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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)
Relapse continues to be a problem after bone marrow transplantation (BMT) for hematologic malignancies, particularly in recipients of autologous or T-cell-depleted allogeneic grafts and in patients with advanced disease. Interferon (IFN) has shown antiproliferative activity in several malignant hematologic diseases and potentially may be of benefit when administered early after BMT when the number of residual cells is minimal. We tested in a phase I study the maximum tolerated daily dose of recombinant IFN alpha-2b in patients who had received a transplant for a disease at high risk for relapse (acute myeloid leukemia or non-Hodgkin's lymphoma beyond first remission, advanced myelodysplastic syndrome, acute lymphoblastic leukemia at any stage, chronic myeloid leukemia in accelerated or blast phase. Recombinant IFN alpha-2b was started at a dose of 0.5 x 10(6) IU/m2 and escalated by 0.5 x 10(6) IU/m2 in groups of three or four patients. The intention was to administer IFN as soon as stable engraftment after BMT was achieved (defined as an absolute neutrophil count of greater than 2.0 x 10(9)/L and platelet count greater than 100 x 10(9)/L for 5 consecutive days) and continued for 2 months. A total of 14 patients were enrolled after autologous (n = 3) or allogeneic (n = 11) BMT. Dose-limiting toxicity was myelosuppression. Significant (grade 2 to 4) neutropenia and thrombocytopenia led to discontinuation or dose reduction in five of eight patients receiving 1.5 x 10(6) or 2 x 10(6) IU/m2 IFN. Mild to moderate (grade 1 or 2) anorexia, weight loss, and fatigue occurred in the majority of patients independent of the IFN dose. De novo acute
GVHD
responsive to steroid treatment developed in 3 of 11 allograft recipients. Natural killer (NK) cell function was low before IFN treatment and was not improved with the cytokine. Conversely, interleukin-2-activated NK cells showed normal function even before starting IFN and no change was seen during IFN treatment. Clonogenic hematopoietic progenitor studies showed depression of all progenitor lines (colony-forming unit [CFU]-granulocyte, erythroid, monocyte,
megakaryocyte
, CFU granulocyte-macrophage, burst-forming unit-erythroid) by IFN at all dose levels except at 0.5 x 10(6) IU/m2. Considering this result and the incidence and severity of marrow depression seen at doses greater than 1.0 x 10(6) IU/m2, we would consider this the maximum dose safely tolerated if IFN alpha-2b is administered in this setting for a prolonged course on a daily basis.
...
PMID:Treatment with recombinant interferon (alpha-2b) early after bone marrow transplantation in patients at high risk for relapse [corrected]. 174 91
Megakaryocyte growth-promoting activity (MK-GPA) was scored on a scale of 0-3 in the serum of 23 patients up to 120 d following bone marrow transplantation (BMT) for leukaemia. Nine of 19 allografts and two of four autografts had thrombocytopenia requiring platelet transfusion more than 30 d after BMT. There was a close correlation between MK-GPA and platelet count. MK-GPA reached a maximum before day 30 after BMT but remained elevated in patients with persisting thrombocytopenia secondary to poor engraftment,
graft-versus-host disease
(
GVHD
) or relapse. Recent platelet transfusion did not suppress serum MK-GPA. Two of four patients undergoing autologous BMT for acute myeloid leukaemia (AML) showed delayed platelet recovery and persistence of MK-GPA in the serum. Seven further AML remission marrows were tested for
megakaryocyte
production before or after autologous BMT, using pooled sera with known MK-GPA activity. Megakaryocyte generation was reduced before BMT and absent in post transplant samples. This failure of MK production was not corrected by T-cell depletion or by the presence of adherent cells from normal marrow. We conclude that thrombocytopenia after BMT is associated with an appropriate increase in MK-GPA levels in response to a reduction in the
megakaryocyte
pool rather than the platelet pool, and that persisting thrombocytopenia after autologous BMT is due to decreased numbers of available
megakaryocyte
precursors.
...
