Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.1.1.69 (BMT)
 2,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The transfer of cytotoxic effector cells reduces the risk of relapse after allogeneic BMT. Two murine leukemia cell lines, A20 (B lymphocytic) and WEHI-3 (myelomonocytic), were used to investigate antileukemic effector mechanisms operating independently from graft-versus-host disease (GVHD). Different results were obtained with the two leukemia models. After injection of A20 cells, the majority of Balb/c recipients treated with syngeneic BMT died due to leukemia relapse (89%). The transplantation of MHC-matched DBA marrow resulted in chronic GvHD but did not reduce the risk of relapse (86%). Grafting of MHC-mismatched (but GvH-nonreactive) marrow cells from (C57xBalb)F1 hybrids, however, led to a significantly lower relapse rate (47%, p < 0.05). In vitro testing revealed that F1 cells but not Balb/c or DBA cells exert NK cell activity against A20. The elimination of NK 1.1-positive cells from the graft reduced the antileukemic activity of (C57xBalb)F1 marrow against A20 in vivo. After injection of WEHI-3 leukemia cells, syngeneic BMT cured most of the recipients (62%) and transplantation of (C57xBalb)F1 marrow provided no additional benefit. In contrast to unmanipulated Balb/c and (C57xBalb)F1 cells, which showed no NK activity against WEHI-3 in vitro, IL-2 treated effector cells were highly cytotoxic. Transfer of IL-2 preincubated grafts significantly decreased the relapse rate of WEHI-3 (19 vs. 38%) after syngeneic and allogeneic BMT. Our data indicate that GvL activity can be separated from GvHD. In our murine model, GvL activity appears to depend more on the donors NK/LAK cell activity than on the presence or absence of GvHD.
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PMID:Natural killer cells as effector cells of graft-versus-leukemia activity in a murine transplantation model. 812 60

Cytokine gene expression in peripheral blood mononuclear cells during the development of graft-versus-host disease (GVHD) in patients who underwent allogeneic bone marrow transplantation (allo BMT) was analysed using a semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR). The expression of interleukin (IL)-1 beta, IL-6, and tumour necrosis factor (TNF)-alpha mRNA was increased during the development of GVHD and the degree of this increment depended on the severity of the disease. IL-2 expression was not detected at all and interferon-gamma expression was not much changed during GVHD. In patients with hepatic veno-occlusive disease (VOD), another transplantation-related complication, the expression of IL-1 beta and TNF-alpha mRNA was increased but IL-6 mRNA expression showed little increase. These findings suggest that IL-1 beta, IL-6 and TNF-alpha produced by peripheral blood mononuclear cells play an important role in the development of GVHD. Furthermore, liver dysfunction due to GVHD or VOD may be distinguishable by this type of cytokine analysis. Analysis of cytokine mRNA expression in peripheral blood mononuclear cells after allogeneic bone marrow transplantation may provide important information concerning the immune response and the cytokine network system in marrow transplant patients.
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PMID:Cytokine gene expression in peripheral blood mononuclear cells during graft-versus-host disease after allogeneic bone marrow transplantation. 813 79

IL-2 has been used after autologous BMT (ABMT) with the aim of inducing graft versus leukemia (GVL) effect. Our studies in mice have shown that IL-2 therapy induces GVL effect when employed after BMT with bone marrow (BM) that has been activated with IL-2 in vitro (ABM). The present study was carried out to define the time of optimal GVL effect after BMT so that the immunomodulatory approaches could be concentrated at the time of maximum GVL effect. Our data show that GVL effect was induced if IL-2 was instituted immediately after BMT with ABM in mice with acute myeloid leukemia; institution of IL-2 1 week after BMT with ABM did not induce GVL effect. IL-2 therapy instituted immediately or 1 week after BMT with fresh bone marrow (FBM) did not induce any GVL effect. A significant increase in the NK activity was noticed whether IL-2 was instituted immediately or 1 week after BMT, either with FBM or with ABM. To evaluate the ability of IL-2 in the eradication of residual disease from the autograft and the host, BM with variable infiltration with leukemia was activated with IL-2 and used for BMT in leukemic mice. The GVL effect of BM with minimal leukemic infiltration (absence of morphologically demonstrable disease) was comparable to the GVL effect of normal BM. These findings suggest that: (a) maximum GVL effect after BMT with ABM is concentrated in the early post-transplant period possibly because of minimal residual disease during this time; (b) an increase in the NK activity induced by IL-2 therapy may not predict for an improved GVL effect; and (c) for optimum GVL effect, BM with minimal leukemic infiltration should be activated with IL-2 before BMT.
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PMID:Graft versus leukemia effect after transplantation with interleukin-2-activated bone marrow. Correlation with eradication of residual disease. 833 64

