Gene/Protein Disease Symptom Drug Enzyme Compound
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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)

In the present report, cytotoxic T lymphocyte (CTL) clones are described that display dual specificity for one of two common human leukocyte antigens (HLA B14 or B35) as alloantigens, and an immunodominant epitope (FLRGRAYGL) from Epstein-Barr virus (EBV) that binds to HLA B8. These T cell clonotypes were isolated from several unrelated HLA B8+, EBV-exposed individuals, and each distinct cross-reactivity pattern was associated with a common, public T cell receptor (TCR). In some individuals, CTL cross-reactive with these alloantigens completely dominated the memory response to this EBV epitope. Moreover, these memory T cells to EBV could be reactivated as a significant component of the repertoire of CTL responding to allogeneic stimulator cells expressing either HLA B14 or B35. These data illustrate how a history of infection with an immunogenic virus such as EBV can augment responsiveness to particular alloantigens; such influences may underlie the observed clinical association between herpesvirus infection and both allograft rejection and graft-versus-host disease. We have also explored the molecular basis for T cell cross-reactivity with alloantigens using the HLA B35 allo-reactive CTL clonotype. To elucidate the structural features of peptides that may be cross-recognized by these T cells, mono-substituted analogs of the viral epitope were screened for recognition, revealing broad specificity for major histocompatibility complex (MHC)-bound peptide. Based on the particular amino acid changes tolerated by the CTL at each peptide position, the human protein sequence database was searched for possible sequences that were recognized in association with HLA B35. Four peptides were identified (MPEATVYGL, IPIAPVYGM, KPSPPYFGL, and KPIVVLHGY) that were powerful activating ligands for the CTL when presented on HLA B35 but not B8. Thus, equivalent epitopes, capable of fully activating a single TCR, were formed by peptides with minimal obvious sequence homology bound to either HLA B8 or B35. These data indicate that degenerate peptide recognition by TCR may play an important role in the vigorous response of self-MHC-restricted T cells to alloantigens.
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PMID:Cross-reactive memory T cells for Epstein-Barr virus augment the alloresponse to common human leukocyte antigens: degenerate recognition of major histocompatibility complex-bound peptide by T cells and its role in alloreactivity. 924 84

The use of an HLA-compatible unrelated donor is an option for patients who require an allogeneic transplant but lack a family member match. Grafts from unrelated volunteer donors have provided long-term disease-free survival for a variable proportion of patients, depending on degree of HLA matching with the donor, patient's disease, disease stage, and age. The number of volunteers in marrow donor registries worldwide has increased to more than 2.5 million. The number of unrelated donor transplants facilitated by the US National Marrow Donor Program alone will exceed 900 this year. Progress in HLA-typing technology results in a more precise definition of donor and recipient matching and new assays have been developed with initial success to measure alloreactive T-cell precursors for selection of donors with less antihost reactivity. Prevention and treatment of graft failure, graft-versus-host disease, opportunistic infections, and Epstein-Barr virus-associated lymphoproliferative disease remain a challenge.
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PMID:Marrow transplantation from unrelated donors. 937 34

Patients undergoing bone marrow transplantation are susceptible to many different bacterial, fungal and viral infections. Among the viral pathogens, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus cause the greatest morbidity and mortality and have been the most common infectious causes of death following the grafting of allogeneic marrow. This great susceptibility to viral infections is due to the immunodeficiency in cellular and humoral immune responses lasting for months to years. Contributing factors are high-dose chemo/radiotherapy, graft-versus-host disease (GVHD) prophylaxis/treatment, GVHD itself, the degree of HLA disparity between donor and recipient and the underlying disease. Defects of T cell helper and cytotoxic functions contribute to the great incidence of viral infections. We described here the kinetic of immunological reconstitution and the role of T cell immunodeficiency. At day 30 to 40 after BMT, a minority of patients had recovery of virus-specific CD8+ T-cell response. Between day 40 and day 90 recovery of deficient CD8+ and CD4+ T cell responses occurred in the majority of the recipients of HLA identical BMT but only in the minority of the recipients of HLA partially incompatible BMT. New approaches should therefore be envisaged either to preserve donor T-cell-mediate immunity or tho accelerate immune reconstitution. Add-back of unmanipulated T-cells, or virus-specific T cells could improve antimicrobial defenses after BMT.
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PMID:[Antiviral immunodeficiency: EBV, CMV, adenovirus]. 943 82

