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)

We have shown in two allogeneic bone marrow transplant recipients that Epstein-Barr virus can be eradicated by the BMT procedure or its complications, and that these patients are susceptible to infection with a new EBV strain. This conclusion was based on a combination of EBV serology and virus strain identification ("Ebnotyping," using the size variations of 5 EBV nuclear antigens). In the present study, we conducted a serological survey of EBV infection in 153 marrow graft recipients and their donors. Ten patients who were positive for IgG antibodies against EBV viral capsid antigens prior to BMT became completely seronegative at a median of 197 days post-BMT (range 106-320 days). Four of these patients, who had received seronegative marrow, remained seronegative during prolonged periods (222 to 2105 days). Six patients had received seropositive marrow. Two of them remained seronegative during their subsequent periods of follow-up (895 and 1437 days). An additional 10 patients showed a 100-fold or greater decrease in VCA IgG antibody titers. Their titers reached a nadir of 10 (the lower limit of positive) at a median of 134 days post BMT (range 83-386 days). The serological patterns of the above 20 patients were particularly frequent among patients with chronic graft-versus-host disease; 12 of 20 patients with decreasing VCA titers (60%) developed chronic GVHD versus only 22 of 73 patients with stable or increasing VCA titers (30%). These results suggest that GVHD may contribute to the elimination of residual EBV-carrying recipient cells. Establishment of EBV-carrying lymphoblastoid cell lines (LCL) was attempted in 60 donor-recipient pairs whose cryopreserved peripheral blood mononuclear cells were available. LCL were established from 18 of 51 EBV-seropositive marrow donors and 10 of 57 seropositive recipients prior to BMT. The same EBV strain was detected in 4 of the 6 cases in which LCL could be established from both the donor and the recipient prior to BMT. The persistence of the original EBV strain was demonstrated in a recipient of a T cell-depleted graft who showed only transient hematological recovery and no GVHD, and was associated with the persistence of B cells of recipient origin.
 ...
PMID:Serological and molecular studies of Epstein-Barr virus infection in allogeneic marrow graft recipients. 215 59

Fourteen patients with T-cell-derived leukemia and lymphoma underwent high-dose chemoradiotherapy and anti-T-cell monoclonal antibody-treated autologous bone marrow transplantation (ABMT). All patients were either in sensitive relapse or had adverse prognostic features, and five patients had a history of bone marrow involvement with disease. Patients received a median of 2 (1 to 3) prior chemotherapy regimens; 10 patients received local radiotherapy. After high-dose ablative therapy, greater than 500/mm3 granulocytes and greater than 20,000 untransfused platelets/mm3 were noted at a median of 23 (13 to 48) and 26 (15 to 43) days post-ABMT, respectively. Natural killer (NK) cells, T cells (predominantly T8+), and monocytes were noted within the first 1 to 2 months post-AMBT, as seen in other series. Disease-free survival was a median of 10.1 months, 5.9 months for patients with T acute lymphoblastic leukemia or lymphoblastic lymphoma and 25.6 months for patients with T non-Hodgkin's lymphoma (NHL). Toxicities were common and severe. Thirty-six percent of patients developed bacteremias early post-BMT. Late complications included a skin rash consistent with graft versus host disease; infections with Herpes zoster, hepatitis, and Pneumocystis carinii; and the development of Epstein-Barr virus associated lymphoproliferative syndrome. Our findings suggest that patients who have undergone T-depleted ABMT have a profound immunodeficiency not reflected in the phenotypic reconstitution of the T and NK cells. Characterization of the functional deficiency may facilitate the development of methods to reduce the long-term toxicity of AMBT in these patients.
 ...
PMID:T-cell-depleted autologous bone marrow transplantation therapy: analysis of immune deficiency and late complications. 219 91

