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)

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

Syngeneic graft-versus-host disease (SGVHD) develops following lethal irradiation, reconstitution with syngeneic bone marrow, and treatment with a short course of cyclosporin A (CsA) therapy. The disease is characterized by the development of a T helper cell type 1-like cytokine response [interleukin (IL)-12, interferon-gamma (IFN-gamma), and tumor necrosis factor alpha], and macrophage activation is central to development of the syndrome. It has been shown that nitric oxide (NO) participates significantly in the development of allogeneic GVHD. Studies were initiated to determine if NO participates in the pathology associated with SGVHD. Significant increases in inducible NO synthase (iNOS) mRNA and circulating NO were found in the tissues of SGVHD versus control animals. Treatment of SGVHD animals with the iNOS inhibitor aminoguanidine (AG) reversed the pathology associated with this disease. Furthermore, AG treatment reduced the production of IL-12 and IFN-gamma mRNA in the colons of CsA-treated mice. These studies demonstrate that NO participates in the pathological processes that are associated with the development of murine SGVHD.
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PMID:Nitric oxide participates in the intestinal pathology associated with murine syngeneic graft-versus-host disease. 1237 46

Preconditioning with the nonmyeloablative regimen total lymphoid irradiation (TLI) before hematopoietic cell transplantation facilitates the establishment of mixed chimerism and protects against graft-versus-host disease. We reported that the development of mixed chimerism requires interleukin (IL)-4 and is associated with increased host anti-donor TH2 cells, but the effect of TLI on the differentiation of immunocompetent donor cells has not been investigated. To examine the extent to which TLI preconditioning influences donor T cells, we measured responses of transgenic CD4+cells specific for ovalbumin peptide (OVA-Tg) following in vivo and in vitro antigen stimulation in a TLI-preconditioned environment. OVA-Tg cells that were adoptively transferred into TLI-preconditioned mice that express cross-reactive antigens produced more IL-4 and less interferon-gamma and IL-2 than controls when stimulated with OVA peptide one week later. OVA-Tg primed in vitro with spleen from TLI-preconditioned mice generated more TH2 and fewer TH1 cells when stimulated in recall enzyme-linked immunosorbent spot (ELISPOT) assays with OVA peptide. Naive OVA-Tg up-regulated CD69 and CD25 normally following stimulation with OVA peptide in the presence of spleen from TLI-preconditioned mice, but proliferated less and secreted less IL-2 than controls. Surprisingly, naive OVA-Tg secreted IL-4 in primary cultures that were stimulated with OVA peptide in the presence of spleen from TLI-preconditioned mice. This response depends on CD4+cells from TLI-spleen, which constitutively produce IL-4 and are composed primarily of CD4+-natural killer T (TNK) cells. Thus, TLI preconditioning enriches for IL-4-secreting and TNK-like CD4+cells that may function in the protection from graft-versus-host disease by redirecting the differentiation of immunocompetent donor CD4+cells toward TH2 and away from pathogenic TH1 cells.
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PMID:Total lymphoid irradiation nonmyeloablative preconditioning enriches for IL-4-producing CD4+-TNK cells and skews differentiation of immunocompetent donor CD4+ cells. 1240 8

We investigated whether pretreatment with eicosapentaenoic acid, an inhibitor of leukotriene (LT) B4, could ameliorate acute colonic graft-versus-host disease (GVHD) after bone marrow transplantation (BMT). Seventeen patients undergoing unrelated BMT were divided into two groups, with eight patients receiving eicosapentaenoic acid and nine not receiving it. The grade of GVHD after transplantation was compared with that estimated from the pretransplantation LTB4 level. The levels of LTB4 and several cytokines were also monitored. The actual grade of GVHD was lower than that estimated from LTB4 levels in three of the eight patients from the treated group, and there was a significant difference between the treated and untreated groups (p < 0.05, chi 2 test). The levels of LTB4, tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) were all significantly lower in the treated group (p < 0.05, Student's t-test). These findings suggest that eicosapentaenoic acid may ameliorate acute colonic GVHD when administered from before BMT.
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PMID:Oral eicosapentaenoic acid for acute colonic graft-versus-host disease after bone marrow transplantation. 1251 29