We report a patient who developed breast masses 17 months after a T cell-depleted partially mismatched related donor (PMRD) bone marrow transplant (BMT) for chronic myeloid leukemia. The patient had severe chronic graft-versus-host disease (GVHD) and the masses were due to Epstein-Barr virus (EBV) lymphoproliferative disease (LPD). The patient expired from fungal pneumonia after chemotherapy for the EBV-LPD.
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PMID:Late onset Epstein-Barr virus-associated lymphoproliferative disease after allogeneic bone marrow transplant presenting as breast masses. 948 54

Some of the recent advances in our knowledge of immune recognition have provided new tools to circumvent or reverse some of the major disadvantages of allogeneic bone marrow transplantation (BMT). The pretransplant conditioning regimen produces a major defect in the immune system that greatly favors the occurrence of life-threatening infections, caused particularly by Epstein-Barr virus and cytomegalovirus. However, adoptive transfer of virus-specific cytotoxic T lymphocytes can reconstitute specific immunity and/or cure viral disease in immunocompromised post-BMT patients. The other major drawback of allogeneic BMT is graft-versus-host disease (GVHD). Although potentially detrimental, it is closely associated with an antileukemia reaction (graft-versus-leukemia, GVL). The most direct evidence of the GVL effect has been provided by the efficacy of donor leukocyte infusions (DLI). DLI can induce long-lasting remissions, especially in patients with chronic myeloid leukemia who relapse post-BMT. Although allogeneic cell therapy should still be considered a "naive" form of immunotherapy, work in progress on the identification of leukemia-specific antigens will improve the outcome and enlarge its applications.
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PMID:Adoptive immunotherapy following allogeneic bone marrow transplantation. 950 67

T-cell depletion of bone marrow for allogeneic transplantation is known to increase the risks of Epstein-Barr virus-driven lymphoproliferative disorders that may result in fatal lymphoma, especially with transplants from unrelated or mismatched donors. Over the past 15 years, we have monitored the outcome of 2,582 transplants using CAMPATH-1 (CD52) antibodies to deplete lymphocytes from donor and/or recipient to prevent graft-versus-host disease or rejection. Unlike many other methods of T-cell depletion, CAMPATH-1 antibodies also deplete B lymphocytes. The actuarial risk of lymphoproliferative disease using CAMPATH-1 for depletion of donor lymphocytes was up to 1.3%, hardly different from reported figures for conventional nondepleted transplants. In contrast, the risk in a small group of patients transplanted from unrelated donors using E-rosette depletion was as high as 29%, comparable to other reports of specific T-cell depletion. We conclude that the additional depletion of B cells is beneficial, possibly because it reduces either the virus load or the virus target until the time when T cells begin to regenerate.
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PMID:Risks of developing Epstein-Barr virus-related lymphoproliferative disorders after T-cell-depleted marrow transplants. CAMPATH Users. 953 22

We report two cases of Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (LPD) after allogenic bone marrow transplantation which were conditioned with regimens including antithymocyte globulin (ATG). The first case was a 31 year-old man which severe aplastic anemia who was transplanted from HLA-matched unrelated donor conditioned with total lymphoid irradiation (TLI)/ cyclophosphamide/ATG and prophylactic administration of ganciclovir Grade I acute GVHD improved in response to cyclosporine (CsA). LPD as a polyclonal epipharyngeal mass developed at day +53 and spontaneously regressed along with the withdrawal of CsA. Second case was a 11 year-old boy with acute myelomonocytic leukemia (FAB:M4E). He was transplanted from HLA B locus mismatched mother conditioned with total body irradiation (TBI)/busulfan/L-PAM/ATG. He showed grade IV acute GVHD, which was controlled by steroids and FK-506. LPD as a monoclonal intestinal lymphoma was diagnosed at day +82, and he was unsuccessfully treated with ganciclovir, acyclovir, chemotherapy and transfusions of EBV-specific cytotoxic lymphocytes in addition to discontinuation of immunosuppressants, and died at day +18 due to sepsis and multiple cerebral infarction. Early detection and introduction of appropriate treatment for post bone marrow transplantation LPD is necessary.
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PMID:[Post-transplant EBV-associated lymphoproliferative disorders--report of two cases]. 957 43

