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)

A combination of density flotation centrifugation and counterflow centrifugation (elutriation) allows the elimination of 98% of the T-lymphocytes, present in a marrow aspirate. This reduces substantially the occurrence of graft versus host disease (GvHD) after transplantation without loss of the repopulation capacity. A limitation of the traditional Beckman elutriator rotor is the relatively small size of the elutriation chamber, which makes five to six runs, of one hour each, necessary to process the whole bone marrow graft. We developed a new elutriator rotor, containing four disposable elutriator chamber (Dijkstra BV, Amsterdam, The Netherlands), which allows to complete the lymphocyte elimination from the bone marrow graft within 2 hours. Ninety-nine consecutive patients were transplanted with elutriated MLC-negative bone marrow grafts from histocompatible siblings. Indications for transplantation were: AML (n = 32), ALL (n = 34) and CML (n = 33). The grafts contained after counterflow centrifugation a mean of 12.1 (+/- 2.4)% of the nucleated cells, 1.9 (+/- 1.4)% of the T-lymphocytes, and 93.5 (+/- 59.4)% of the CFU-GM, originally present in the collected bone marrow. Immunoprophylaxis post grafting was given to 97 BMT recipients. Primary graft failure occurred in 5 of 95 evaluable patients (5%). The probability of acute GvHD greater than grade 1 at day 100 after BMT was 16%. The projected 3-year estimate of extensive chronic GvHD was 13%. The low incidence of GvHD was associated with a relatively low transplant related mortality in patients above the age of 40 years.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prevention of graft-versus-host disease by lymphocyte depletion of the bone marrow graft with use of counterflow centrifugation. 186 51

Bone marrow transplantation has proven its value as a therapeutic approach to a variety of human diseases, primarily the hematopoietic malignancies. The major clinical problems preventing successful outcome of marrow transplant have been defined and therapeutic approaches to preventing or treating these complications have led to increased long-term disease survival. Passively administered antibody given as intravenous immunoglobulin has been studied as a therapeutic modality following bone marrow transplantation. Studies have demonstrated the efficacy of immunoglobulin in reducing bacterial infections in the posttransplant period; reducing severe CMV infections in allogeneic marrow transplant recipients who are seronegative for the virus and susceptible to primary infection; reducing mortality from CMV pneumonia in combination with ganciclovir; and reducing acute graft-versus-host disease following allogeneic BMT. In many cases alternate therapeutic strategies offer comparable or greater efficacy (eg, selective CMV-negative blood products for CMV seronegative allogeneic BMT recipients receiving bone marrow from a seronegative donor). However, it is clear that intravenous immunoglobulin has a place in the therapeutic armamentarium of bone marrow transplantation. Future controlled clinical trials are necessary to establish its exact role and to define which preparations and dose schedules provide the greatest therapeutic benefits.
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PMID:The role of immunoglobulin in bone marrow transplantation. 187 29

This report investigates the effects of cyclosporine on the reconstitution of T lymphocytes after syngeneic bone marrow transplantation and its role in the development of a novel T cell-mediated autoimmune disease, syngeneic graft versus host disease. We analyzed the effect of CsA treatment on T lymphocyte differentiation during reconstitution after bone marrow transplantation and correlated the maturation of CD4+ and CD8+ T cell subsets with the onset of syngeneic GVHD. Administration of CsA following syngeneic bone marrow transplantation leads to a developmental arrest of mature CD4+ and CD8+ T lymphocytes in the thymus and a marked reduction in cells expressing the alpha beta T cell receptor. The reduction of CD4+ and CD8+ T cell subsets is also reflected in the peripheral lymphoid compartment with an altered CD4/CD8 ratio. Functional assessment of the cells revealed that CD8+ cells respond normally to mitogenic signalling whereas CD4+ cells exhibit marginal proliferative responses. Both subsets of T lymphocytes respond to syngeneic B lymphoblasts, comparable to the response of T lymphocytes from non-CsA-treated syngeneic BMT recipients, suggesting that autoreactive cells are produced despite CsA treatment. Following discontinuation of CsA, T cell differentiation in the thymus is rapidly restored to normal. However, concurrent with the onset of syngeneic GVHD, a compensatory insurgence of CD4+ T helper cells is observed.
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PMID:Effect of cyclosporine on T lymphocyte development. Relationship to syngeneic graft-versus-host disease. 189 96

