Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0018133 (graft-versus-host disease)
 18,032 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The administration of cyclosporin A (CsA) after autologous stem cell transplantation (SCT) paradoxically elicits a systemic autoimmune syndrome that resembles graft-versus-host disease (GVHD); this is termed autologous GVHD (autoGVHD). Although dominated by activated CD8+ cytotoxic T lymphocytes, the complex cellular reaction also includes CD4+ T cells and involves multiple effector mechanisms. To determine the temporal development and relative importance of these mechanisms in autoGVHD, perforin/granzyme, Fas ligand (FasL), interferon-gamma (IFN-gamma), tumor necrosis factor (TNF)-alpha, and interleukin-18 gene expression in peripheral blood mononuclear cells was examined in 36 patients treated with CsA after SCT. Quantitative real-time polymerase chain reaction analysis revealed that perforin/granzyme B, TNF-alpha, and interleukin-18 messenger RNA (mRNA) levels in peripheral blood mononuclear cells from patients in whom autoGVHD developed were markedly higher (and temporally associated with the onset of autoaggression) compared with the levels detected in healthy individuals and in control, non-CsA-treated SCT patients. It is interesting to note that patients in whom autoGVHD did not develop also demonstrated increased mRNA levels for these cytokines: however, expression was substantially lower compared with that in patients with autoGVHD. It is important to note that IFN-gamma mRNA levels were selectively increased in CD8+ cells only from patients in whom autoGVHD developed. The development of autocytolytic T cells in autoGVHD correlated with increased expression of perforin, IFN-gamma, and TNF-alpha mRNA. Furthermore, enhanced autoreactive T-cell activity and the induction of autoGVHD was also concordant with perforin and TNF-alpha mRNA upregulation in CD4+ cells. Surprisingly, FasL mRNA levels were significantly decreased, with a progressive loss of FasL mRNA expression as autocytolytic activity increased. These findings suggest that IFN-gamma/perforin-based CD8+ cytotoxic T lymphocytes seem to play a dominant role in autoGVHD and that TNF-alpha/perforin-based CD4+ cells may amplify this autoaggressive syndrome. The FasL pathway may play an important role in the regulation of this immune syndrome.
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PMID:Cytolytic effector mechanisms and gene expression in autologous graft-versus-host disease: distinct roles of perforin and Fas ligand. 1499 81

To investigate the value of apoptosis of the allo-antigen specific T cells induced by Fas/FasL pathway in preventing graft-versus-host disease (GVHD), the CD34+ cells transfected with FasL or not, used as stimulus cells, were mixed with allo-antigen specific T lymphocytes in presence or absence of IFN-gamma and IL-2. After 5 days, apoptosis of T cells was detected by TdT nick end mediated dUTP labeling (TUNEL) and flow cytometry (FCM). The affects of these two cytokines on CD34+ cells in the graft were also compared. The ratio of apoptosis of T cells was 12.1+/-1.5% when CD34+ cells transfected with FasL was used as stimulus cells, much higher than that of CD34+ cells non-transfected (3.2+/-1.1%, P<0.01). And in presence of IFN-gamma or IL-2, the ratio reached 20.1+/-2.3%, 17.6+/-1.3% respectively (P<0.01). However, IFN-gamma up-regulated Fas expression of CD34+ cells and increased the sensibility of CD34+ cells to soluble FasL (sFasL); IL-2 showed no such effect. It is possible to induce apoptosis of the allo-antigen specific T cells of grafts activated by allo-antigen by exogenous Fas ligand expressed on recipient cells and this might provide a new approach for preventing GVHD and IL-2 may be more suitable for clinical application.
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PMID:Selective depletion of the allo-antigen specific T cells by Fas/FasL pathway by cytokine IFN-gamma and IL-2. 1501 31