Patients treated with BMT are extremely susceptible to infection with blood-borne viruses that can cause liver disease of variable clinical severity, from minimal biochemical changes to fulminant hepatic failure. Facing a patient with liver disfunction after BMT, one must bear in mind that more than one cause of liver disease, of viral and/or non-viral origin, may coexist. Moreover, besides the most important hepatotropic viruses, other agents, like herpesviruses (including CMV, adenoviruses, Epstein-Barr virus) may also be implicated, sometimes causing a life-threatening fulminant hepatitis, due to their cytopatic effect. Liver disease history and viral markers before transplant, together with the accurate assessment of the timing and type of clinical and biochemical deterioration are useful tools for a differential diagnosis. Liver biopsy, if taken in the early posttransplant period, is often difficult to interpret, while in case of liver disease occurring during immunosuppression tapering, histologic examination may discriminate between an exacerbation of viral hepatitis and an acute onset of chronic liver GVHD. While it seems that hepatitis G virus does not cause liver disease, the presence of hepatitis B virus (HBV) or hepatitis C virus (HCV) infection is a matter of concern for its consequences both early after BMT and for long-term survivors. Despite screening for blood and marrow donors for HBV and, more recently, for HCV markers, the rate of post-transplant infection (4% and 4-15% respectively, confirmed in prospective studies) with those viruses indicates that viral hepatitis still remains an important clinical problem in this setting, although the prognosis of chronic HCV and HBV infection appears more benign than expected, especially in children.
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PMID:Infections with hepatotropic viruses in children treated with allogeneic bone marrow transplantation. 963 Mar 33

We report a case of a 16-month-old Wiskott-Aldrich syndrome (WAS) patient with a WASP gene mutation who received human leukocyte antigen (HLA)-matched, unrelated allogeneic bone marrow transplantation (BMT) followed by an Epstein-Barr virus-associated lymphoproliferative disorder (EB-LPD), diagnosed by clinical findings, polymerase chain reaction detection of the EB virus genome, and spontaneous lymphocyte proliferation of donor cell origin. EB-LPD is one of frequent lethal complications in HLA-mismatched or unrelated BMT in this syndrome. Adoptive immunotherapy with donor leukocyte transfusion, including appropriate numbers of CD3-positive T cells, was effective for the EB-LPD, achieving almost complete recovery 1 year later without any findings of graft-versus-host disease.
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PMID:Epstein-Barr virus-associated lymphoproliferative disorder after unrelated bone marrow transplantation in a young child with Wiskott-Aldrich syndrome. 965 36

We report a case of natural killer cell large granular lymphocytic (NK-LGL) leukaemia successfully treated with allogeneic peripheral blood stem cell transplantation (allo-PBSCT). The peripheral blood (PB) revealed an abnormal expansion of LGL that were CD3-, CD16- and CD56+, and had natural killer activity. In situ EBER-1 hybridization of the PB mononuclear cells showed the presence of Epstein-Barr virus (EBV) in the LGL as well as in lymphocytes infiltrating the tonsils and colon. Southern blotting with an EBV-terminal repetitive sequence probe demonstrated clonal proliferation of EBV+ cells. The patient received allo-PBSCT from his HLA-matched sister with a conditioning regimen involving the use of cyclophosphamide and fractionated total body irradiation. The patient promptly recovered trilineage haematopoiesis without graft-versus-host disease, and has been in complete remission without therapy for 10 months since allo-PBSCT, suggesting that allo-PBSCT could eradicate the NK-LGL leukaemic cells.
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PMID:Successful treatment of Epstein-Barr virus-associated natural killer cell large granular lymphocytic leukaemia using allogeneic peripheral blood stem cell transplantation. 967 65


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