After bone marrow transplantation many T-lymphocyte functions, including the production of cytokines (CK), such as interleukin 2, are severely depressed for months. The monocyte-derived cytokines tumor necrosis factor alpha and interleukin 6 are molecules central to immune functions. Moreover, they may be involved in graft-versus-host disease and in graft-versus-leukemia reaction. Hence, we have studied the reappearance of these CKs after BMT by analyzing whole blood cultures stimulated in vitro with lipopolysaccharide for 6 hr, followed by testing for the secretion of TNF in the WEHI 164/actinomycin D cytotoxicity bioassay and for IL-6 in the 7 TD 1 proliferation assay. We performed sequential studies in 6 children who were transplanted for aplastic anemia or leukemia with allogeneic bone marrow. We found that the production of both CKs can be induced as early as 10-14 days post BMT at the very beginning of engraftment, indicating that the regenerating monocyte system is recovering rapidly after BMT. Depletion and neutralization experiments confirmed that monocytes are the cellular source of the LPS-induced CK secretion after BMT. Control levels were reached 3 to 4 weeks post BMT. When analyzing the endotoxin-induced CK production in a larger panel of BMT patients after complete reconstitution, we could not detect any impact of acute or chronic GvHD, or of allogeneic or autologous BMT, nor did treatment with cyclosporine A (CsA) show any suppressive effect. Thus, our data show that the CK production of the monocyte/macrophage lineage is quite resistant to factors that do influence other cell lineages of the immune system during BMT. The coincident appearance of monocyte-derived cytokines and of GvHD suggests a role for these cytokines in GvHD in man.
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PMID:Recovery of monocytes after bone marrow transplantation--rapid reappearance of tumor necrosis factor alpha and interleukin 6 production. 192 48

Three groups of patients with leukaemia and myelodysplasia were assessed with regard to the blood product support they required during their period of bone marrow hypoplasia following treatment. One group received myelo-ablative remission-induction chemotherapy followed by appropriate consolidation therapy (two courses in patients with acute myeloid leukaemia and one or two intensification courses in patients with acute lymphoblastic leukaemia); whilst the other two had 'conditioning' with chemotherapy and radiotherapy prior to autologous bone marrow transplantation (auto-BMT) or T cell depleted allogeneic bone marrow transplantation (allo-BMT). There was no statistically significant difference in blood product requirements between the three groups. However, platelet requirements during remission-induction chemotherapy alone were significantly less than for allo-BMT or auto-BMT. Platelet requirements for patients undergoing auto-BMT were also significantly higher than for patients receiving consolidation chemotherapy; and were required for a longer period than for patients receiving allogeneic-BMT. There was no difference in blood product support between ABO matched and mismatched transplants within the allogeneic group, but the presence of graft versus host disease and/or cytomegalovirus infection did significantly increase the requirements for blood product support.
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PMID:Blood product support in patients undergoing chemotherapy and autologous or allogeneic bone marrow transplantation for haematological malignancies. 193 21

Manifestation of graft-versus-leukemia (GVL) effect in MHC-compatible and -incompatible, allogeneic bone marrow transplantation and the roles of T cell subsets contaminated in the donor bone marrow were studied using radiation-induced leukemia-bearing C3H mice maintained under specific-pathogen-free (SPF) condition. The results indicated that BMT from MHC-incompatible allogeneic (B10) donor significantly improved the survival of the treated mice as compared with that from syngeneic (C3H) donor. When donor (B10) bone marrow cells were treated with either anti-Thy 1.2 or anti-Lyt 2.2 antibody plus complement prior to BMT, a beneficial GVL effect was completely abolished. On the other hand, BMT from MHC-compatible allogeneic donors (B10.BR, CBA, AKR) failed to show an improvement in survival. However, intentional enhancement of GVH reaction by preimmunization of B10.BR donor mice with a relatively small number (10(4) approximately 10(5] of C3H spleen cells or by an addition of B10.BR lymph node cells to the donor bone marrow resulted in a significant improvement in survival. The depletion of all T cells completely abrogated the GVL effect, while the depletion of either Lyt 2+ or L3T4+ T cells from donor (B10.BR) bone marrow resulted in only partial, if any, abrogation of GVL effect. The results indicate that GVL effect observed in leukemic mice treated with allogeneic BMT from MHC-compatible (B10.BR) and -incompatible (B10) donors was totally dependent on T cells contaminated in the donor bone marrow, and suggest that the roles of T cell subsets in the induction of GVL effect were different between MHC-compatible (B10.BR) and -incompatible (B10), allogeneic BMT.
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PMID:Graft-versus-leukemia effect in MHC-compatible and -incompatible allogeneic bone marrow transplantation of radiation-induced, leukemia-bearing mice. 194 75

4 patients (3 female, 1 male) bone marrow transplanted for severe aplastic anemia (3 allogeneic, 1 syngeneic) became pregnant or parented children 19, 37, 81, and 34, 52 months, respectively, after BMT. Conditioning regimen consisted of 200 mg/kg Cyclophosphamide. Donor buffy coat cells were used for rejection prophylaxis, and methotrexate was used as GVHD prophylaxis. 1 female patient developed a mild chronic graft versus host disease with vaginal sclerosis which made a cesarean section necessary. 3 out of 5 pregnancies were uneventful. 1 patient had mumps in the 14th week, another patient had a late abortion in the 25th week of unknown cause. A high incidence of offspring complications was noticed including 1) persistence of fetal circulation syndrome, 2) erythroblastosis fetalis, and 3) prolonged newborn-icterus. These observations confirm previous reports on resumed fertility after BMT for SAA. A relation between the unexpected high incidence of pre-, peri-, and postpartal complications and the BMT procedure can neither be proved nor excluded.
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PMID:[Pregnancy and fetal complications after bone marrow transplantation]. 194 50