Although IFN-gamma is the archetypal Th1 cytokine, its role in CTL maturation is uncertain. We used an in vivo mouse model of CTL development, parent-into-F(1) acute graft-vs-host disease (AGVHD), to evaluate this issue. In AGVHD, transfer of naive parental T cells into F(1) hosts stimulates the development of allospecific CTL effectors that eliminate host lymphocytes, particularly B cells. Complete elimination of IFN-gamma, using IFN-gamma-deficient donors and administering anti-IFN-gamma mAb, suppressed B cell elimination, down-regulated TNF-alpha production, and enhanced Th2 cytokine production, but did not allow the B cell expansion characteristic of chronic GVHD (CGVHD). Because complete CTL inhibition results in full-blown CGVHD that is IFN-gamma independent, these observations indicate that IFN-gamma elimination only partially blocks CTL development. IFN-gamma elimination did not inhibit donor T cell engraftment or activation in the AGVHD model, but almost completely blocked Fas/Fas ligand (FasL) gene expression, protein up-regulation, and Fas/FasL-mediated CTL killing. In contrast, IFN-gamma elimination only partially inhibited perforin gene expression and perforin-mediated CTL activity. The contributions of IFN-gamma to CTL development were indirect, because IFN-gamma receptor-deficient donor cells differentiated normally into allospecific CTLs. Consistent with the view that the Fas/FasL and perforin pathways each mediate CTL killing in AGVHD, the absence of both perforin and IFN-gamma (perforin knockout donor cells and anti-IFN-gamma mAb) converted AGVHD to CGVHD. Thus, both IFN-gamma-dependent induction of Fas/FasL and IFN-gamma-independent induction of perforin contribute to CTL-mediated elimination of host B cells in AGVHD. Suppression of both pathways is required for typical CGVHD development.
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PMID:Differential requirement for IFN-gamma in CTL maturation in acute murine graft-versus-host disease. 1524 Jun 78

Fas ligand (FasL) and perforin pathways not only are the major mechanisms of T cell-mediated cytotoxicity but also are involved in homeostatic regulation of these T cells. In the present study, we tested whether CD8+ donor T cells that are deficient in both perforin and FasL (cytotoxic double deficient [cdd]) could induce graft-versus-host disease (GVHD) in a major histocompatibility complex class I-mismatched lethally irradiated murine model. Interestingly, recipients of cdd CD8+ T cells demonstrated significantly greater serum levels of interferon gamma and tumor necrosis factor alpha and histopathologic damage from GVHD than wild-type (wt) T cells on day 30 after allogeneic bone marrow transplantation (P<.05). Wt and either perforin-deficient or FasL-deficient CD8+ T cells expanded early after transplantation followed by a contraction phase in which the majority of expanded CD8+ T cells were eliminated. In contrast, cdd CD8+ T cells exhibited prolonged expansion and reduced apoptosis to alloantigen stimulation in vivo and in vitro. Together these results suggest that donor cdd CD8+ T cells expand continuously and cause lethal GVHD, and that both perforin and FasL are required for the contraction of allo-reactive CD8+ T cells.
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PMID:Both perforin and Fas ligand are required for the regulation of alloreactive CD8+ T cells during acute graft-versus-host disease. 1546 30

In order to explore a new special and effective way to prevent graft versus host disease (GVHD) after allogenic bone marrow transplantation (allo-BMT), the stem cell antigen-1 (Sca-1) + early hematopoietic cells (EHC) from BALB/c mouse (H-2d) were introduced with exogenous mouse Fas ligand (mFasL) cDNA gene by the retrovirus-mediated gene transfer and expanded for one week, and then they were co-cultured with the spleen mononuclear cells (SMNC) from BAC mouse (H-2dxb) as one way mixed lymphocyte reaction (OWMLR). The cytotoxicity of treated BAC mouse SMNC against Na2 51CrO4 labeling SMNC from BALB/c mouse was observed. The bone marrow mononuclear cells (BMMNC) from BAC mouse treated by the above methods were transplanted into lethally-irradiated congenic BALB/c mice to observe the occurrence of GVHD. The results showed that the SMNC from BAC mouse after OWMLR with exogenous mFasL cDNA gene-transduced hematopoietic cells (HC) from BALB/c mouse in a ratio of 1 to 5 exhibited an obvious inhibition of the cytotoxicity against the BALB/c mouse spleen cells at different effector/target ratios as compared to the control group (P<0.01). The grade I GVHD or no GVHD and the 80% survival rate at day 60 post-BMT were observed in the BALB/c mouse receiving BAC mouse BMMNC treated with similar way, while the grade II - III GVHD and the 20% survival rate were noted in the control group (P<0.01). It is suggested that the attenuation of GVHD in allo-BMT recipient could be successfully achieved through FasL-Fas pathway in an H-2 haplotype disparate mouse combination.
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PMID:Attenuation of GVHD for allo-bone marrow transplantation recipient by FasL-Fas pathway in an H-2 haplotype disparate mouse combination. 1558 91

