necessary to purge DPPI-expressing T-cells. Noting that T-cells can mediate graft-versus-leukemia (GVL) responses via both perforin (usually co-expressed in cytotoxic granules with DPPI) and Fas ligand pathways in a murine model, we hypothesized that LLME might be useful for treatment of delayed DLIs for potential GVL activity with a decreased risk of GVHD induction. In regard to the clinical setting, the ex vivo use of LLME for this purpose would circumvent any toxicity issues for donor stem cells, because by that time patients would have already achieved successful engraftment. For our preclinical studies, we used the haploidentical C57BL/6 (B6) (H2b) --> ((B6 x DBA/2)F1 (H(2b/d)) murine model with lethally irradiated hosts that had received transplants of T-cell-depleted bone marrow cells and were challenged with the MMD2-8 myeloid leukemia line (H2d) of DBA/2 origin. A DLI of LLME-treated donor splenocytes, from B6 mice presensitized to recipient alloantigens, was administered in varying doses 14 days post-marrow transplantation, and the potential for both GVHD and GVL activity was assessed. All mice that received any dose of LLME-treated DLI survived indefinitely, without evidence of cachexia nor B-cell hypoplasia, in contrast to the severe and lethal GVHD induced by mock-treated DLI. Histological analysis largely correlated with the symptomatic findings and revealed no GVHD-like lesions in the spleens of LLME-treated DLI recipients, although some mice displayed various degrees of hepatic mononuclear infiltration. Most notably, mice given LLME-treated DLI also experienced DLI dose-dependent increases in survival against the challenge with the MMD2-8 leukemia. LLME-treated splenocytes remained immunocompetent, as these cells could proliferate in response to mitogens and to restimulation with ovalbumin when used as a recall antigen. In conclusion, LLME-treated DLI possesses immune potential and, in particular, GVL activity without inducing clinically evident GVHD.
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PMID:Leucyl-leucine methyl ester-treated haploidentical donor lymphocyte infusions can mediate graft-versus-leukemia activity with minimal graft-versus-host disease risk. 1210 16

Sperm protein 17 (Sp17) is a highly immunogenic cancer-testis antigen expressed by tumour cells from up to 30% of patients with multiple myeloma (MM). We recently successfully generated Sp17-specific human leucocyte antigen (HLA)-A1 and B27-restricted cytotoxic T lymphocytes (CTLs) from the peripheral blood of a healthy donor. Because CTLs were able to kill HLA-matched fresh myeloma cells, it may be possible to generate and administer myeloma-specific donor T cells to MM patients following allogeneic stem cell transplantation to enhance graft-versus-myeloma (GVM) without inducing graft-versus-host disease (GVHD). To determine how widely applicable this approach is, we have determined the ability to generate Sp17-specific CTLs from four consecutive healthy donors with other HLA class I phenotypes. We found that Sp17-specific HLA class I-restricted CTLs could be easily generated from all four donors. Sp17-specific CTLs were primarily CD8 in phenotype and produced interferon-gamma and very little interleukin-4. These T cells killed target cells primarily via the perforin-mediated route. These results therefore suggest that myeloma-specific donor T-cell infusion that targets Sp17 to selectively enhance GVM could be applicable to patients with Sp17+ MM.
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PMID:Successful generation of sperm protein 17 (Sp17)-specific cytotoxic T lymphocytes from normal donors: implication for tumour-specific adoptive immunotherapy following allogeneic stem cell transplantation for Sp17-positive multiple myeloma. 1223 64

