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)

We describe here a case of T-cell lymphocytic leukemia (T-CLL) which coexpressed CD4 and CD45RA cell-surface antigens and functioned as suppressor inducer cells. The patient, an 81 year-old man, had massive generalized lymphadenopathy. His hemoglobin was 9.4g/dl, the platelet count 94,000, and the WBC was 895,000/microliters with 98% abnormal lymphoid cells. He had massive hepatosplenomegaly. Serum LDH was elevated to 3,990 u/l. The T-CLL cells coexpressed antigens detected by MAbs CD2, CD3, CD4, CD5, Ti(TcR alpha/beta; WT31) CD45 and CD45RA, but did not express any other antigens including CD1, CD8, CD29, and TCR gamma/delta, Ti gamma A and TQ-1. The cell-surface phenotypes of the cultured cells established by utilizing recombinant interleukin 2 were basically the same as those of the uncultured peripheral blood lymphoid cells. Both the peripheral blood and cultured cells clearly showed gene rearrangement for T cell receptors, TcR beta and TcR gamma. No association with human T-cell leukemia virus-1 (HTLV-1) was found by means of electron microscopic studies or the application of MAbs to p19 and p24 of HTLV-1. No anti-HTLV-1 antibody was detected. By the means of two color fluorescence, it was clearly demonstrated that the leukemic cells possessing CD4 in the peripheral blood and cell cultures coexpressed CD45RA, but did not express either CD29 or TQ-1. In vitro immunoglobulin synthesis by normal T and B cells was remarkably reduced in the presence of CD8+ T and leukemic cells. This suggests suppressor inducer T cell activity for the leukemic cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:CD4+, CD45RA+, CD29- T-cell lymphocytic leukemia functioning as T suppressor inducer for B-cell immunoglobulin synthesis. 769 6

The expression of CD45 RA/RO antigen was investigated in neoplasms including cases expressing CD7 antigen as the sole pan-T antigen (n = 8), T-lineage acute lymphoblastic leukemia (ALL)/lymphoblastic lymphoma (LBL) at various stages of differentiation (n = 32), peripheral stage T-lineage leukemia (n = 10) and adult T-cell leukemia (ATL) (n = 14). The p56lck gene expression was also investigated in selected cases. The expression pattern of CD45 RA/RO antigen was defined as of RA, mixed, or RO type. All but one CD7+ CD5- CD2- case were of the RA type. The CD7+ CD5+ CD2- prothymic stage included seven RA and one mixed type cases. One CD7+ CD5- CD2+ case was of the RA type, but the other was of the RO type. The CD7+ CD5+ CD2+ prothymic stage included three RA and four mixed type cases. All seven CD3- CD4+ CD8+ (double-positive) thymic cases were of the RO type. The CD3+ CD4+ CD8+ (triple-positive) stage included two RO and three mixed-type cases. One CD3+ CD4+ CD8- late thymic case was of the mixed type. The peripheral stage cases included five RA, three RO, and two mixed type cases. All ATL cases were of the RO type. The expression of p56lck gene in the prothymic stage was less marked than that in the thymic stage. On the basis of these results, the following sequence of pattern of the CD45 RA/RO antigen expression along with T-lineage differentiation was reconstructed: prothymic stage [RA and mixed type]-->double-positive thymic stage [RO type]-->triple-positive thymic stage [RO and mixed type]-->peripheral stage [RA, mixed, and RO type]. While one RO-type CD7+ CD5- CD2- and one RO-type CD7+ CD5- CD2+ cases were not in accord with this sequence, the pattern of CD45 RA/RO antigen expression in most of T-lineage neoplasms could be determined by the respective stage of differentiation. The poor expression of the p56lck gene by the prothymic blasts compared with the thymic blasts may be related to the expression pattern of the CD45 RA/RO molecules, which exhibits phosphatase activity. The consistent RO-type expression in the ATL cases may reflect the activated status of the neoplastic T cells due to the presence of the HTLV-I gene. Alternatively, the target cells for HTLV-I-induced neoplastic transformation may possible be of the RO type.
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PMID:Expression pattern of CD45 RA/RO isoformic antigens in T-lineage neoplasms. 774 Nov 40