The biliary epithelium provides a physical barrier to ascending infection from the gastrointestinal tract and is also involved in actively regulating the immune response to invading pathogens. Cholangiocytes secrete chemokines and express adhesion molecules that attract effector leukocytes and promote the clearance of infected cells. However in the context of transplantation these properties make cholangiocytes targets for allogeneic cytotoxic T cells, and both graft-versus-host disease and liver allograft rejection are characterized by destruction of intrahepatic bile ducts by infiltrating lymphocytes. The mechanisms of cholangiocyte killing are complex but involve activation of apoptosis by the granzyme/perforin pathway and by activation of death receptors belonging to the tumor necrosis factor (TNF) receptor superfamily, most notably Fas. Fas-dependent apoptosis is carefully regulated by cooperative interactions with other TNF receptors, particularly CD40, that act to amplify autocrine and paracrine expression of Fas ligand and Fas-mediated killing. A better understanding of the molecular control of these processes may explain why bile duct loss continues despite conventional immunosuppression in the vanishing bile duct syndromes, and lead to novel therapies aimed at switching off the chronic inflammatory response and protecting cholangiocytes from apoptosis.
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PMID:Effector mechanisms of nonsuppurative destructive cholangitis in graft-versus-host disease and allograft rejection. 1614 44

To determine the mechanisms of graft-versus-tumor (GVT) activity in the absence of graft-versus-host disease (GVHD) against a solid tumor, we established two allogeneic bone marrow transplantation models with a murine renal cell carcinoma (RENCA). The addition of 0.3 x 10(6) donor CD8(+) T cells to the allograft increased the survival of tumor-bearing mice without causing GVHD. The analysis of CD8(+) T cells deficient in cytotoxic molecules demonstrated that anti-RENCA activity is dependent on IFN-gamma and Fas ligand (FasL), but does not require soluble or membrane-bound TNF-alpha, perforin, or TRAIL. Recipients of IFN-gamma(-/-) CD8(+) T cells are unable to reject RENCA compared with recipients of wild-type CD8(+) T cells and, importantly, neither group develops severe GVHD. IFN-gamma(-/-) CD8(+) T cells derived from transplanted mice are less able to kill RENCA cells in vitro, while pretreatment of RENCA cells with IFN-gamma enhances class I and FasL expression and rescues the lytic capacity of IFN-gamma(-/-) CD8(+) T cells. These results demonstrate that the addition of low numbers of selected donor CD8(+) T cells to the allograft can mediate GVT activity without lethal GVHD against murine renal cell carcinoma, and this GVT activity is dependent on IFN-gamma and FasL.
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PMID:IFN-gamma and Fas ligand are required for graft-versus-tumor activity against renal cell carcinoma in the absence of lethal graft-versus-host disease. 1764 Oct 33

Although stem cell transplantation (SCT) is being used for hematopoietic reconstitution following high-dose chemotherapy for malignancy, it involves certain serious transplant-related complications such as graft-versus-host disease (GVHD). Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) plays important roles in regulating cell death, immune response, and inflammation. However, the role of soluble TRAIL (sTRAIL) after SCT is poorly understood. In this study, 42 patients underwent SCT; 22 patients received allogeneic SCT, while the remaining 20 received autologous SCT. In these patients, levels of sTRAIL, cytokines, and soluble factors were measured by enzyme-linked immunosorbent assay (ELISA). In addition, a basic study of the generation of endothelial cell-derived microparticle (EDMP) by TNF-alpha and soluble Fas ligand (sFasL) was conducted. sFasL and EDMP exhibited significant elevation in the early phase (2-3 weeks) after SCT. In addition, the elevation of IL-6, TNF-alpha, and sIL-2R after allogeneic SCT was observed. EDMP also exhibited changes similar to sFasL. The patients with high sTRAIL exhibited significant decrease of sFasL and EDMP as compared with those without high sTRAIL. TNF-alpha and sFasL induced an increase in procoagulant and apoptotic markers in endothelial cells, and EDMP shedding was observed. Furthermore, sTRAIL inhibited the EDMP elevation caused by TNF-alpha and sFasL. The apoptotic markers such as sFasL and sTRAIL exhibited particular changes after SCT. Our results suggest that sTRAIL generation after allogeneic SCT relates to the prevention of GVHD.
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PMID:Role of soluble tumor necrosis factor-related apoptosis-inducing ligand concentrations after stem cell transplantation. 1800 54