We have recently shown that early administration of interleukin 18 (IL-18) after bone marrow transplantation (BMT) attenuates acute graft-versus-host disease (GVHD) in a lethally irradiated parent into F1 (B6-->B6D2F1) BMT model. In this study, we investigated whether IL-18 can maintain graft-versus-leukemia (GVL) effect in this context. B6D2F1 mice received transplants of T-cell-depleted (TCD) bone marrow (BM) and splenic T cells from either syngeneic (H2(b/d)) or allogeneic B6 (H2(b)) donors. Recipient mice were treated with recombinant murine IL-18 or the control diluent. Initial studies demonstrated that IL-18 treatment did not affect the proliferative responses or the cytolytic effector functions of T cells after BMT. In subsequent experiments, animals also received host-type P815 mastocytoma cells at the time of BMT. All syngeneic BM transplant recipients died from leukemia by day 18. The allogeneic BM transplant recipients effectively rejected their leukemia regardless of treatment and IL-18 significantly reduced GVHD-related mortality. Examination of the cytotoxic mechanisms with perforin-deficient donor T cells demonstrated that perforin is critical for the GVL effect. Taken together these data demonstrate that IL-18 can attenuate acute GVHD without impairing the in vitro cytolytic function or the in vivo GVL activity after allogeneic BMT.
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PMID:Interleukin 18 preserves a perforin-dependent graft-versus-leukemia effect after allogeneic bone marrow transplantation. 1238 49

Acute graft-versus-host disease (GVHD) is thought to derive from direct T-cell injury of target tissues through perforin/granzyme, Fas/FasL interactions, and the effects of inflammatory cytokines. Animal models and some clinical trials support the notion that inhibition of inflammatory mediators such as interleukin-1 (IL-1), tumor necrosis factor alpha, and interferon gamma may ameliorate or prevent GVHD. We hypothesized that blockade of IL-1 during the period of initial T-cell activation would reduce the risk of severe GVHD. We tested this hypothesis in a double-blind, placebo-controlled randomized trial of recombinant human IL-1 receptor antagonist (IL-1Ra) in 186 patients undergoing allogeneic stem cell transplantation. Randomization was stratified by degree of histocompatibility and stem cell source. All patients were conditioned with cyclophosphamide and total body irradiation. GVHD prevention consisted of cyclosporine and methotrexate in all patients. Recombinant human IL-1Ra or saline placebo was given from day -4 to day +10. Randomization was stratified according to GVHD risk. The 2 groups were well-matched for pretreatment characteristics. Moderate to severe GVHD (grades B-D) developed in 57 (61%) of 94 patients receiving IL-1Ra and in 51 (59%) of 86 patients on placebo (P =.88). There was no difference in hematologic recovery, transplantation-related toxicity, event-free survival, or overall survival. We conclude that blockade of IL-1 using IL-1Ra during conditioning and 10 days immediately after transplantation is not sufficient to reduce GVHD or toxicity or to improve survival.
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PMID:Interleukin-1 blockade does not prevent acute graft-versus-host disease: results of a randomized, double-blind, placebo-controlled trial of interleukin-1 receptor antagonist in allogeneic bone marrow transplantation. 1239 61

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily that exhibits specific tumoricidal activity against a variety of tumors. It is expressed on different cells of the immune system and plays a role in natural killer cell-mediated tumor surveillance. In allogeneic hematopoietic-cell transplantation, the reactivity of the donor T cell against malignant cells is essential for the graft-versus-tumor (GVT) effect. Cytolytic activity of T cells is primarily mediated through the Fas-Fas ligand and perforin-granzyme pathways. However, T cells deficient for both Fas ligand and perforin can still exert GVT activity in vivo in mouse models. To uncover a potential role for TRAIL in donor T cell-mediated GVT activity, we compared donor T cells from TRAIL-deficient and wild-type mice in clinically relevant mouse bone-marrow transplantation models. We found that alloreactive T cells can express TRAIL, but the absence of TRAIL had no effect on their proliferative and cytokine response to alloantigens. TRAIL-deficient T cells showed significantly lower GVT activity than did TRAIL-expressing T cells, but no important differences in graft-versus-host disease, a major complication of allogeneic hematopoietic cell transplantation, were observed. These data suggest that strategies to enhance TRAIL-mediated GVT activity could decrease relapse rates of malignancies after hematopoietic cell transplantation without exacerbation of graft-versus-host disease.
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PMID:T cells require TRAIL for optimal graft-versus-tumor activity. 1242 60