In the present report we have attempted to examine immunologic reconstitution following high-dose chemoradiotherapy and anti-B-cell monoclonal antibody (MoAb)-purged autologous bone marrow transplantation (ABMT). By cell-surface phenotypic analysis, the majority of patients had normal percentage of natural killer cells (NK), monocytes, and CD8+ T cells at one month post-ABMT. In contrast, the percentage of CD4+ T cells was reduced for at least 3 years, and the CD4:CD8 ratio reflected this imbalance. B-cell reconstitution was slightly prolonged, with normal percentage and absolute numbers of CD20+ B cells evident by 3 months. Although B cells returned by 3 months, in vitro assessment of B-cell function demonstrated impairment of proliferative responses to either anti-immunoglobulins bound to beads (anti-Ig), Epstein-Barr virus (EBV), or interleukin-2 (IL-2) for approximately 1 year and low molecular B-cell growth factor (BCGF) for approximately 2 or more years. Moreover, in vivo B-cell reconstitution demonstrated a more selective defect, with normal levels of immunoglobulin IgM returning at 6 months, IgG at 12 months, and IgA after 2 years. Despite normal numbers of B cells and relative normal levels of Ig early following ABMT, our in vitro data suggest an intrinsic defect in B-cell responsiveness. Moreover, these defects are similar to those observed following nonpurged autologous and allogeneic BMT, although the interval of immune impairment appears more prolonged.
 ...
PMID:Anti-B-cell monoclonal antibody-purged autologous bone marrow transplantation for B-cell non-Hodgkin's lymphoma: phenotypic reconstitution and B-cell function. 247 24

The influence of pretransplant herpes virus antibodies in patients and donors in the subsequent development of chronic graft-versus-host disease (GVHD) was analysed in 150 consecutive HLA identical bone marrow recipients. The Cox regression bivariate analysis showed that (i) pretransplant seropositivity for cytomegalovirus (CMV) in the patients and the donors, (ii) donor seropositivity for herpes simplex virus and Epstein-Barr virus, (iii) high donor and patient age, (iv) a previous grade II-IV acute GVHD, (v) patients receiving unirradiated donor buffy coat cells post-transplant, (vi) overall CMV infection, (vii) high donor herpes virus load (positive serology for 3-4 herpes viruses versus 0-2), and (viii) high recipient herpes virus load prior to BMT were all associated with a high incidence of chronic GVHD. In Cox regression multivariate analysis, high pretransplant donor herpes virus load (p less than 0.001) and a previous grade II-IV acute GVHD (p = 0.02) were the strongest predictors of chronic GVHD. Thus, herpes virus immune cells in the donated marrow may play a role in the pathophysiology of chronic GVHD.
 ...
PMID:Pretransplant herpes virus serology and chronic graft-versus-host disease. 255 36

The specific antibody response to Epstein-Barr virus (EBV) antigens of 41 bone marrow transplant recipients with leukemia or aplastic anemia was examined retrospectively by immunofluorescence test (IF) over 1 year. We observed high titers (greater than 640) of IgG-viral capsid antigen (VCA) with emergence of IgG-early antigen (EA) and frequent absence or low levels of Epstein-Barr nuclear antigen (EBNA) antibodies. After absorption to remove rheumatoid factor (RF), five of the 41 recipients had IgM-VCA antibody to EBV, which appeared between weeks 26 and 48 after BMT and persisted for 1-4 months. No heterophil antibodies were detected in these sera, and none of the five recipients had a history of infectious mononucleosis.
 ...
PMID:Epstein-Barr virus serology in bone marrow transplantations: a one-year retrospective study with detection of EBV IgM-VCA-specific antibodies. 301 81

After T-cell depleted marrow transplantation, there is a rapid recovery of cytotoxic effector cells, with activity against targets not susceptible to killing by 'resting' natural killer cells. These targets include Epstein-Barr virus transformed B cells and leukaemic cell lines. Activated killer cell function declines by 3 months after transplantation. We find that when CD3 negative effector cells are obtained from these patients and cultured in vitro with interleukin 2 there is a further enhancement of cytotoxic activity against a range of target cells in the early post-transplant period, and a restoration of high level cytotoxic activity to effector cells obtained 3 months or more after the procedure. These results may have relevance to attempts to reduce the incidence of leukaemic relapse, and EBV + ve lymphoma outgrowth after T-cell depleted BMT.
 ...
PMID:Interleukin 2 enhances cytotoxic cell function in vitro after T-cell depleted marrow transplantation. 331 10