In the present study we investigated the membrane expression of selectin ligands (CD15/Le(x), CDw65/VIM2, CD15s/sLe(x), beta 2 integrins (CD11a/LFA-1, CD11b/Mac-1) and CD45 phosphatase isoforms (CD45RA, CD45O) on leukaemic cells from 28 patients with acute myeloid malignancies cultured with and without all-trans retinoic acid (ATRA). Within each adhesion system. ATRA was able to differentially regulate distinct molecules. Furthermore, it was able to exert effects specific for acute promyelocytic leukaemia (APL) blast cells, as well as to induce a series of non-cytotype-restricted phenotypic changes. An impressive feature of ATRA induction was a simultaneous increase in the expression of CD15, CDw65 and CD11b on leukaemic promyelocytes. The sialylated antigen CD15s, however, showed results independent from the other two carbohydrates (CD15 and CDw65), suggesting a differential enzymatic regulation within the selectin ligands system. In spite of the well-recognized expression of CD11a throughout all stages of normal myeloid differentiation, APL blast cells were found to virtually lack LFA-1 expression. Moreover, ATRA was unable to promote an up-regulation of this antigen in APL, while inducing a frequent down-modulation in non-APL cases constitutively expressing this antigen. In APL cases ATRA generated an asynchronous phenotype (CD15+, CDw65+, CD11b+, CD11a-), undetectable on normally maturing myeloid cells, but consistent with the concept that incomplete differentiation, in terms of surface molecule expression, can be sufficient to obtain therapeutic results.
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PMID:All-trans retinoic acid promotes a differential regulation of adhesion molecules on acute myeloid leukaemia blast cells. 780 67

The expression of purinergic receptors on human T-cells was investigated and the receptors were shown to be functionally coupled to intracellular signals in two out of eight T-leukaemia cell-lines. Addition of adenine nucleotides resulted in mobilization of intracellular Ca2+ in HPB-ALL cells and a cell line (CB1) recently isolated from a patient with T-acute lymphoblastic leukaemia. Of a range of nucleotides tested only ADP and ATP elevated intracellular levels of Ca2+, with ADP being the more potent agonist. Ca2+ mobilization by ATP was accompanied by increased inositol phosphate production and was blocked by the purinergic receptor antagonist, Reactive Blue 2, indicating that ATP was interacting with a P2y receptor. Intracellular Ca2+ release triggered by ADP was independent of both inositol phosphate production and protein tyrosine phosphorylation. Expression of the transmembrane phosphotyrosine phosphatase, CD45, had no effect on ADP-stimulated Ca2+ mobilization. Our results show that functional P2y receptors can be expressed on T-cells, and also identify a novel T-cell ADP receptor. Signals mediated by these purinergic receptors could play important roles in modulating T-cell function.
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PMID:Mobilization of intracellular Ca2+ by adenine nucleotides in human T-leukaemia cells: evidence for ADP-specific and P2y-purinergic receptors. 781 79

v-mpl is a constitutively activated, truncated form of a cytokine receptor that has been transduced in a murine retrovirus, the myeloproliferative leukemia virus (MPLV). Expression of this oncogene results in the factor-independent proliferation of myeloid, erythroid, megakaryocytic, and mast precursor cells, which retain the ability to differentiate. However, no lymphoid disease was ever reported. To determine whether MPLV could infect and transform very early B cells and their precursors (BCPs), lymphoid long-term bone marrow cultures were infected with a helper-free MPLV. Within 3 wk after infection, highly proliferating BCPs could be isolated. These cells were able to clone spontaneously in semi-solid cultures, grown in the absence of feeder cell layer or exogenous growth factor and rapidly produced tumors after s.c. injection into synegic irradiated mice. In addition, MPLV transformation of pre-B cells led to the induction of an autocrine activity. Immunophenotypic and molecular analysis indicated that MPLV transformed early pro-B, pro-B, and pre-B cells, according to the expression of HSA, CD43, B220, Thy1, s-IgM and BP1 Ags, and to the rearrangements of Ig genes. Interestingly, MPLV-transformed BCPs expressed Mac1 Ag without acquiring further characteristics of macrophagic differentiation. Although the v-mpl cytoplasmic domain is devoid of tyrosine kinase consensus sequence, MPLV-transformed pre-B cells contained a major approximately 105-kDa tyrosine-phosphorylated protein that was not detected in uninfected cells or in cells transformed by the Abelson viral oncogene (v-abl). These results demonstrate that, like v-abl, the truncated cytokine receptor v-mpl is able to transform BCPs in vitro and suggest that the oncogenic transformation of BCPs by either v-mpl or v-abl use different pathways.
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PMID:In vitro transformation of murine pro-B and pre-B cells by v-mpl, a truncated form of a cytokine receptor. 783 43