Indoleamine 2,3-dioxygenase (IDO) is an interferon-gamma (IFN-gamma)-induced enzyme, which is suggested to play an important role in the prevention of allogeneic fetal rejection. IDO effects the suppression of T-cell activity by catabolizing the essential amino acid l-tryptophan. We studied IDO expression by reverse transcription polymerase chain reaction (RT-PCR) in dendritic cells and by real-time RT-PCR in monocytes of patients undergoing allogeneic transplantation for leukaemia, who developed acute graft-versus-host disease (aGvHD), and compared the IDO expression with that of pregnant women and healthy volunteers. A spontaneous IDO expression was detected in the monocytes of 20 pregnant women with an IDO/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) ratio at a median of 1.0%, whereas none of 15 healthy volunteers or patients after allogeneic transplant had any detectable spontaneous IDO expression. The IDO expression increased by in vitro IFN-gamma stimulation in pregnant women (median 116%), healthy volunteers (median 11.7%) and patients with a low-grade aGvHD (grades 0-II) 28 days after transplant (median 433%) but not in patients with a severe aGvHD (grades III-IV) (median 0%), which was highly significant (P < 0.01). IDO expression was also measured in dendritic cells by qualitative RT-PCR, where a spontaneous IDO expression was detected in 16 of 31 (52%) pregnant women versus none of 17 healthy volunteers and none of 62 studied patients after transplant. IFN-gamma-induced IDO expression was detected in all pregnant women, all volunteers and 47 of 49 (96%) patients with a low-grade aGvHD (grades 0-II) after transplant, whereas only in two of 13 (16%) patients with aGvHD grade III-IV was IFN-gamma-induced IDO expression observed. These data suggest that IDO expression might be involved in the development of allogeneic immune tolerance.
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PMID:Indoleamine 2,3-dioxygenase expression in patients with acute graft-versus-host disease after allogeneic stem cell transplantation and in pregnant women: association with the induction of allogeneic immune tolerance? 1258 66

The role of T cells in eradicating leukemic cells has been well demonstrated for chronic myeloid leukemia (CML). Type 1 (T1) T-cell cytokines play a major role in this antileukemic immune effect. Studies in cancer patients have demonstrated a decreased T1 cytokine production, measured by enzyme-linked immunosorbent assay (ELISA), in cultures of peripheral blood mononuclear cells. This observation of malignancy-related suppressed T1 cytokines also occurs in untreated chronic-phase (CP) CML, raising the question of the influence of different CML treatment regimens on this immunosuppression. Intracellular flow cytometry (ICF) has facilitated the evaluation of cytokines on a single-cell level. This study analyzed T1 (interferon-gamma) cytokine production in purified peripheral blood T cells by ICF, comparing different therapy approaches for CML. Twenty-one newly diagnosed CP CML patients were compared with 24 patients treated with interferon-alpha (IFN-alpha) and to 30 allogeneic bone marrow transplant (BMT) recipients (BCR-ABL negative by reverse-transcriptase polymerase chain reaction, and free of, or having only limited graft-versus-host disease at the time of study). Thirty-seven healthy controls were included. Our results showed a significantly decreased T-cell IFN-gamma synthesis in CP CML patients in relation to healthy controls (P = 0.0007). Treatment with IFN-alpha resulted in a shift from immunosuppression--documented for the group of untreated patients--to immunopotentiation, with an increase of T-cell IFN-gamma production (P = 0.0266). Notably, BMT enhanced IFN-gamma production of T cells to a level not only exceeding untreated patients (P < 0.0001) but also healthy volunteers (P < 0.0001). The observation of T1 cytokine up-regulation with IFN-alpha therapy indicates that enhanced T-cell function may be achievable in patients with CML, even in the absence of an allo-response.
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PMID:Intracellular cytokine analysis of interferon-gamma in T cells of patients with chronic myeloid leukemia. 1260 98