The infusion of donor lymphocytes after allogeneic bone marrow transplantation is a promising therapeutic tool for achieving a graft versus leukemia (GvL) effect in case of leukemic relapse (1-7), and for the treatment of other complications related to the severe immunosuppressive status of transplanted patients, such as Epstein Barr virus-induced lymphoproliferative disorders (EBV-BLPD) (8) or reactivation of CMV infection (9). Although the delay in the administration of T lymphocytes is expected to reduce the risk of severe GvHD, this risk is still present at higher doses of donor T-cells. The transfer of a suicide gene into donor lymphocytes could allow the in vivo selective elimination of cells responsible for severe GvHD. Additionally, under appropriate conditions, it may allow in vivo modulation of donor anti-tumor responses, and to separate GvL from GvHD. Finally, crucial questions concerning survival and function of donor lymphocytes could be answered by their gene marking. Previous studies documented that T lymphocytes are suitable targets for gene transfer through retroviral vectors (10, 11). This protocol has been designed to evaluate in the contest of allogeneic BMT: 1--the safety of increasing doses of donor lymphocytes transduced with a suicide retroviral vector; 2--the efficacy in terms of survival and immunologic potential of donor lymphocytes after in vitro activation, gene transduction, and immunoselection; 3--the possibility of in vivo down regulation of GvHD by the administration of ganciclovir to patients treated by tk-transduced donor lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Transfer of the HSV-tk gene into donor peripheral blood lymphocytes for in vivo modulation of donor anti-tumor immunity after allogeneic bone marrow transplantation. 754 81

Epstein-Barr-associated lymphoproliferative disorders have been described as complications of immunodeficiency states including allogeneic BMT. There is, however, only one report in the English language literature of such a disorder after autografting. We report a 56-year-old man undergoing autologous BMT for CML in whom a rapidly progressive lymphoproliferative disorder showing the histology of typical post-transplant lymphoproliferative disorder with latent EBV presence developed at approximately 30 days after BMT. Therapy with corticosteroids, acyclovir and alpha-interferon was instituted and led to prompt resolution of symptoms and signs. There was no evidence of lymphoproliferative disease at 7 months after BMT. It is concluded that EBV-associated lymphoproliferative disorders may be a complication, albeit a rare one, of intensive therapy with autologous stem cell support.
 ...
PMID:Polyclonal Epstein-Barr virus-associated lymphoproliferative disorder following autografting for chronic myeloid leukemia. 765 94

After BMT, donor T cells are activated which can display GvHD as well as GvL activities. In order to study this GvL-specific T-cell response in vitro, proliferative T-cell clones from post-BMT PBMCs were generated by stimulation with a patient's leukemic cells. One CD4+ T-cell clone (designated M-33) displayed strong proliferative activity against the patient's leukemic cells but not against the patient's EBV-LCLs. The induction of proliferation, however, appeared not to be leukemia specific. Detailed analysis of the reactivity patterns revealed that T-cell clone M-33 recognizes an as yet unknown nonpolymorphic determinant in the context of self HLA-DRw52, presented by all but one type of APC. T-cell clone M-33 proliferated upon stimulation by PB-MCs, freshly isolated B cells, monocytes, dendritic cells, leukemic B cells, and nonleukemic B-cell blasts; solely in vitro EBV-transformed B cells and in vivo EBV-infected B cells failed to induce proliferation of T-cell clone M-33. Neither surface expression of MHC or accessory molecules on the EBV cells nor suppression caused by the EBV-infected cells could explain their failure to stimulate T-cell clone M-33. We therefore hypothesize that the absence of the stimulatory capacity once the B cells are virally infected could be the result of competition for MHC class II binding of the Epstein-Barr viral peptides, thus affecting the postulated DRw52-restricted peptide for recognition by T-cell clone M-33.
 ...
PMID:Epstein-Barr virus infection abrogates the stimulatory capacity of B cells to a major histocompatibility complex class-II-restricted proliferative T-cell clone. 774 17

In allogeneic bone marrow transplantation (allo-BMT), donor lymphocytes play a central therapeutic role in both graft-versus-leukemia (GvL) and immune reconstitution. However, their use is limited by the risk of severe graft-versus-host disease (GvHD). Eight patients who relapsed or developed Epstein-Barr virus-induced lymphoma after T cell-depleted BMT were then treated with donor lymphocytes transduced with the herpes simplex virus thymidine kinase (HSV-TK) suicide gene. The transduced lymphocytes survived for up to 12 months, resulting in antitumor activity in five patients. Three patients developed GvHD, which could be effectively controlled by ganciclovir-induced elimination of the transduced cells. These data show that genetic manipulation of donor lymphocytes may increase the efficacy and safety of allo-BMT and expand its application to a larger number of patients.
 ...
PMID:HSV-TK gene transfer into donor lymphocytes for control of allogeneic graft-versus-leukemia. 920 27


1 2 3 Next >>