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)

Research into the pathogenesis of psoriasis has been hampered by the lack of an animal disease resembling this common human skin disorder. Over the past few years, however, various rodent models that mirror aspects of the psoriatic phenotype and pathogenesis have become available. Here, the most prominent models are compared with human psoriasis and potential uses for psoriasis research are reviewed. Asebia (ab), flaky skin (fsn), and chronic proliferative dermatitis (cpd) are spontaneous mouse mutations with psoriasiform skin alterations of unclear pathogenesis. Transgenic mice with cutaneous overexpression of cytokines, such as interferon-gamma, interleukin-1alpha, keratinocyte growth factor, transforming growth factor-alpha, interferon-6, vascular endothelial growth factor, or bone morphogenic protein-6, are valuable tools for studying in vivo effects of individual cytokines in the pathogenesis of psoriasiform features. Psoriasiform lesions also were seen in beta2-integrin hypomorphic mice backcrossed to the PL/J strain and in beta1-integrin transgenic mice. A T cell-based immunopathogenesis of psoriasiform features was shown in a form of graft-versus-host disease in scid/scid mice reconstituted with CD4+/CD45RB(hi) T lymphocytes as well as in HLA-B27/hbeta2m transgenic rats, demonstrating that dysregulated T cells can induce psoriasiform skin alterations without a primary epithelial abnormality. Finally, xenotransplantation models using human skin grafted on to immunodeficient mice are attractive, as different cell types and some environmental factors leading to psoriasiform features may be studied in human tissue. Overall, although there is no animal model imitating psoriasis completely, many aspects of this common human skin disorder are mirrored in the currently available models and psoriatic plaques can be created in xenotransplantation models.
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PMID:Animal models of psoriasis - what can we learn from them? 1046 48

The major obstacles to successful outcome after allogeneic bone marrow transplantation (BMT) for leukemia remain graft-versus-host disease (GVHD) and leukemic relapse. Improved survival after BMT therefore requires more effective GVHD prophylaxis that does not impair graft-versus-leukemia (GVL) effects. We studied the administration of human recombinant keratinocyte growth factor (KGF) in a well- characterized murine BMT model for its effects on GVHD. KGF administration from day -3 to +7 significantly reduced GVHD mortality and the severity of GVHD in the gastrointestinal (GI) tract, reducing serum lipopolysaccharide (LPS) and tumor necrosis factor (TNF)alpha levels, but preserving donor T-cell responses (cytotoxic T lymphocyte [CTL] activity, proliferation, and interleukin [IL]-2 production) to host antigens. When mice received lethal doses of P815 leukemia cells at the time of BMT, KGF treatment significantly decreased acute GVHD compared with control-treated allogeneic mice and resulted in a significantly improved leukemia-free survival (42% v 4%, P <.001). KGF administration thus offers a novel approach to the separation of GVL effects from GVHD.
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PMID:Keratinocyte growth factor separates graft-versus-leukemia effects from graft-versus-host disease. 1039 51

Acute graft-versus-host disease (GVHD), the major complication of allogeneic bone marrow transplantation (BMT), limits the application of this curative but toxic therapy. Studies of inflammatory pathways involved in GVHD in animals have shown that the gastrointestinal (GI) tract plays a major role in the amplification of systemic disease. Damage to the GI tract increases the translocation of inflammatory stimuli such as endotoxin, which promotes further inflammation and additional GI tract damage. The GI tract is therefore critical to the propagation of the "cytokine storm" characteristic of acute GVHD. Experimental approaches to the prevention of GVHD include reducing the damage to the GI tract by fortification of the GI mucosal barrier through novel "cytokine shields" such as IL-11 or keratinocyte growth factor. Such strategies have reduced GVHD while preserving a graft-versus-leukemia effect in animal models, and they now deserve formal testing in carefully designed clinical trials. (Blood. 2000;95:2754-2759)
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PMID:The primacy of the gastrointestinal tract as a target organ of acute graft-versus-host disease: rationale for the use of cytokine shields in allogeneic bone marrow transplantation. 1077 17