After allogeneic stem cell transplantation (SCT), donor T-cells are primarily responsible for the antihost activity, resulting in graft-versus-host disease (GVHD). Three effector pathways have been described for T-cell cytotoxicity: perforin/granzyme B; Fas/Fas ligand (FasL) and secreted molecules such as TNF-alpha. The goal of this pilot study was to utilize competitive reverse transcription (RT)-PCR to evaluate the pattern of granzyme B, perforin, FasL and TNF-alpha gene expression in peripheral blood in patients after SCT. Protein levels of granzyme B, soluble FasL (sFasL) and TNF-alpha in plasma were also analyzed. Eight patients who underwent allogeneic SCT were included; five were diagnosed with acute GVHD. In the patients diagnosed with acute GVHD, we found increased levels of granzyme B, perforin and FasL mRNA, although this did not correlate with the clinical severity. However, patients with increasing levels of gene expression during acute GVHD treatment may have an increased risk of developing severe acute GVHD, as two out of three patients with increasing immune transcript levels during GVHD therapy developed life-threatening acute GVHD. In conclusion, the quantitative RT-PCR of granzyme B, perforin and FasL may serve as a guide to the clinician in diagnosing acute GVHD and monitoring treatment.
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PMID:Increased levels of immune transcript in patients with acute GVHD after allogeneic stem cell transplantation. 1262 79

Allogeneic bone marrow transplantation and donor lymphocyte infusion are powerful treatments for chemotherapy-resistant leukemia. Tumor eradication is attributed to a graft-versus-leukemia reaction by the donor-derived cytotoxic T lymphocytes (CTLs), but the same cell population may cause severe graft-versus-host disease. One strategy to suppress harmful CTL activity is to incorporate a suicide gene into the donor lymphocytes prior to infusion, and to destroy these cells when they aggressively attack nonmalignant host tissues. In this study, we investigated the feasibility of using a Fas-estrogen receptor fusion protein (MfasER) to control T cell-mediated cytotoxicity, based on our previous finding that the chimera transmits a Fas-mediated death signal through activation by estrogen binding. A murine CTL line CTLL-2 was transfected with a vector encoding MfasER, and the growth, viability and cytotoxic activity of the transfected cells (CTLL/MfasER) were analyzed. The expression of apoptosis-related proteins such as Fas ligand and perforin was also investigated. In the absence of estrogen, CTLL/MfasER showed similar growth to parental CTLL-2, and the killing activity was preserved. Addition of 10 (-7) M estrogen induced a rapid apoptosis of CTLL/MfasER, and the cytotoxicity was severely impaired. A decrease of Fas ligand and perforin in the estrogen-treated CTLL/MfasER was seen in an immunoblot analysis. These functional and biochemical analyses showed that the estrogen-inducible apoptosis in MfasER-expressing CTLs rapidly terminated their target cell killing. The feasibility of using the MfasER-estrogen system to control graft-versus-host disease was demonstrated.
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PMID:Reduction of CTLL-2 cytotoxicity by induction of apoptosis with a Fas-estrogen receptor chimera. 1284 75

Mature donor T cells cause graft-versus-host disease (GVHD), but they are also the main mediators of the beneficial graft-versus-tumor (GVT) activity of allogeneic bone marrow transplantation. Suppression of GVHD with maintenance of GVT activity is a desirable outcome for clinical transplantation. We have previously shown that donor-derived CD4+CD25+ regulatory T cells inhibit lethal GVHD after allogeneic bone marrow transplantation across major histocompatibility complex (MHC) class I and II barriers in mice. Here we demonstrate that in host mice with leukemia and lymphoma, CD4+CD25+ regulatory T cells suppress the early expansion of alloreactive donor T cells, their interleukin-2-receptor (IL-2R) alpha-chain expression and their capacity to induce GVHD without abrogating their GVT effector function, mediated primarily by the perforin lysis pathway. Thus, CD4+CD25+ T cells are potent regulatory cells that can separate GVHD from GVT activity mediated by conventional donor T cells.
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PMID:CD4+CD25+ regulatory T cells preserve graft-versus-tumor activity while inhibiting graft-versus-host disease after bone marrow transplantation. 1294 24


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