Because ex vivo rapamycin generates murine Th2 cells that prevent Graft-versus-host disease more potently than control Th2 cells, we hypothesized that rapamycin would generate Th2/Tc2 cells (Th2/Tc2.R cells) that abrogate fully MHC-disparate hemopoietic stem cell rejection more effectively than control Th2/Tc2 cells. In a B6-into-BALB/c graft rejection model, donor Th2/Tc2.R cells were indeed enriched in their capacity to prevent rejection; importantly, highly purified CD4+ Th2.R cells were also highly efficacious for preventing rejection. Rapamycin-generated Th2/Tc2 cells were less likely to die after adoptive transfer, accumulated in vivo at advanced proliferative cycles, and were present in 10-fold higher numbers than control Th2/Tc2 cells. Th2.R cells had a multifaceted, apoptosis-resistant phenotype, including: 1) reduced apoptosis after staurosporine addition, serum starvation, or CD3/CD28 costimulation; 2) reduced activation of caspases 3 and 9; and 3) increased anti-apoptotic Bcl-xL expression and reduced proapoptotic Bim and Bid expression. Using host-versus-graft reactivity as an immune correlate of graft rejection, we found that the in vivo efficacy of Th2/Tc2.R cells 1) did not require Th2/Tc2.R cell expression of IL-4, IL-10, perforin, or Fas ligand; 2) could not be reversed by IL-2, IL-7, or IL-15 posttransplant therapy; and 3) was intact after therapy with Th2.R cells relatively devoid of Foxp3 expression. We conclude that ex vivo rapamycin generates Th2 cells that are resistant to apoptosis, persist in vivo, and effectively prevent rejection by a mechanism that may be distinct from previously described graft-facilitating T cells.
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PMID:Ex vivo rapamycin generates apoptosis-resistant donor Th2 cells that persist in vivo and prevent hemopoietic stem cell graft rejection. 1809 8

Although stem cell transplantation (SCT) is being used for hematopoietic reconstitution following high-dose chemotherapy for malignancy, it involves certain serious transplant-related complications such as graft-versus-host disease (GVHD). Angiopoietins play important roles in angiogenesis. However, the role of angiopoietins after SCT is poorly understood. In this study, 52 patients underwent SCT; 26 patients received allogeneic SCT, while the remaining 26 received autologous SCT. In 48 of 52 patients, levels of angiopoietins, cytokines, and soluble factors were measured by enzyme-linked immunosorbent assay. Soluble Fas ligand (sFasL) and endothelial cell-derived microparticle (EDMP) exhibited significant elevation in the early phase (2-3 weeks) after SCT. In addition, the elevation of interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and sIL-2 receptor (sIL-2R), which are GVHD markers after allogeneic SCT was observed. The level of angiopoietin (Ang)-2 in allogeneic SCT continued to increase for up to 4 weeks, although the level of Ang-1 did not show significant changes. The patients with high Ang-2 exhibited significant increase of sFasL and EDMP compared with those with low Ang-2. In addition, the patients with high-grade GVHD exhibited a significant increase in Ang-2 compared to patients with low-grade GVHD. In the in vitro experiment using endothelial cells, the suppressive effect of Ang-1 on EDMP generation by TNF-alpha was partially inhibited by the addition of Ang-2. Furthermore, multivariate regression analysis showed that EDMP and sFasL were significant factors in Ang-2 elevation. Our results suggest that Ang-2 generation after allogeneic SCT relates to GVHD.
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PMID:Evaluation of angiopoietins and cell-derived microparticles after stem cell transplantation. 1854 Nov 95


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