Despite intensive conditioning and marrow purging, leukemia relapse frequently follows autologous BMT for acute lymphoblastic leukemia. To generate antileukemic immunologic activity, we performed a phase I study using recombinant human interleukin 2 given immediately posttransplantation. This early period was chosen because of low disease burden; therefore induced in vivo effector:target cell ratios might be most favorable. IL-2 was given by continuous infusion (96 hr/week x 3 weeks) beginning day +1. Fourteen patients with high-risk ALL were treated at 0.5, 1.0, and 2.0 x 10(6) U/m2/day IL-2. The clinical toxicity, hemopoietic recovery, and immune activation in the IL-2-treated patients was compared with that in a group of autologous BMT patients receiving no IL-2. The patients receiving IL-2 had a trend toward earlier neutrophil, platelet, and RBC recovery plus earlier hospital discharge versus non-IL-2 controls. However, IL-2 plus the inherent toxicity of transplantation often produced hepatic, pulmonary, and renal toxicity. Assessment of immune activation induced by in vivo IL-2 (following 3 weeks of IL-2) showed proliferation of CD8+ T cells having in vitro cytotoxicity against the Nalm-6 ALL cell line in most patients. Little enhancement of natural killer activity by immunophenotype or cytotoxicity against K562 cells was observed. IL-2 given immediately post-BMT induces infrequent but significant toxicity at lower doses than in the non-BMT setting. This toxicity may result from pre-BMT conditioning in conjunction with T cell activation. The immunotherapeutic potential, dose, and schedule of IL-2 following BMT require further study along with measures to reduce its toxicity.
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PMID:Interleukin 2 immediately after autologous bone marrow transplantation for acute lymphoblastic leukemia--a phase I study. 842 66

In this review we have considered the role of ABMT for the acute leukemias. It is apparent from data around the world that ABMT is a curative therapy for patients with both AML and ALL after primary treatment failure. Other than allogeneic BMT, ABMT may be the only curative therapy following relapse, especially in AML. The role of ABMT in first CR is less well defined. There are few data to support the widespread use of ABMT in first CR for ALL. Moreover, the improved survival of adults with ALL with current intense multiagent regimens will probably obviate the need to continue clinical trials of ABMT for ALL in first CR. For patients with AML in first CR, however, it seems that ABMT may well lead to improved rates of DFS compared with chemotherapy alone. Almost every published report describes better DFS for patients who underwent ABMT compared with historical or contemporary controls who were treated with chemotherapy. One note of caution is that as chemotherapy evolves, the increment in survival currently observed from ABMT may diminish, thus rendering ABMT less obviously necessary. On the other hand, from an economic standpoint, ABMT could prove to be cost-effective, because a short, intense treatment that is effective may prove to be less costly than the current extended period of chemotherapy. Because ABMT is becoming safer, it would seem reasonable to continue its use in patients with AML at high risk for relapse (secondary AML, adverse cytogenetics, and so on) while awaiting the outcome of the randomized clinical trials currently underway that are seeking to define the role of ABMT for the general population of patients with AML after initial remission is achieved. Meanwhile, further definition of the relative value of the various purging regimens, preparative regimens, and adjunctive therapy (i.e., IL-2, mAb) warrants study.
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PMID:Autologous bone marrow transplantation for adult acute leukemia. 844 59

UVB irradiation (700 J/m2) of bone marrow cells (UVB-BMC) before transplantation into lethally gamma-irradiated (10.5 Gy) allogeneic rats prevents graft-versus-host disease (GVHD) and induces a stable complete lymphohematopoietic chimerism. To better understand the underlying mechanism of the development of stable chimerism and induction of tolerance to donor organs in this model, we examined if the addition of T cells or dendritic cells (DC), as antigen presenting cells (APC), would restore the immunogenicity of UVB-BMC in in vitro mixed lymphocyte reaction (MLR) and induce in vivo bone marrow (BM) graft rejection. Whereas gamma-irradiated, unfractionated BMC induce allogeneic T cells to proliferate, UVB irradiation of BMC abolishes the stimulatory capacity of such cells in a primary MLR. Addition of purified T cells, CD4+ T cells, CD8+ T cells or B cells, respectively, failed to restore the capacity of UVB-BMC to stimulate allogeneic T-cell proliferation. In contrast, the addition of only a small number of splenic accessory cells or purified DC, which by themselves were relatively ineffective in stimulating T-cell proliferation, restored the accessory function and the allostimulatory capacity of UVB-BMC. To define the molecular defect induced by UVB irradiation, cytokines were added as costimulatory factors to primary MLRs and the results showed that the addition of interleukin (IL)-2 or IL-6 but not IL-1 or interferon gamma (IFN-gamma) restored the stimulatory capacity of UVB BMC. This finding suggests that UVB may alter the production, and/or utilization of IL-2 and IL-6 either at the membrane or cytoplasmic level. Parallel in vivo studies showed that addition of DC to UVB BM inoculum resulted in failure of BM engraftment, whereas addition of T cells led to development of fatal GVHD, thus suggesting that UVB modulation of accessory cells reduces graft immunogenicity and prevents BMT rejection, while modulation of T cells prevents GVHD. Our data provide evidence that UVB modulation of APC and mature T cells contained within BMC is potentially useful in preventing GVHD without endangering successful engraftment and may serve as a model for induction of adult chimerism and tolerance without the development of GVHD.
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PMID:Prevention of graft-versus-host disease and bone marrow rejection: kinetics of induction of tolerance by UVB modulation of accessory cells and T cells in the bone marrow inoculum. 845 11

