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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to evaluate the effectiveness and reproducibility of T cell depletion in human leukocyte antigen (HLA)-matched bone marrow graft to prevent graft-v-host disease (GVHD), our multicentric study (nine different centers) investigated 62 consecutive patients with poor prognosis leukemia or hematosarcoma from June 1984 to November 1985. The data were updated October 1, 1986, and the mean follow-up was 18 +/- 4.3 months. T cells were depleted with a combination of 3-pan-T cell monoclonal antibodies (CD2 "D66"; CD5 "A50"; CD7 "I21") with a single incubation of rabbit complement (C'). The average number of T cells infused was 0.66 X 10(6) +/- 0.56/kg body weight. Twenty-six patients received chemoprophylaxis for GVHD, 16 received methotrexate, and ten received cyclosporin A. Only a single case of severe (greater than grade II) GVHD was observed, yet the incidence of graft failure was 19%. Factors that might have influenced the occurrence of graft failure appear to be the lack of radiotherapy in the conditioning regimen; the conditioning regimen itself (fractionated total body irradiation [TBI], 12 Gy, v single dose is better than TBI, 10 Gy, but still not statistically significant); and the age of the patients (high-risk after 30 years of age). In contrast, neither the number of nucleated cells reinfused nor the level of T cell depletion (provided the T cells were below critical numbers) seemed to have an influence, nor did chemoprophylaxis for GVHD or splenectomy in chronic granulocytic leukemia (CGL) patients. The survival of graft failure patients was very poor (one of 11; survival at 15 months of the initial graft). Thus, our study demonstrates the reproducibility and high effectiveness in preventing GVHD by immunodepletion of T cells in a large-scale multicentric assay, in which compliance with the protocol of immunodepletion was reasonably good. This study thus provides interesting clues to overcoming graft rejection.
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PMID:Prevention of graft-versus-host disease in HLA-matched bone marrow transplantation for malignant diseases: a multicentric study of 62 patients using 3-pan-T monoclonal antibodies and rabbit complement. 354 17

This article compares the outcome of 14 patients with primary refractory acute leukemia who underwent bone marrow transplantation from human leukocyte antigen (HLA)-identical donors with that of 18 age-matched control patients who received chemotherapy. Complete clearing of leukemia was seen in all 14 transplanted patients. Five of the transplanted patients are alive 98 to 1790 days posttransplant, and four are free of leukemia. Nine patients have died, eight with severe graft-versus-host disease associated with interstitial pneumonia or systemic infections and one with relapse from chemotherapy-associated infections. Engraftment was seen in all patients. Severe graft-versus-host disease (grades III and IV) was seen in ten patients and resolved in three patients following high-dose corticosteroid treatment. Three of the 18 control patients are alive, none of them in complete remission. It appears that the combination of piperazinedione and total-body irradiation followed by allogeneic transplant is effective induction treatment for primary refractory acute leukemia and will be considered in the future as first salvage treatment for patients failing induction treatment.
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PMID:Allogeneic bone marrow transplantation for acute leukemia refractory to induction chemotherapy. 389 57

Bone marrow transplantation is now an accepted form of therapy for many hematologic disorders including aplastic anemia, genetically determined diseases and malignant diseases, particularly leukemia, and for rescue of patients given intensive chemoradiotherapy for malignant disease. The donor may be a healthy identical twin, a family member or even an unrelated person. Selection is made on the basis of human leukocyte antigen tissue typing. Intensive chemoradiotherapy is used to suppress patients' immune systems to facilitate engraftment and destroy diseased marrow. Transfusion of platelets, erythrocytes and granulocytes (or all of these), antibiotic coverage and protection from infection are necessary during the pancytopenic period. Use of a Hickman catheter facilitates maintenance of adequate nutritional intake and provides easy access for drawing blood and intravenous administration. Survival rates vary considerably depending on a patient's disease, clinical state and age. Patients with aplastic anemia transplanted early in the course of their disease have a survival rate of approximately 80%. Patients with acute lymphoblastic leukemia are usually transplanted in a second or subsequent remission and have a survival rate of 25% to 40%. Patients with acute nonlymphoblastic leukemia in remission have survivals ranging from 45% to 70%. More than 200 patients in the chronic phase of chronic granulocytic leukemia have been transplanted with survival ranging from 50% to 70%. Complications of marrow transplantation include marrow graft rejection, graft-versus-host disease, immunologic insufficiency and the possibility of recurrence of the leukemia. The risk of death from these complications must be balanced against the possibility of cure.
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PMID:Overview of marrow transplantation. 391 95