A myeloma cell line (KHM-11) was established from the pleural effusion of a patient with IgA-kappa type aggressive myeloma with high serum lactate dehydrogenase who was extremely resistant to vincristin, adriamycin and dexamethasone combination therapy (VAD). The morphology of fresh tumor cells and KHM-11 was plasmablast according to Greipp's criteria. In addition to the expression of regular plasma cell antigens, CD38 and PCA-1, CD45 was found on both fresh cells and KHM-11. Other T- or B-cells antigens, such as CD2, 4, 8, 19, and 20 were negative. Cytoplasmic immunoglobulin kappa light chain in KHM-11 was found by flowcytometry. Southern blot analysis revealed that fresh sample and KHM-11 shared the same immunoglobulin gene rearrangement. IL-6 was found in the culture supernatant of KHM-11, and this supernatant stimulated the growth of this cell line, indicating an IL-6 autocrine mechanism. These findings indicate that KHM-11 is a CD45-positive immature plasma cell line. As far as we know, there is no report of CD45-positive myeloma cell line. KHM-11 should be a useful tool for understanding not only the pathogenesis of aggressive multiple myeloma with high LDH but also for understanding the mechanism which underlies the terminal differentiation of B-cells.
Leukemia 1994 Oct
PMID:Establishment of a CD45-positive immature plasma cell line from an aggressive multiple myeloma with high serum lactate dehydrogenase. 793 74

The differentiative capacity of a unique haematopoietic cell type has been investigated. These cells have been found to be a common target in vitro to infection and immortalization by radiation leukemia viruses (RadLVs). Many continuous lines of these cells have been generated. Since RadLV retroviruses are known to be strictly T-cell-tropic in vivo, we have questioned whether these cells are precursors of T cells. To this end, the RadLV-induced C1-V13D cell line has been inoculated into thymus of sublethally irradiated syngeneic CBA/H mice and tested for capacity to proliferate and differentiate, i.e. express T-cell markers. When inoculated in high number, C1-V13D cells can induce a thymic tumour within 14 to 21 days. Expression of T-cell markers on these cells was determined by fluorescence-activated cell sorting (FACS) analysis, after gating out C1-V13D cells on the basis of their high 90 degree scatter and their high forward scatter. They can also be distinguished by their unique expression of RadLVgp70 envelope (env) protein, B220, CD44, and aberrant expression of a class I epitope. Explanted primary thymomas from many animals showed no evidence of T-cell marker expression on C1-V13D cells upon reisolation. However, when C1-V13D was further passaged intrathymically, there was clear expression of Thy-1, CD4, CD8, and TCR-alpha beta on C1-V13D cells reisolated from these tumours. Two-colour FACS analysis and fluorescent antibody staining have confirmed the acquisition of T-cell surface markers by C1-V13D cells growing in this environment. Northern analysis confirmed endogenous expression of T-cell receptor beta chain genes in C1-V13D cells isolated after the third passage. All data indicate that RadLV preferentially infects a unique haematopoietic precursor cell in spleen which can differentiate along the T lineage once located within the thymic environment. The cell lines described here represent valuable models for studying T-cell differentiation from lymphoid stem cells, and for dissecting the early events in leukemogenesis.
Leukemia 1993 Aug
PMID:T-cell differentiative capacity of haematopoietic stem cells immortalized in vitro with radiation leukemia virus. 810 19

Quantitative expression, i.e. absolute number of monoclonal antibody molecules bound per cell, was evaluated for CD24 and CD45 by flow cytometry with standards of fluorescence intensity on a panel of normal and neoplastic B cells. The CD24 antigen was expressed at homogeneous high level in fetal bone marrow and liver. Its density decreased progressively in the other normal tissues in parallel with the B-cell maturation. The ratio between CD24 density measured on fetal bone marrow B cells and that seen on adult peripheral B cells was 6:1. The CD45 antigen density was lower on fetal bone marrow cells than in the more mature stages. Fetal spleen lymphocytes and all the mature B lymphocytes displayed the same CD45 density than that seen on normal adult peripheral T cells. The CD24/CD45 antigen density ratio was precisely related to the stage of B-cell maturation. The same pattern of variation of CD24 and CD45 antigen density was seen on B-cell neoplasias, with a significantly higher value of CD24 and lower value of CD45 in acute lymphoblastic leukemias than in chronic malignancies. CD24 and CD45 antigen levels were frequently out of the range observed in the corresponding normal population. Among ALL patients, a low CD24/CD45 antigen density ratio was associated with a good prognosis. These data confirm the interest of an absolute quantitative study for widely distributed antigens.
Leukemia 1994 Mar
PMID:Quantification of CD24 and CD45 antigens in parallel allows a precise determination of B-cell maturation stages: relevance for the study of B-cell neoplasias. 812 45

