Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to explore T-cell functions shortly after allogeneic bone marrow transplantation more fully, IL2- and IL4-dependent proliferation was assessed on CD4+ TCR alpha beta+ T-cell clones derived 4-6 weeks after transplantation. Both allogeneic pooled peripheral blood mononuclear cells and Epstein-Barr virus-transformed B-cell lines (BCL) could function as accessory cells (AC) for PHA activation of T-cell clones. Although minimal clonal proliferation was seen when the T-cell activation signal was BCL+PHA+IL4, a majority of the clones could undergo IL4-dependent proliferation after previous activation with AC+PHA+IL2. For certain clones, IL4 also showed an additive effect with IL2. Thus, IL4 was a growth factor for a majority of the investigated posttransplant T-cell clones, and in vivo modulation of IL4-dependent T-cell functions may thus become a future therapeutic possibility to enhance graft-versus-leukaemia effects in bone marrow transplant recipients.
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PMID:IL2- and IL4-dependent proliferation of T-cell clones derived early after allogeneic bone marrow transplantation: studies of patients with chronic myelogenous leukaemia. 135 May 37

When blood cells are projected into an image plane their contours appear as borderlines of irregular shape with the property of the statistical self-similarity. The dimension D of these cell perimeters may be fractal rather than an integer as in the Euclidean space. The fractal dimension D for different q'order moments was evaluated by means of a probabilistic method after recording EM image profiles of normal peripheral blood mononuclear cells (PBMN) and mature lymphocytes and also of lymphoblasts isolated from humans with acute leukemia or obtained by lectin stimulation in vitro. PBMN cells, CD 4 and CD 8 T-lymphocytes showed a fractal dimension D quite similar among five moments, ranging from 1.23-1.17. Cells of hairy-cell leukemia with highly convoluted morphology displayed D comprised between 1.32-1.36, whereas blasts of T or B acute lymphoblastic leukemia were characterized by a smaller D of 1.11 and 1.13-1.16 respectively. When normal T-lymphocytes were transformed into blasts by lectin PHA stimulation in vitro, the fractal dimension D was significantly reduced and found close to the value recorded on pericellular contour of blasts from acute T-lymphoblastic leukemia.
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PMID:Fractal dimension of pericellular membranes in human lymphocytes and lymphoblastic leukemia cells. 140 12

By using a fluorescence sandwich ELISA for the quantification of soluble human IL-6R, normal human PBMC were found to be induced to release IL-6R into culture supernatant by stimulation with PHA. Furthermore, certain promonocyte cell lines and human T-cell leukemia virus I (HTLV-I)-positive cell lines produced sIL-6R into culture supernatants constitutively. However, this was not found with HTLV-I negative T cell lines and Burkitt's B cell line. In addition, generation of supernatant IL-6R of the promonocyte cell line was significantly increased 27-fold after PMA treatment and sevenfold after infection with HIV. The released IL-6R molecules were characterized as an apparent m.w. of 50 to 55 kDa by both size-exclusion HPLC and immunoprecipitation of the soluble protein with IL-6R-specific mAb followed by SDS-PAGE analysis. Furthermore, increased levels of serum IL-6R were detected in blood donors seropositive for HIV. Moreover, the released IL-6R could bind efficiently to purified rIL-6 on solid phase and suppressed the proliferative responses of PBMC. These results suggest that the release of soluble IL-6R might be linked to regulatory functions of immune responses induced by IL-6 stimulation during normal and human retrovirus-infected cell growth and differentiation.
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PMID:Human soluble IL-6 receptor: its detection and enhanced release by HIV infection. 154 25

In this literature study the possible correlation between GH-therapy and leukemia has been critically evaluated. Two central questions have been studied: 'does leukemia occur more often in GH-deficient children in GH-therapy than in age-related normal individuals' and 'which influences of GH administration upon normal and leukemic leukocytes have been described?'. In some cases leukemia developed in GH-deficient children after GH-therapy. The data have shown a higher incidence of leukemia in the population of children treated with GH (5:100,000) than in the age-related normal population of children (2:100,000). However, hard evidence supporting the hypothesis that GH-therapy could induce leukemia has not yet been found. In vivo studies could not detect enhanced growth of blood cells influenced by GH-therapy. In vitro studies showed that GH either stimulated or did not affect the proliferation of unstimulated lymphocytes of GH-deficient children, normal individuals or leukemia-patients. The same effects occurred in leukemic cell lines. On PHA-stimulated lymphocytes of GH-deficient children and normal individuals both enhancing and inhibiting effects of GH have been found. It is suggested that GH-therapy could improve immunological resistance against tumors by improving Natural-Killer-cell activity. In mice GH seemed to influence lymphocyte-differentiation. In mice also an increase in the frequency of chromosomal aberrations related to GH has been observed. This evaluation suggests that patients, treated with GH-therapy should be carefully followed up. Also, the indication for GH-therapy has to be guarded critically.
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PMID:[Growth hormone therapy and leukemia]. 155 76