In order to investigate the genetic background of leukemogenesis of two brothers with acute myelogenous leukemia (AML), they and their family members were studied genetically, immunologically, virologically, and cytogenetically. Their parents were first cousins once removed and had the same or a very close type of human leukocyte antigen (HLA) and blood groups. In all five non-leukemic family members the immunoglobulin G (IgG) level was elevated, and in two healthy siblings the IgM level was beyond the normal range. The RNA reverse transcriptase activity in serum of the younger brother (Case 2) with AML was elevated. A cytogenetic study of the family revealed polymorphism of 1qh+. Based on these findings, we discuss the genetic and environmental factors of familial leukemia.
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PMID:Familial acute myelogenous leukemia associated with RNA virus and polymorphism of 1qh+. 616 26

The human leukocyte antigen (HLA) frequencies and antigen sharing were studied in 14 couples with unexplained infertility. There were no significant differences in the frequency of HLA-A, B, C, or DR antigens, as compared with normal control subjects. Furthermore, the degree of HLA sharing did not deviate from that theoretically expected. An increased frequency of HLA-DR sharing, as compared with the expected frequency, was observed in a control group consisting of parents of children with leukemia. When infertile spouses were tested for mixed lymphocyte culture reactivity, there were no indications of an altered reactivity, as compared with control subjects.
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PMID:Human leukocyte antigens group A in couples with unexplained infertility. 622 22

CD8+ T cells were freshly isolated from a human T-cell leukemia virus type I (HTLV-I)-infected patient with tropical spastic paraparesis. These cells, which were specific for HTLV-I Tax, simultaneously recognized a minimum of five, and possibly as many as seven, distinct peptide epitopes within the protein. A further Tax epitope was recognized after a short period of culture without exogenous peptide stimulation. All but one of these epitopes were clustered in the N-terminal third of Tax, and one of the epitopes was clearly immunodominant on two separate occasions of testing. Recognition of the immunodominant epitope was restricted by human leukocyte antigen (HLA) B15, and recognition of all the others was by HLA A2. Similar patterns of cytotoxic T lymphocyte recognition of the HLA A2-restricted Tax peptides in two healthy HTLV-I-seropositive individuals, each of whom carried the HLA A2 allele, were observed.
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PMID:Circulating anti-Tax cytotoxic T lymphocytes from human T-cell leukemia virus type I-infected people, with and without tropical spastic paraparesis, recognize multiple epitopes simultaneously. 751 53

Adult T cell leukemia (ATL) cells show the decreased expression of T cell receptor (TCR)/CD3 complex on their surfaces in vivo. It is well known that excess amounts of antigen modulate TCR/CD3 complex on antigen-specific T lymphocytes. We hypothesized that antigen receptor of ATL cells was down-regulated with some antigenic stimulation in vivo, which might play an important role in leukemogenesis. In order to test this possibility, we studied whether the fresh ATL cells from three cases would respond to autologous and allogeneic lymphoid cell lines. In two of three cases, ATL cells could proliferate in the presence of autologous cell lines. In one case, this proliferation could be completely inhibited by anti-CD3 and anti-human leukocyte antigen (HLA)-DQ monoclonal antibodies, indicating that ATL cells recognized self HLA-DQ. In another case, the proliferation was suppressed by anti-CD3 and HLA-DR antibodies. These findings showed that ATL cells of some cases were derived from autoreactive T lymphocytes and such stimulation via TCR/CD3 complex plays an important role in the leukemogenesis of ATL in vivo.
Leukemia 1995 Aug
PMID:ATL cells recognize self class II HLA antigens: implication to leukemogenesis. 764 22