The cell line described here was established for a 50-year-old male patient with rapidly progressive non-Hodgkin's lymphoma whose marrow was diffusely infiltrated with large granular lymphocytes (LGL). Immunophenotyping of marrow blasts and peripheral lymphocytes was positive for CD56, CD2 and CD7, and negative for CD3. Cytotoxicity of peripheral blood mononuclear cells at an effector: target (E:T) cell ratio of 50:1 was 79% against K562 cells and 48% against Daudi cells. To establish the line, cells from the peripheral blood were placed into enriched alpha medium containing 12.5% fetal calf serum, 12.5% horse serum, 10(-4) M beta-mercaptoethanol and 10(-6) M hydrocortisone. Growth of the line (termed NK-92) is dependent on the presence of recombinant IL-2 and a dose as low as 10 U/ml is sufficient to maintain proliferation. Conversely, cells die within 72 h when deprived of IL-2; IL-7 and IL-12 do not maintain long-term growth, although IL-7 induces short-term proliferation measured by 3H-thymidine incorporation. None of the other cytokines tested (IL-1 alpha, IL-6, TNF-alpha, IFN-alpha, IFN-gamma) supported growth of NK-92 cells which have the following characteristics: surface marker positive for CD2, CD7, CD11a, CD28, CD45, CD54, CD56bright; surface marker negative for CD1, CD3, CD4, CD5, CD8, CD10, CD14, CD16, CD19, CD20, CD23, CD34, HLA-DR. DNA analysis showed germline configuration for T-cell receptor beta and gamma genes. CD25 (p55 IL-2 receptor) is expressed on about 50% of all cells when tested at 100 U/ml of IL-2 and its expression correlates inversely with the IL-2 concentration. The p75 IL-2 receptor is expressed on about half of the cells at low density irrespective of the IL-2 concentration. NK-92 cells kill both K562 and Daudi cells very effectively in a 4 h51-chromium release assay (84 and 86% respectively, at an E:T cell ratio of 5:1). The cell line described here thus displays characteristics of activated NK-cells and could be a valuable tool to study their biology.
Leukemia 1994 Apr
PMID:Characterization of a human cell line (NK-92) with phenotypical and functional characteristics of activated natural killer cells. 815 60

In the present study, we explored the suitability of a new cell fixative (ORTHO PermeaFix, OPF) for the detection by flow cytometry of intracellular molecules while preserving the cell surface immunoreactivity, scatter features and morphology. The effect of OPF was investigated on whole blood of ten normal donors, and on separated blasts of 17 leukemic patients. OPF fixation for 45 min to 24 h maintained the morphology of lymphoid cells with minimal cellular distortion and scatter changes, and only slightly modified cell surface immunoreactivity. For at least 1 week following fixation, the cells were still suitable for immunostaining with monoclonal antibodies that recognize the main lymphoid populations. These included CD3, CD4 and CD8 for T-cell subsets, CD19 and CD16 for B lymphocytes and NK cells, and CD45 for leukocyte common antigen (LCA). The OPF fixation of leukemic cells allowed the simultaneous detection of nuclear TdT in conjunction with membrane CD19, and with membrane and/or cytoplasmic CD22 in common-ALL, as well as with cytoplasmic CD3 in T-ALL cases. Our findings suggest that with the introduction of this new fixative into the routine laboratory service, a number of convenient and practical arrangements can be made which increase the efficiency of immunodiagnosis. Small laboratories with no inhouse flow-cytometric facilities can now accumulate OPF-treated whole blood samples for at least 3-4 days and send these to reference laboratories. In addition, the immunodiagnosis of acute leukemia is greatly facilitated by combination staining for membrane and intracellular antigens both at diagnosis and when the analysis of minority populations is warranted for detecting minimal disease.
Leukemia 1994 Apr
PMID:Detection of membrane and intracellular antigens by flow cytometry following ORTHO PermeaFix fixation. 784 23


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