We have previously shown that pretreatment of mice with keratinocyte growth factor (KGF), an epithelial tissue repair factor, can ameliorate graft-versus-host disease (GVHD) after intensive chemoradiotherapeutic conditioning and allogeneic bone marrow transplantation (BMT). To determine whether this effect was dependent on a KGF-mediated mechanism affecting repair of conditioning-induced epithelial cell injury, we studied GVHD in the absence of conditioning using BALB/c severe combined immune-deficient (SCID) recipients given C57BL/6 T cells. KGF (5 mg/kg per day, subcutaneously) given either before or after T-cell transfer enhanced body weights and extended survival. KGF-treated recipients had elevated serum levels of the Th2 cytokine interleukin 13 (IL-13) on day 6 after T-cell transfer concomitant with reduced levels of the inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interferon gamma (IFN-gamma). A 3-day KGF pretreatment also depressed the secondary in vitro mixed lymphocyte response (MLR) of C57BL/6 splenocytes taken 7 days after in vivo alloimmunization with irradiated BALB/c spleen cells. To determine whether KGF would inhibit host-antidonor-mediated BM rejection, pan-T-cell-depleted BALB/c BM cells were infused into sublethally irradiated C57BL/6 mice and administered KGF either before or before and after BMT. Surprisingly, all KGF schedules tested actually resulted in enhanced alloengraftment. The presence of KGF receptor on donor antihost alloreactive T cells could not be detected by binding studies with radiolabeled KGF, reverse transcriptase-polymerase chain reaction, and Western blotting. Therefore, the mechanism of action of KGF on inhibiting T-cell-mediated immune effects may not be due to a direct effect of KGF on T cells. These studies demonstrate that KGF, by mechanisms independent of repair of conditioning-induced injury, has great potential as an anti-GVHD therapeutic agent with the added benefit of inhibiting the rejection of pan-T-cell-depleted donor BM allografts. (Blood. 2000;96:4350-4356)
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PMID:Keratinocyte growth factor facilitates alloengraftment and ameliorates graft-versus-host disease in mice by a mechanism independent of repair of conditioning-induced tissue injury. 1111 Jul 12

Acute and chronic graft versus host disease (GVHD) remain the major barriers to successful hematopoietic cell transplantation. The induction of GVHD may be divided into three phases: recipient conditioning;donor T-cell activation; andeffector cells mediating GVHD. This review examines GVHD prevention and treatment using this conceptual model as framework. The various pharmacological agents discussed impact on different phases of the GVHD cascade. For example, keratinocyte growth factor and interleukin (IL)-11 are cytokines that may be useful in disrupting phase I of the GVHD cascade by blocking gastrointestinal tract damage, and lowering serum levels of lipopolysaccharide and tumour necrosis factor (TNF)-alpha. Cyclosporin, tacrolimus (FK-506) and sirolimus (rapamycin) are some of the main agents that disrupt phase II (donor T-cell activation). Mycophenolate mofetil and tresperimus probably act on this phase as well. Other novel drugs that affect phase II are tolerance-induction agents such as CTLA-4 and anti-CD40-ligand monoclonal antibodies, and preliminary results using CTLA-4 monoclonal antibody in GVHD prevention are encouraging. Examples of agents that disrupt phase III are the IL-2 receptor antagonist daclizumab and the anti-TNFalpha monoclonal antibody infliximab. These anti-cytokine antibodies have shown promising results in early studies. The most effective approach to GVHD prevention will probably be a combination regimen where the three phases of the GVHD cascade are disrupted. Once GVHD has occurred, all three phases of the cascade are activated. Developments of combination therapy for treatment of both acute and chronic GVHD are likely to yield better results than monotherapy. The numerous new treatment modalities presented should improve the outlook for patients with acute and chronic GVHD.
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PMID:Novel pharmacotherapeutic approaches to prevention and treatment of GVHD. 1192 36

Thymus-dependent reconstitution of the peripheral T-cell compartment is critical for the successful outcome of bone marrow transplantation. However, graft-versus-host disease (GVHD) affects thymic stromal function and thus prevents normal T-cell maturation and selection. To determine whether cytoprotection of thymic epithelial cells (TECs) by keratinocyte growth factor (KGF) averts GVHD-related injury to the thymus, a nonirradiated murine parent-->F(1) transplantation model was investigated. Administration of KGF between days -3 and +3 of GVHD induction preserved normal thymic size, cellularity, and thymocyte phenotype when measured 2 weeks after transplantation and compared with saline-treated parent-->F(1) mice that received allogeneic transplants. Moreover, the characteristic GVHD-induced impairment in cell cycle progression of pro- and pre-T cells was prevented by KGF. However, the normal phenotypic and functional status of the thymus did not correlate with the higher number of GVHD-inducing mature donor T cells in thymi of KGF-treated mice. Importantly, extensive analysis of the different TEC populations within the thymic cortex and medulla revealed an almost normal stromal architecture and composition in GVHD mice treated with KGF. These observations are likely to reflect an indirect effect of KGF on thymopoiesis as KGF-receptor expression was demonstrated to be restricted to TECs. Thus, pharmacologic doses of KGF appear to exert a potent effect on TEC function, which in turn allows for normal T lymphopoiesis to occur during acute GVHD.
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PMID:Keratinocyte growth factor preserves normal thymopoiesis and thymic microenvironment during experimental graft-versus-host disease. 1209 65