A murine model of minor histocompatibility antigen (miHCag)-mismatched bone marrow transplantation (BMT) was used to study the development of immunoregulatory cells in the posttransplantation period and their possible involvement in the dissociated graft-versus-host (GVH) and graft-versus-leukemia (GVL) reactivity of posttransplantation donor lymphocyte infusions (DLIs). DLI, applied immediately after BMT, induced GVH disease (GVHD), but when DLI was delayed for 3 weeks, GVHD was avoided while a distinct GVL response was allowed to develop. A population of Mac1+Ly6-G+Ly6-C+ immature myeloid cells, found in small numbers in normal mice, strongly expanded in spleens of chimeras, reaching a maximum level at week 3 and returning to base level by week 12. Upon isolation, these cells exhibited interferon-gamma (IFN-gamma)-dependent, nitric oxide (NO)-mediated suppressor activity toward in vitro alloresponses, suggesting that, after in vivo DLI, they are activated by IFN-gamma to produce NO and suppress GVH reactivity. Because not only alloactivated T-cell proliferation but also leukemia cell growth was found susceptible to inhibition by exogenous NO, in vivo activation of these cells after DLI may explain the occurrence of a GVL effect despite suppression of GVHD. This suggested sequence of events was supported by the finding that the ex vivo antihost proliferative response of spleen cells, recovered shortly after in vivo DLI, was characterized by strong mRNA production of the monokines interleukin-1 (IL-1), IL-6, and tumor necrosis factor-alpha (TNF-alpha) and of inducible nitric oxide synthase (iNOS). Our data suggest that transiently expanding Mac1+Ly6-G+Ly6-C+ immature myeloid cells (probably as a result of extramedullary myelopoiesis) may play a role in controlling GVH while promoting GVL reactivity of DLI after allogeneic BMT.
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PMID:Transient expansion of Mac1+Ly6-G+Ly6-C+ early myeloid cells with suppressor activity in spleens of murine radiation marrow chimeras: possible implications for the graft-versus-host and graft-versus-leukemia reactivity of donor lymphocyte infusions. 1267 88

Poor immune reconstitution after haploidentical stem cell transplantation results in a high mortality from viral infections and relapse. One approach to overcome this problem is to selectively deplete the graft of alloreactive cells using an immunotoxin directed against the activation marker CD25. However, the degree of depletion of alloreactive cells is variable following stimulation with recipient peripheral blood mononuclear cells (PBMCs), and this can result in graft versus host disease (GVHD). We have refined this approach using recipient Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) as stimulators to activate donor alloreactive T cells. Our studies demonstrate that allodepletion with an anti-CD25 immunotoxin following stimulation with HLA-mismatched host LCLs more consistently depleted in vitro alloreactivity than stimulation with host PBMCs, as assessed in primary mixed lymphocyte reactions (MLRs). Allodepletion using this approach specifically abrogates cytotoxic T-cell responses against host LCLs. In interferon-gamma (IFN-gamma) enzyme-linked immunospot (ELISPOT) assays, antiviral responses to adenovirus and cytomegalovirus (CMV) were preserved following allodepletion. Likewise, using HLA-A2-pp65 tetramers, we have shown that the frequency of CMV-specific T cells is unaffected by allodepletion. Moreover, the donor anti-EBV response is partially retained by recognition of EBV antigens through the nonshared haplotype. Finally, we studied whether allodepletion affects the response to candidate tumor antigens in myeloid malignancies. Using HLA-A2-PR1 tetramer analysis, we found that the frequency of T cells recognizing the PR1 epitope of proteinase 3 was not significantly different in allodepleted and unmanipulated PBMCs from patients with chronic myeloid leukemia (CML) undergoing transplantation. Based on these data, we have embarked on a phase 1 clinical trial of addback of allo-LCL-depleted donor T cells in the haplo-identical setting.
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PMID:Selective depletion of donor alloreactive T cells without loss of antiviral or antileukemic responses. 1276 37