Immunostimulatory therapy is at present considered after autologous bone marrow transplantation (ABMT) in order to mimic the allogeneic graft-versus-leukemia effect and thereby reduce the relapse rate. In a pilot study, five adults with acute myeloid leukemia were treated with the new immunomodulator Linomide post-ABMT. Linomide (0.3 mg/kg/week orally) was given in cycles of three weeks followed by three weeks of rest for up to six months. During treatment periods cyclic increases of CD56+CD3- and CD16+ NK cells were observed in parallel with enhanced cytotoxic activity of patient cells against both the NK-sensitive K562 and NK-resistant Daudi cell lines. A cyclic increase of CD14+ monocytic cells was also recorded. The proliferative responses of patient cells to PHA and allogeneic cells (MLC) were enhanced during Linomide therapy. The in vitro production of TNF alpha, IFN gamma, and IL-1 followed the same cyclic increase during treatment periods. Side effects were generally mild, and no harmful effects on engraftment were seen. Linomide therapy after ABMT thus induces a broad immunostimulation that offers a potential benefit with regard to leukemia-free survival.
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PMID:Stimulation of NK cell, T cell, and monocyte functions by the novel immunomodulator Linomide after autologous bone marrow transplantation. A pilot study in patients with acute myeloid leukemia. 156 54

Soluble suppressor factor (SSF), first described in association with HIV-1 infection in vivo, is a molecule(s) capable of inhibiting T cell-dependent immune reactivity. Its relationship to human immunodeficiency virus (HIV) was further defined as supernatants of mononuclear cell cultures from HIV-1-seropositive carriers, CD4+ T lymphocytes infected with HIV-1 in vitro, and a T cell hybridoma incorporating CD4+ lymphocytes from an HIV-1-seropositive individual were shown to elaborate factors with similar activity profiles. These factors were recognized antigenically by certain antibodies directed against epitopes of p15E, a transmembrane protein of murine leukemia virus which shares regions of identity with proteins deduced from human endogenous retroviral envelope transcripts as well as HIV. These reagents precipitated a single-chain, nonglycosylated, nonviral protein of molecular weight 57,000 Da from SSF-producing cells. There was no cross-reactivity with antisera recognizing the IL-2R alpha-chain (CD25) or tumor necrosis factor. This molecule was present in very low levels in PHA-activated T lymphocytes and was upregulated following their infection with HIV-1. Isolation of HIV-linked SSF should permit comparisons with other virion, cellular, and serum inhibitory substances described in AIDS, and perhaps suggest therapeutic strategies.
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PMID:A soluble inhibitor of T lymphocyte function induced by HIV-1 infection of CD4+ T cells: characterization of a cellular protein and its relationship to p15E. 169 8

Deoxycoformycin (DCF) has been reported to cause immediate reduction and dysfunction of T lymphocytes, but the long-term effects on immune functions are still not known. As cytokine production is regulated by T helper-inducer lymphocytes and might represent a parameter for functional integrity of immunocompetent cells, we have measured the production of interleukin-2 (IL-2), tumor necrosis factor (TNF), and interferons (IFN) by peripheral mononuclear cells (PMNC) from 10 patients with hairy cell leukemia 11-24 months after end of therapy with DCF. The patients were in continuous remission at the time of study. Despite an absolute reduction in CD3+ and CD4+ lymphocytes. there were no significant differences in IL-2 or TNF release between patients and controls. Except for a significant reduction in IFN-alpha release stimulated by Newcastle disease virus (NDV), IFN productions induced by other mitogens (phytohemagglutinin, PHA; Concanavalin A, ConA; pokeweed mitogen, PWM) and viral antigens were within normal range. There was also a decrease in proliferative responsiveness to PHA, but responses to ConA, PWM, and other viral antigens were normal. In five of the patients, we have monitored closely the changes in IL-2, TNF, and IFN before, during, and after treatment and could demonstrate a rapid normalization of initially decreased IL-2 release in all cases and also of TNF if the initial production was reduced. This study shows that, even though the absolute number of T lymphocytes and helper cells are reduced in the long-term observation after DCF treatment, the capacity to produce IL-2, TNF, and IFN-gamma was within normal range. Parallel to this observation, no opportunistic infections or frequency of infectious complications occurred in these patients.
Leukemia 1990 Aug
PMID:Long-term effects of 2'-deoxycoformycin treatment on cytokine production in patients with hairy cell leukemia. 169 12