The presence of a high number of activated T cells in the bloodstream and spontaneous proliferation of peripheral blood mononuclear cells in vitro are striking characteristics of human T-cell leukemia virus type I (HTLV-I) infection. The HTLV-I regulatory protein Tax and the envelope protein gp46 have been implicated in mediating the activation process. In this study, HTLV-I-producing cell lines and purified virus from the cell lines were examined for the ability to activate peripheral blood lymphocytes (PBLs) and Jurkat cells. Antisera and monoclonal antibodies against several cellular adhesion proteins involved in T-cell activation and against viral proteins were used to identify which molecules may be participating in the activation process. First, neither virus from a T-cell line, MT2, nor virus produced from the human osteosarcoma cell line HOS/PL was able to induce PBLs to proliferate. In contrast, both fixed and irradiated HTLV-I-producing T-cell lines induced proliferation of PBLs; HOS/PL cells did not activate PBLs. Second, HTLV-I-positive T-cell lines were capable of activating interleukin-2 mRNA expression in Jurkat cells. Induction of interleukin-2 expression was inhibited by anti-CD2 and anti-lymphocyte function-associated antigen 3 (LFA-3) monoclonal antibodies but not anti-human leukocyte antigen-DR, anti-CD4, anti-LFA-1, or anti-intercellular adhesion molecule 1. Similar results were obtained with PBLs as the responder cells. Furthermore, monoclonal antibodies and antisera against various regions of the HTLV-I envelope proteins gp46 and gp21 as well as p40tax did not block activation. These data indicate that HTLV-I viral particles are not intrinsically mitogenic and that infection of target T cells is not necessary for activation. Instead, the mitogenic activity is restricted to virus-producing T cells, requires cell-to-cell contact, and may be mediated through the LFA-3/CD2 activation pathway.
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PMID:The mitogenic activity of human T-cell leukemia virus type I is T-cell associated and requires the CD2/LFA-3 activation pathway. 768 60

Eighty consecutive patients were transplanted with human leukocyte antigen (HLA)-identical sibling marrow for acute myelogenous leukemia (AML, N = 29), acute lymphoid leukemia (ALL, N = 23), or chronic myelogenous leukemia (CML, N = 28). Donor marrow was depleted of lymphocytes using counterflow centrifugation. Median age of the recipients was 31 years. Pretransplant conditioning consisted of cyclophosphamide and fractionated total body irradiation (TBI). Graft failure occurred in 4 of 77 evaluable patients (5%). The probability of acute graft-versus-host disease (GVHD) > or = grade 2 at day 100 after transplantation was 15%. The projected 3-year estimate of extensive chronic GVHD was 12%. The projected 3-year probability of relapse was 30% in transplants for AML in first complete remission (CR1), 35% after transplantation for ALL in CR1, and 38% after transplantation for CML in first chronic phase (CP1). The projected 3-year probability of leukemia-free survival (LFS) was 56% after transplantation for AML-CR1, 42% in patients transplanted for ALL-CR1, and 49% after transplantation for CML-CP1. The chance of relapse was significantly reduced in a cohort of 72 standard risk patients conditioned with a regimen intensified by the addition of anthracyclines. This resulted in DFS at 4 years after BMT of 63% compared to 39% in a historical control group. Enrichment of the donor marrow with NK-cells did not increase the incidence of GVHD, but did neither decrease the relapse rate after BMT. In bone marrow transplantation for leukemia, counterflow centrifugation is a useful technique for the prevention of GVHD. Further efforts should be made to reduce relapse-rate, particularly in high risk patients.
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PMID:Allogeneic bone marrow transplantation for leukemia with marrow grafts treated by counterflow centrifugation. 812 52

A novel interleukin-2 (IL-2)-dependent T-cell line, WHN2, was established from a patient with adult T-cell leukemia (ATL) not associated with human T-cell leukemia virus type I (HTLV-I). Neither the original leukemic cells nor the WHN2 cells showed proviral integration in their cellular DNAs by Southern blot analysis. The surface phenotype showed that both the original leukemic cells and the WHN2 cells had a common phenotype of ATL, i.e., positive for CD2, CD4, human leukocyte antigen DR (HLA-DR) and CD25, but negative for CD8, a characteristic of helper/inducer T-cells. Most of the chromosomal abnormalities of the original leukemic cells were maintained in the WHN2 cell line. Furthermore, Southern blot analysis of the T-cell receptor beta-chain gene rearrangement revealed that the original leukemic cells and WHN2 cell line had identical patterns, suggesting that the WHN2 cell line was truly derived from the original leukemic cells. Dose-dependent growth on IL-2 was demonstrated, and at the maximal stimulation, the number of cells doubled within three days. This IL-2-dependent growth was inhibited by the simultaneous existence of anti-IL-2 receptor alpha and beta chain antibodies. These results indicate that the character of the WHN2 cell line is similar to that of the cell lines derived from ATL associated with HTLV-I. Thus, the HTLV-I-negative ATL cell line, WHN2, should be useful in the comparative study of the pathogenesis of ATL associated with or without HTLV-I.
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PMID:Novel interleukin-2 dependent T-cell line derived from adult T-cell leukemia not associated with human T-cell leukemia virus type I. 839 Apr 25


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