Some patients lose chimerism following nonmyeloablative hematopoietic cell transplantation (HCT), yet, surprisingly, enjoy sustained tumor remissions. We hypothesized that host-versus-graft (HVG) alloresponses might induce antitumor effects against recipient tumors. We explored this question in mice by administering recipient leukocyte infusions (RLIs) to mixed chimeras established with nonmyeloablative conditioning. Mixed chimeras were prepared in the B10.A (H2a)-->B6 (H2b) strain combination using depleting anti-T-cell monoclonal antibodies (mAbs), cyclophosphamide, and thymic irradiation. B6 myeloid leukemia cells (MMB3.19) were administered 7 days following donor lymphocyte infusion (DLI) or RLI on day 35. Conversion to full donor chimerism occurred without graft-versus-host disease (GVHD) following DLI, whereas RLI led to loss of chimerism. Both RLI and DLI significantly delayed tumor mortality. In another strain combination (B10.BR [H2k]-->BALB/c [H2d]), RLI-induced or spontaneous loss of chimerism was associated with antitumor effects against the host-type B-cell lymphoma A20. HCT was essential for the antitumor effect of RLI. RLI induced elevated serum interferon-gamma (IFN-gamma) levels, and recipient-derived IFN-gamma was critical for their antitumor effects. Thus, HVG reactions (spontaneous or induced by RLI) mediate antitumor effects against hematologic malignancies via a recipient-derived IFN-gamma-mediated mechanism. A novel approach to achieving anti-tumor effects without the risk of GVHD is suggested.
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PMID:Antitumor effect of donor marrow graft rejection induced by recipient leukocyte infusions in mixed chimeras prepared with nonmyeloablative conditioning: critical role for recipient-derived IFN-gamma. 1279 60

To exploit alloreactive T-cell responses known as the graft-versus-tumor effect, allogeneic hematopoietic stem cell transplantation is being explored as experimental therapy in selected solid tumors, including metastatic melanoma. However, donor T-cell responses are often delayed and associated with severe graft-versus-host disease. Posttransplant adoptive immunotherapy using tumor-specific cytotoxic T lymphocytes (CTL) of donor origin might provide immediate graft-versus-tumor effects but not graft-versus-host disease. Therefore, the aim of the current study was to define in vitro conditions for the expansion of allogeneic major histocompatibility complex-matched CTLs targeting melanoma-associated antigens (MAA). The CTLs were generated from peripheral blood mononuclear cells (PBMCs) of HLA-A*0201+ healthy donors by repetitive stimulations with HLA-A*0201-restricted MAA-derived peptides. Melanoma reactivity, as determined by lysis of peptide-pulsed T2 cells and HLA-A2+/Ag+ melanoma cells, was detected using in vitro expanded CTL targeting MAA peptides AAGIGILTV(MT(27-35)), IMDQVPFSV(G(209-2M)), and YMDGTMSQV(T(368-376)). In contrast, FLWGPRALV(MAGE3(271)-(279)) and VLPDVFIRCV(GnT-V(nt38-67)) induced peptide-specific recognition of T2 target cells only, whereas ITDQVPFSV(G(209-217)), KTWGQYWQV(G9(154)), MLLAVLYCL(T(1-9)), and tumor lysate could not induce specific CTLs. Specific cytolytic activity was accompanied by interferon-gamma secretion. Peptide-pulsed dendritic cells were required only for the initial stimulation of CTLs and could be substituted by PBMCs during restimulations. The median expansion rate of CTL was five to six times, regardless of whether dendritic cells or PBMCs were used after the initial stimulation. The results delineate the conditions for effective ex vivo expansion of melanoma-specific CTLs from PBMCs of healthy donors to be used as an adjunct in allogeneic cell therapy of metastatic melanoma.
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PMID:Generation of melanoma-specific cytotoxic T lymphocytes for allogeneic immunotherapy. 1280 79


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