Acute graft-versus-host disease (GVHD) and chronic GVHD remain the major barriers to successful haematopoietic cell transplantation. The induction of GVHD may be divided into three phases: recipient conditioning, donor T cell activation and effector cells mediating GVHD. This review examines GVHD prevention and treatment using this conceptual model as framework. The various pharmacological agents discussed impact on different phases of the GVHD cascade. For example, keratinocyte growth factor and IL-11 are cytokines that may be useful in disrupting Phase I of the GVHD cascade by blocking gastrointestinal tract damage and lowering serum levels of lipopolysaccharide and TNF-alpha. Cyclosporin, FK506 and sirolimus are some of the main agents that disrupt Phase II (donor T cell activation). Mycophenolate mofetil likely acts on this phase as well. Other novel drugs that affect Phase II are tolerance-induction agents such as cytotoxic T lymphocyte antigen (CTLA)-4 Ig and anti-CD40 ligand, and preliminary results using CTLA-4 Ig in GVHD prevention are encouraging. Two exciting agents that appear to affect only activated lymphocytes are ABX-CBL and visilizumab. Examples of agents that disrupt Phase III are the IL-2 receptor antagonist daclizumab and the anti-TNF-alpha monoclonal antibody infliximab. These anticytokine antibodies have shown promising results in early studies. The most effective approach to GVHD prevention will likely be a combination regimen where the three phases of the GVHD cascade are disrupted. Once GVHD has occurred, all three phases of the cascade are activated. Developments of combination therapy for treatment of both acute and chronic GVHD will likely yield better results than monotherapy. The numerous new treatment modalities presented should improve the outlook for acute and chronic GVHD.
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PMID:Novel therapeutics for the treatment of graft-versus-host disease. 1222 48

Acute graft-versus-host disease (aGVHD) is the major complication of allogeneic stem cell transplantation (allo-HSCT), significantly limits the application of the therapy. Current evidence suggests that dysregulated cytokine production is responsible for many manifestations of aGVHD. The mechanisms have been most clearly delineated in mouse models, detailed analysis of human tissue is required. Monitoring serum levels of cytokine sIL-2R, TNF-alpha and IFN-gamma after transplantation or cytokine gene expression before transplantation can predict prognossis of aGVHD. GVHD have graft-versus-leukemia (GVL) effect, and GVL can be seperated from GVHD. IL-2, IL-12, IL-11, KGF and G-CSF could possess the roles of reducing GVHD while preserving GVL.
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PMID:[Roles of Cytokines in Acute Graft-Versus-Host Disease] 1257 74

Graft-versus-host disease (GVHD) is the principal complication after allogeneic bone marrow transplantation (BMT). Reductions in systemic GVHD are frequently associated with a corresponding diminishment of the graft-versus-leukemia (GVL) response. In this study, we tested the effects of a novel recombinant human keratinocyte growth factor, repifermin (keratinocyte growth factor-2), on the induction of GVHD in a well-defined murine BMT model (B6 --> B6D2F1). Administration of repifermin (5 mg/kg/d) to allogeneic BMT recipients resulted in a significant decrease in both systemic GVHD and target organ histopathology. Repifermin treatment also reduced serum levels of tumor necrosis factor alpha and lipopolysaccharide compared with control mice. In contrast, repifermin did not affect T-cell proliferation, cytokine production, or cytotoxic responses to host antigens. When 2000 host-derived P815 (H-2(d)) leukemia cells were added to the bone marrow inoculum, repifermin preserved GVL effects and resulted in significantly delayed mortality compared with control-treated allogeneic BMT recipients. Collectively, these data suggest that repifermin administration may represent a novel strategy to separate the toxicity of GVHD from the beneficial GVL effects after allogeneic BMT.
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PMID:Repifermin (keratinocyte growth factor-2) reduces the severity of graft-versus-host disease while preserving a graft-versus-leukemia effect. 1450 61

We studied the effect of rHuKGF on acute, lethal graft- vs.-host disease (GVHD) in the C57BL/6-->(C57BL/6 X DBA/2)F(1)-hybrid model. rHuKGF-treated recipients did not develop intestinal GVHD despite elevated levels of intestinal NO and TNF alpha, did not develop endotoxemia, and did not die. LPS augmented serum TNF alpha release and intestinal NO production, but did not induce intestinal epithelial cell apoptosis, a phenomenon associated with acute GVHD. These data suggest that KGF prevents the development of acute lethal GVHD by protecting epithelial cell injury mediated by TNF-alpha, NO, and other potential cytotoxic factors. We noted a moderate reduction in intestinal KGFR mRNA expression in untreated GVH mice on day 8, when IFN-gamma mRNA levels were highest. This reduction in KGFR mRNA levels was not seen in recipients of IFN-gamma gene knockout grafts, suggesting that IFN-gamma may be involved in reducing KGFR mRNA expression in the intestine. A similar reduction in intestinal KGFR mRNA expression was also seen in rHuKGF-treated recipients, suggesting that rHuKGF does not mediate its protective effect by maintaining KGFR at control levels. KGF-treatment also redirected the cytokine response in acute GVH mice from Th1 to a mixed pattern of both Th1 and Th2 cytokines. This was associated with histopathologic changes resembling chronic GVHD.
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PMID:Effect of recombinant human keratinocyte growth factor (rHuKGF) on the immunopathogenesis of intestinal graft-vs.-host disease induced without a preconditioning regimen. 1502 87


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