PMID:Thrombocytopenia after bone marrow transplantation for leukaemia: changes in megakaryocyte growth and growth-promoting activity. 237 5
Immune thrombocytopenia occurred in 6 of 33 engrafted dogs (18%) after fetal liver hematopoietic cell transplantation. Concurrent granulocytopenia occurred in three of six dogs and anemia in one. All dogs were receiving cyclosporin to prevent graft rejection and
graft-versus-host disease
(
GVHD
). None of the dogs had signs of
GVHD
. Bone marrow obtained at the time of platelet nadir was hypercellular with
megakaryocyte
hyperplasia. All dogs exhibited anti-
megakaryocyte
antibodies detected by direct immunofluorescence of bone marrow smears. Treatment with oral prednisolone resulted in normalization of platelet counts in five of six dogs and granulocyte and erythrocyte counts in dogs exhibiting concurrent leukopenia or anemia. Two long-term survivors (greater than 2.5 years) have not developed further hematologic abnormalities since initial diagnosis and treatment.
...
PMID:Immune thrombocytopenia in dogs after fetal liver hematopoietic cell transplantation. 256 91
We have evaluated the transplantation potential of bone marrow stem cell concentrates isolated from the 40/60% interface of discontinuous Percoll gradients. This mononuclear fraction is free from platelets and depleted of granulocytes, and contains the majority of granulocyte-macrophage colony-forming cells (GM-CFC), erythroid burst-forming units (BFU-E), and granulocyte, erythroid, macrophage,
megakaryocyte
colony-forming cells (GEMM-CFC) in less than 10% of the cell number of the original buffy coat. This preparation allows further manipulation without the clumping and cell loss associated with buffy coat cell preparations. Cells isolated by this technique were evaluated for hematopoietic restoration potential in 14 patients who received allogeneic bone marrow transplants as supportive therapy after high dose cytoreduction to treat leukemias or lymphoma. The number of nucleated cells infused varied from 1.6-5.5 X 10(7)/kg, and the number of GM-CFC infused ranged from 0.4 to 3.7 X 10(5)/kg. There was an inverse relationship between the time to recovery of granulocytes and platelets and the number of GM-CFC infused when fewer than 10(5) GM-CFC/kg were transplanted. Above this dose, there was recovery within 10-15 days after transplantation. The stem cell-enriched fraction contained 30-40% of the original number of T lymphocytes, and acute
graft-versus-host disease
was observed in seven of these patients.
...
PMID:Clinical application of Percoll gradient-separated bone marrow. 290 72
This article has outlined the special problems associated with evaluation of bone marrow before and after BMT. Marrow grafting has become a major form of therapy in oncology and hematology whose potential is only beginning to be fully realized. The transplantation of healthy hematopoietic and lymphoid cells has made possible the use of otherwise superlethal doses of radiation and chemotherapy in preparing the patient for engraftment. In the case of tumors, this allows massive doses of tumorocidal therapy prior to rescue with a BMT. In the case of aplastic anemia, it allows massive immunosuppression and ablation of the residual host marrow in preparation for replacement by the healthy donor marrow. The complications of this procedure include the toxicity of chemotherapy and irradiation upon the liver, lung, and gut as well as less serious toxicity to skin and other organs. The double barrier associated with marrow transplantation consists of rejection and
GVHD
. Marrow graft failure occurs by two distinct mechanisms, graft resistance and graft rejection. The former is marked by a total failure of any evidence of engraftment and the latter by engraftment followed by disappearance of the graft.
GVHD
is the immunologic attack upon host tissues by donor lymphoid cells (predominantly mature T cells). In the acute phase, it attacks liver, skin, and gut, with the latter producing the most life-threatening syndrome. Chronic GVHD resembles scleroderma. Treatment of
GVHD
includes the use of prednisone, cyclosporin A, ATG, and monoclonal antilymphoid antibodies. Prevention includes the attempt to remove T cells from the donor marrow with monoclonal antibodies using complement-mediated cytolysis and other approaches such as conjugation of antibodies to ricin and other toxins.
GVHD
also produces severe immunosuppression in and of itself added to that produced by chemoirradiation therapy. As a result, the marrow transplant recipient is extremely susceptible to infections. During the early period, the patient is granulocytopenic and susceptible to bacterial and fungal infections, which are dealt with by antibiotics and isolation procedures. Later, viral infections become very important, particularly CMV and other herpes viruses. The relative success in dealing with bacterial and, to some extent, viral infections has brought fungal infections to the fore as major causes of death, especially in higher risk categories of patients. Hemorrhage is a frequent complication owing to delayed
megakaryocyte
engraftment and thrombocytopenia during the early period and is a serious problem in patients with
GVHD
of the gut.
...