In conclusion, lessons from the animal model of lymphoid leukaemia suggest that in the setting of allogeneic BMT, under certain conditions GVL effects may be separable from GVHD; more specifically, GVL effects may be induced despite development of tolerance of donor cells against allogeneic host alloantigens. The latter phenomenon suggests that either curative GVL effects may be inducible despite subclinical GVHD or alternatively that effector cells of GVL may recognize different tumour-associated targets different from cell surface determinants of 'normal' alloantigens. Alternatively, effector cells of GVL may be distinguished from effector cells of GVHD. It is tempting to suggest that NK and IL2-aspirated NK cells may play a major role as effector cells of GVL in an MHC non-restricted fashion, different from classical CD8+ cytotoxic cells that certainly play a major role in GVHD and GVL. Once proven, the latter hypothesis may help develop new and safer therapeutic approaches since NK cells and products of the NK cell family are unlikely to play a major role, if any, in GVHD. The feasibility of induction of GVL-like effects by MHC non-restricted effector cells, such as that observed by CMI, most likely through cytokine-activated NK cells, seems promising because such effector mechanisms may be utilized clinically through either adoptive transfer of in vitro-activated lymphocytes or activation of lymphocytes in vivo by administration of cytokines such as IL2 and alpha IFN. Similarly, induction of CCI following ABMT may permit establishment of GVL-like effects with no major risk of GVHD. Our animal models suggest that both approaches may be beneficial and perhaps even combined. From a practical standpoint, activation of antitumour effector cells in vivo is much more feasible, in comparison with the cumbersome and expensive technologies for large-scale in vitro manipulation of IL2-activated 'LAK' cells or tumour-infiltrating lymphocytes ('TIL') at dose ranges required for obtaining clinically meaningful responses. No less important is the fact that more potent immunotherapy may be inducible by cytokine combinations (such as IL2 and alpha IFN). We are currently investigating additional cytokine combinations in order to attempt to optimize antitumour effects inducible by allogeneic and syngeneic lymphocytes since it appears logical that amplifying in vivo antitumour responses by multiple cytokine combinations may yield better antitumour effects.
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PMID:Control of relapse due to minimal residual disease (MRD) by cell-mediated cytokine-activated immunotherapy in conjunction with bone marrow transplantation. 195 88

In a study carried out for patients receiving intrafamilial HLA-A,B,DR identical, MLC negative bone marrow transplants, RFLP profiles of HLA-class II for 27 donor recipient pairs were analyzed. Twenty-four pairs were found HLA-class II identical while three pairs were HLA-DP incompatible. The patients of these three pairs did not reveal any acute GVHD greater than or equal to grade II. The seven cases of acute GVHD greater than or equal to grade II found in our panel were HLA-DR, DQ, and DP compatible. Thus, in practical terms pretransplantation HLA-DP typing does not seem necessary for intrafamilial HLA-identical, MLC negative BMT. On the other hand, this work confirmed that it is possible to type for HLA-DP using molecular biological techniques, and this in itself may have some important implications for unrelated BMT.
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PMID:HLA-DP genotyping in HLA-A,B, and DR identical intrafamilial bone marrow transplantation. 196 10

Sixteen recipient-donor pairs who underwent unrelated BMT were analyzed for their HLA-class II identity by DNA-RFLP, in order to evaluate the importance of the genotypic HLA-DR, DQ, DP identity in the clinical outcome of unrelated bone marrow transplantation. From our study, a clear correlation between the HLA-DR, DQ, and DP genetic identity and acute GVHD (aGVHD) is not obvious since the number of studied cases is still limited. Nevertheless, it seems that the genetic identity influence the clinical outcome and patient survival. Six patients out of the ten who experienced severe aGVHD (greater than grade II) differed from their respective donors by HLA-DP mismatch in the GVH direction. Two patients rejected their grafts, and both presented HLA-DP incompatibilities in both GVH and HVG directions. Hence, HLA-DP may function as a transplantation antigen like the other HLA-class II molecules (DR, DQ) in unrelated BMT. Accordingly, we propose considering it in the pretransplantation histocompatibility testing. Nevertheless, further studies with larger numbers of cases should be done in order to confirm the role of HLA-DP. No correlation was observed between the mixed lymphocyte reaction (MLR) reactivity and the incidence of aGVHD. Accordingly, MLR response seems to be an incomplete indicator of GVHD, and a functional test is still to be found.
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PMID:HLA-DR, DQ, and/or DP genotypic mismatches between recipient-donor pairs in unrelated bone marrow transplantation and transplant clinical outcome. 197 52


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