Myeloablative chemo (+/- radio) therapy and rescue with ABMT has been used as final consolidation therapy in 18 patients with AML in first remission. In seven (6 autologous, 1 syngeneic) marrow reinfusion was followed by iv IL-2. One patient, who commenced IL-2 4 days after BMT, died from pulmonary oedema due to the capillary leak syndrome. Thereafter, treatment with IL-2 was delayed until the platelet count reached 30 x 10(9)/l. All patients developed reversible hypotension (treated with infusion of colloid), but treatment was otherwise well tolerated. With 21-58 months (median 32 months) from the time of ABMT there has been one relapse (actuarial risk 17%, 95% confidence intervals (CI) 3-31%). The disease-free survival is 71% (95% CI 38-100%). Eleven patients with comparable remission induction and consolidation therapy, and an identical interval between diagnosis and ABMT (5-11 months, median 6 months) received an autograft without immunotherapy. With 24-45 months (median 29 months) follow-up the actuarial disease-free survival is 36% (95% CI 8-64%), the actuarial relapse risk is 54% (95% CI 18-90%). We conclude that immunotherapy given after ABMT to patients with AML in first remission when the platelet count exceeds 30 x 10(9)/l is safe and may induce an immunological environment which results in the elimination of residual leukaemia.
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PMID:Immunotherapy with interleukin 2 after ABMT in AML. 850 74

Despite intensification of treatment with high-dose chemotherapy (HDC) and autologous bone marrow transplantation (AMBT), the prognosis of poorly responding metastatic neuroblastoma remains bad. Recombinant IL-2 (rIL-2) was used after ABMT to enhance the immune response against the tumor and thereby to improve survival of these patients. In this study, five courses of rIL-2 were administered as a continuous intravenous infusion every 2 weeks, the first course lasting 5 days, and the other four 2 days. rIL-2 treatment was to begin within 120 days of BMT. This study demonstrates the feasibility of rIL-2 soon after HDC and ABMT. The maximum tolerated dose (MTD) was 12 x 10(6) U/m2/day. Clinical toxicity was similar to that observed in adults, moderately increased by the proximity of ABMT; in a previous study we demonstrated that the MTD in non-grafted children was 18 x 10(6) U/M2/day. Nevertheless, half of the patients were not able to receive rIL-2 therapy after ABMT, and only 6/12 received 100% of the planned dose, mainly because of thrombocytopenia. If peripheral stem cell transplantation is demonstrated to enhance platelet recovery, more patients could be treated with rIL-2 with the present schedule. Earlier administration of low-dose rIL-2 after BMT associated with ex vivo rIL-2 treatment of the graft could be a more valid way of using rIL-2 to improve survival.
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PMID:Phase I-II study of interleukin-2 after high-dose chemotherapy and autologous bone marrow transplantation in poorly responding neuroblastoma. 852 66

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

The toxicity and antitumor efficacy of simian IL-15 was compared with human IL-2 in the context of syngeneic BMT. Groups of mice receiving or not receiving anti-CD3 activated splenocytes, termed "T-activated killer" (T-AK) cells, were treated between days 7 and 12 with escalating doses of IL-2 or IL-15 given twice daily. Recipients of IL-2+T-AK or IL-15+T-AK had significantly higher survival rates than saline+T-AK. Tissues from IL-2+T-AK, but not IL-15+Y-AK, treated mice revealed the presence of perivascular infiltrates in the lung and liver consisting of CD8+ T cells and Mac-1+ cells. Our findings demonstrate that IL-15 can be used effectively to stimulate antitumor responses post-BMT and may be associated with less toxicity than IL-2.
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PMID:IL-15 administration following syngeneic bone marrow transplantation prolongs survival of lymphoma bearing mice. 882 94


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