Three predominantly CD8+ CTL lines, TIL 501, TIL 620, and TIL 660, were generated from three HLA-A2+ melanoma patients by culturing tumor-infiltrating lymphocytes in 1000 U/ml IL-2. These tumor-infiltrating lymphocytes lysed 12 of 18 HLA-A2+ autologous and allogeneic melanomas, but none of 20 HLA-A2-negative melanomas. They also did not lyse the MHC class I negative lymphoma-leukemia cell lines, Daudi, K562, or HLA-A2+ non-melanoma cell lines including PHA or Con A-induced lymphoblast, fibroblast, EBV-transformed B cell, Burkitt's B cell lymphoma, and colon cancer cell lines. Autologous and allogeneic melanoma lysis was inhibited by anti-CD3, by anti-MHC class I, and by anti-HLA-A2 mAb, indicating recognition of shared tumor Ag among melanoma cell lines in a TCR-dependent, HLA-A2-restricted manner. Six HLA-A2-negative melanoma cell lines obtained from five HLA-A2-negative patients were co-transfected with the HLA-A2.1 gene and pSV2neo. All 17 cloned transfectants expressing cell surface HLA-A2 molecules, but none of 12 transfectants lacking HLA-A2 expression, were lysed by these three HLA-A2-restricted, melanoma-specific CTL. Lysis of the HLA-A2+ transfectants was inhibited by anti-CD3, by anti-MHC class I, and by anti-HLA-A2 mAb, indicating recognition of shared tumor Ag on transfectants in a TCR-dependent, HLA-A2-restricted manner. These results identify the HLA-A2.1 molecule as an Ag-presenting molecule for melanoma Ag. They also suggest that common melanoma Ag are expressed among melanoma patients regardless of HLA type. These findings have implications for the development of melanoma vaccines that would induce antitumor T cell responses.
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PMID:Shared human melanoma antigens. Recognition by tumor-infiltrating lymphocytes in HLA-A2.1-transfected melanomas. 172 79

Human chromosomes contain about one million copies of dispersed repeats of the Alu family which are distributed non-randomly. In this study we have compared the pattern of hybridization of tritiated Alu-probes on chromosomes of PHA-stimulated lymphocytes of normal donors and of non-stimulated bone marrow cells of acute leukemia patients, and found regular differences in this pattern over some chromosome bands (3q26, 8p11-p12, 14q24, 15q21, 6q22) between normal individuals and leukemia patients. These data were interpreted as indicative of somatic variation of the Alu family in acute leukemia. Possible mechanisms of the variation and the role of the Alu family in chromosome rearrangements in neoplasia are discussed.
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PMID:Alu family variations in neoplasia. 174 66

Cytotoxic T lymphocyte precursor (CTLp) frequency assays were examined in patients with chronic myeloid leukaemia (CML) following bone marrow transplantation (BMT) using recipient lymphocytes or CML cells as targets in a 51Cr release cytotoxicity assay. Eighteen patients were studied; 11 received marrow from a fully HLA A, B and DR matched sibling donor, and six from matched unrelated donors or a partially matched sibling (one patient). Two of the unrelated donor transplant recipients received marrow depleted of T lymphocytes, and the remainder received unmanipulated marrow and cyclosporin with or without methotrexate as prophylaxis against graft-versus-host disease (GVHD). Donor cells tested before BMT did not generate CTL against the patients' leukaemia, but up to 9 months after BMT a low frequency of CTLp directed against the patients' CML cells (Lk-CTLp) was detected in all patients. The Lk-CTLp frequency was significantly lower than the frequency of CTLp directed against the recipients' PHA transformed pretransplant lymphocytes (Ly-CTLp) (p less than 0.05). Lk-CTLp showed MHC restricted cytotoxicity and did not demonstrate cytotoxicity in an NK assay. The Lk-CTLp frequency correlated with both GVHD severity and relapse: severe GVHD was only seen with Lk-CTLp frequencies greater than 1:400,000, while leukaemic relapse was only observed in two patients with Lk-CTLp frequencies less than 1:400,000. These results show that a low frequency of alloreactive cells of presumed donor origin with cytotoxic potential against residual leukaemia normally circulate after BMT. Their relationship with the graft-versus-leukaemia phenomenon and their cross-reaction with GVHD reacting cells remain to be determined.
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PMID:Graft-versus-leukaemia following allogeneic bone marrow transplantation: emergence of cytotoxic T lymphocytes reacting to host leukaemia cells. 175 22


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