PMID:Pathology of bone marrow in transplant recipients. 306 26
In order to study the relationship between plasma and platelet von Willebrand factor (vWF), we used an experimental model of crossed bone marrow transplantation (BMT) between SLA immunocompatible normal and homozygous von Willebrand (vWD) pigs. A normal pig received bone marrow from a vWD pig and a second pig with vWD was engrafted with marrow from a normal pig. Each recipient, after total irradiation of 10 Grays, received by a central catheter 10(10) monocellular bone marrow cells without immunosuppression. The animals were followed for 50 d and no graft rejection or
graft-versus-host disease
was observed. After aplasia occurring 3 weeks after BMT, white blood cells and platelets returned to normal. Before transplantation, in the vWD pig, vWFAg and vWF activity were not detected in plasma and in platelet and
megakaryocyte
alpha-granules. After transplantation with normal marrow, platelet vWFAg and platelet vWF activity wer normal and high molecular weight multimers and numerous tubular structures were present in alpha-granules. Before transplantation, the normal pig had normal plasma and platelet vWFAg-vWF activity, normal multimeric pattern, and the platelet and
megakaryocyte
alpha-granules displayed many tubular structures, eccentrically located in one of their poles, coinciding with immunogold staining vWFAg. After transplantation with homozygous vWD marrow, platelet and
megakaryocyte
alpha-granules lacked tubular structures. Alpha-granule immunogold staining for vWF was consistently negative, although plasma vWF was at a normal level. In conclusion, this study shows that, unlike other plasma proteins such as fibrinogen. vWF endocytosis does not occur from plasma to the platelet alpha-granules. Platelet and
megakaryocyte
vWF solely originates from
megakaryocyte
endogenous synthesis and is independent of plasma vWF.
...
PMID:Absence of incorporation of plasma von Willebrand factor into porcine platelet alpha-granules. 764 7
Autoimmune thrombocytopenia (AITP) after bone marrow transplantation (BMT) was suggested to occur by immune dysregulation mainly in association with
graft-versus-host disease
(
GVHD
). Here we present a patient who developed severe AITP after BMT. A 40-year-old woman with severe aplastic anemia received a BMT from a partially HLA-matched brother. Despite myeloid and erythroid engraftments, platelet recovery was delayed. All bone marrow cells were 46,XY and were derived from the donor. Grade I acute
GVHD
involving skin developed from day 34 posttransplantation, but promptly responded to prednisolone in addition to a prophylactic dose of tacrolimus. With the tapering of prednisolone, thrombocytopenia progressed without substantial changes in the white blood cell count, hemoglobin concentration, or reticulocyte count. On day 188, the patient developed chronic
GVHD
involving skin and liver, which promptly responded to the readministration of prednisolone and increased tacrolimus. However, the patient's platelet count decreased to 9 x 10(9) cells/L on day 222. The platelet-associated immunoglobulin G (PAIgG) values were elevated. Bone marrow examination showed hypercellularity with plentiful megakaryocytes. The number of colony-forming units-
megakaryocyte
was within the normal range. The elevated PAIgG values and a correlation between thrombocytopenia and the intensity of the immunosuppressive agents strongly suggested a causative role of the autoimmune mechanisms for thrombocytopenia in this patient.
...
PMID:Severe autoimmune thrombocytopenia after allogeneic bone marrow transplantation for aplastic anemia. 1159 27
The objective of this study was to quantify subpopulations of CD34+ cells such as CD41+ and CD42+ cells that might represent
megakaryocyte
(MK) precursors in peripheral blood stem cell (PBSC) collections of normal, recombinant human granulocyte-colony stimulating factor (rhG-CSF) primed donors and to determine whether there is a statistical association between the dose infused megakaryocytic precursors and the time course of the platelet recovery following an allogeneic PBSC transplantation. Twenty-six patients with various hematologic malignancies transplanted from their HLA identical siblings between July 1997 and December 1999 were used. All patients except one with severe aplastic anemia who had cyclophosphamide (CY) alone received busulfan-CY as preparative regimen and cyclosporine-methotrexate for
GVHD
prophylaxis. Normal healthy donors were given rhG-CSF 10 microg/kg/day subcutaneously twice daily and PBSCs were collected on days 5 and 6. The median number of infused CD34+, CD41+ and CD42+ cells were 6.61 x 10(6)/kg (range 1.47-21.41), 54.85 x 10(4)/kg (5.38-204.19), and 49.86 x 10(4)/kg (6.82-430.10), respectively. Median days of ANC 0.5 x 10(9)/L and platelet 20 x 10(9)/L were 11.5 (range 9-15) and 13 (8-33), respectively. In this study, the number of CD41+ and CD42+ cells infused much better correlated than the number of CD34+ cells infused with the time to platelet recovery of 20 x 10(9)/L in 26 patients receiving an allogeneic match sibling PBSC transplantation (r = -0.727 and P < 0.001 for CD41+ cells, r = -0.806 and P < 0.001 for CD42+ cells, r = -0.336 and P > 0.05 for CD34+ cells). There was an inverse correlation between the number of infused CD41+ and CD42+ cells and duration of platelet engraftment. Therefore, as the number of CD41+ and CD42+ cells increased, duration of platelet engraftment (time to reach platelet count of > or = 20 x 10(9)/L) shortened significantly. Based on this data we may conclude that flow cytometric measurement of CD41+ and CD42+ progenitor cells may provide an accurate indication of platelet reconstitutive capacity of the allogeneic PBSC transplant.
...
PMID:CD41+ and CD42+ hematopoietic progenitor cells may predict platelet engraftment after allogeneic peripheral blood stem cell transplantation. 1174 31
Umbilical cord blood (CB) from unrelated donors is increasingly used to restore hematopoiesis after myeloablative therapy. CB transplants are associated with higher rates of delayed and failed engraftment than are bone marrow transplants, particularly for adult patients. We studied the ex vivo expansion of CB in an attempt to improve time to engraftment and reduce the graft failure rate in the recipients. In this feasibility study, 37 patients (25 adults, 12 children) with hematologic malignancies (n = 34) or breast cancer (n = 3) received high-dose therapy followed by unrelated allogeneic CB transplantation. A fraction of each patient's CB allograft was CD34-selected and cultured ex vivo for 10 days prior to transplantation in defined media with stem cell factor, granulocyte colony-stimulating factor, and
megakaryocyte
growth and differentiation factor. The remainder of the CB graft was infused without further manipulation. Two sequential cohorts of patients were accrued to the study. The first cohort had 40% and the second cohort had 60% of their CB graft expanded. Patients received a median of 0.99 x 10(7) total nucleated cells (expanded plus unexpanded) per kilogram. The median time to engraftment of neutrophils was 28 days (range, 15-49 days) and of platelets was 106 days (range, 38-345 days). All evaluable patients who were followed for 28 days or longer achieved engraftment of neutrophils. Grade III/IV acute
GVHD
was documented in 40% and extensive chronic
GVHD
in 63% of patients. At a median follow-up of 30 months, 13 (35%) of 37 of patients survived. This study demonstrates that the CD34 selection and ex vivo expansion of CB prior to transplantation of CB is feasible. Additional accrual will be required to assess the clinical efficacy of expanded CB progenitors.
...
PMID:Transplantation of ex vivo expanded cord blood. 1217 83
The BMT program at Princess Margaret Hospital performed 105 transplants using cryopreserved peripheral blood stem cells (PBSC) from related allogeneic donors. The outcomes were compared with those of a historic control of 106 patients transplanted with freshly procured PBSC. The infusions were tolerated with limited toxicity related to nausea/vomiting or bradycardia, correlated with the total amount of DMSO infused. The average viability of the total nucleated cell (TNC) population after thawing was 71%. The survival of clonogenic progenitors amounted to 75% for colony-forming unit-granulocyte-macrophage (CFU-GM), 69% for burst-forming units erythroid (BFU-E), and 78% for colony-forming units granulocyte-erythrocyte-monocyte-
megakaryocyte
(CFU-GEMM). In contrast, colony-forming units
megakaryocyte
(CFU-MEG) was significantly more cryosensitive with recovery rates of 39%. The number of viable CD34(+) cells transplanted was correlated with the number of transplanted viable CFU-GM (P < .001), BFU-E (P < .001), CFU-MEG (P < .001), and CFU-GEMM (P = .049), but not with the TNC dose. The number of transplanted CD34(+) cells was correlated with engraftment of neutrophils (P = .012) and platelets (P = .013). The outcomes of cryopreseved or fresh PBSC transplants (PBSCT) with respect to engraftment of neutrophils (P = .178) and platelets (P = .785), lymphocyte recovery (P = .926), acute (P = .113), and chronic
graft-versus-host disease
(P = .673), recurrence (P = .295), nonrelapse mortality (P = .340), and overall survival (P = .668) were not significantly different. It is therefore reasonable to consider the option of cryopreserved allografts.
...
PMID:Similar outcomes of cryopreserved allogeneic peripheral stem cell transplants (PBSCT) compared to fresh allografts. 1788 61
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