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)

A permanent cell line, LEF1, has been established from the cells of an adult suffering from a Philadelphia positive acute lymphoblastic leukemia. The LEF1 cell line was obtained by maintaining peripheral blood cells from the patient in culture on a fibroblast feeder; subsequently, an autonomously growing cell population, independent of that feeder layer, developed. The karyotype of the cell line, 46, t(9;22)(q34;q11), was different from the karyotype at diagnosis which had 53 chromosomes and two Philadelphia chromosomes. Furthermore, compared with the initial leukemic blasts, the immortalized cell had three differences in surface phenotype (CD23+, CD11b-, CD10-). However, molecular studies indicated that the breakpoint in the 3' part of the first intron of the BCR gene was unchanged, confirming the leukemic origin of LEF1. The cell line was shown to be Epstein-Barr virus negative.
Leukemia 1990 May
PMID:A new Ph1+, bcr cell line derived from a patient with ALL-L1 gained autonomy in culture concomitant to CD23 expression. 214 94

We have analyzed the configuration of the immunoglobulin heavy (IgH) chain gene and the T cell receptor (TCR) chain (beta, gamma, and delta) genes in a group of 22 leukemia patients with the Philadelphia (Ph) chromosome. The group consisted of 14 patients with chronic myelogenous leukemia in blast crisis (CML-BC) and eight with Ph-positive acute leukemia (Ph + AL); these diagnoses were based on hematologic and cytogenetic features. In CML-BC patients, an IgH joining region rearrangement was detected only in patients with CD10 expression; TCR-beta, -gamma, or -delta rearrangements were associated with IgH involvement. In contrast, five of the eight Ph+ AL patients had breaks within the major breakpoint cluster region (M-BCR), and four of them had IgH involvement. Of the remaining three Ph+ M-BCR nonrearranged AL patients, only one showed IgH rearrangement. In addition, TCR-beta involvement was sometimes detected in Ph+ AL patients (two of the eight patients) with or without rearranged M-BCR, and no PH+ AL case displayed rearranged TCR-gamma. These findings suggest that genotypic changes in CML-BC are usually associated with phenotypic results of the neoplastic cells: the expression of CD10 in CML-BC patients is accompanied by the involvement of IgH with frequent TCR rearrangements which possibly are due to the common recombinase activity. On the other hand, the mechanism of the involvement of IgH in Ph+ AL patients without rearranged M-BCR seems different from that observed in Ph+ leukemia patients with rearranged M-BCR, although TCR involvement could occur whether or not the leukemia cells had a rearranged M-BCR in Ph+ AL patients.
Leukemia 1990 Aug
PMID:Immunoglobulin and T cell receptor gene rearrangements in Philadelphia chromosome-positive leukemia: a different involvement pattern in blast crisis and acute leukemia. 214 95

The cell-surface neutral endopeptidase 3.4.24.11 (NEP) activity of the common acute lymphoblastic leukaemia antigen (CALLA) cleaves diverse peptide mediators at specific sites and it has been postulated that it regulates immune responses. The concentration of NEP was quantified in detergent extracts of synovial tissues by the percentage hydrolysis of [3H-D-Ala]-Leu enkephalin/hr/100 mg of tissue. The synovial tissue concentration of NEP was higher in all patients with rheumatoid arthritis (n = 7; group mean +/- SD = 29.4 +/- 20.2%), and was higher with degenerative joint disease (n = 6 of 8; group mean +/- SD = 11.9 +/- 10.4%) than with traumatic arthropathy (n = 3; 1.1 +/- 0.7%). The lack of direct relationship between synovial tissue NEP concentration and leukocytic infiltration suggests that the cellular source of NEP may be synoviocytes or fibroblasts, and that NEP may have distinctive pathogenetic roles in human arthritis.
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PMID:Elevated synovial tissue concentration of the common acute lymphoblastic leukaemia antigen (CALLA)-associated neutral endopeptidase (3.4.24.11) in human chronic arthritis. 214 13

The clinical, hematologic, and immunophenotypic features in 20 patients with Down's syndrome (DS) and acute leukemia were analyzed. Of the 20 patients, all 14 patients who were 3 years old and less were diagnosed as having acute megakaryoblastic leukemia (AMKL) by use of platelet-specific monoclonal antibodies and platelet peroxidase (PPO) reaction in electron microscopy. They were characterized by the presence of bone marrow fibrosis, having a history of myelodysplastic syndrome (MDS) and a poor response to chemotherapy. Only one patient has remained in continuous complete remission for more than 1 year. Acute leukemia in six patients who were older than 4 years was classified as common acute lymphoblastic leukemia antigen (CALLA)-positive acute lymphoblastic leukemia (ALL). In one of six patients classified as ALL, the leukemic blasts simultaneously expressed myeloid-associated surface antigens. All six patients achieved a complete remission and have remained in continuous complete remission and have remained in continuous complete remission from 10 to 52 months from the initial diagnosis. Although it has been suggested that the distribution of types of acute leukemia in patients with DS is similar to that in normal children, the present study shows that the distribution of acute leukemia types is quite different from that in patients without Down's syndrome.
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PMID:Down's syndrome and acute leukemia in children: an analysis of phenotype by use of monoclonal antibodies and electron microscopic platelet peroxidase reaction. 182 81

We discovered that the common acute lymphoblastic leukemia antigen, CALLA (CD10), was identical to human neutral endopeptidase 3.4.24.11 (NEP), a Zn-binding glycoprotein with an extracellular active site capable of hydrolyzing several biologically active peptides. In this study we compare the expression of CALLA/NEP in terms of antigenic density and enzymatic activity at the cell surface and of messenger RNA (mRNA) levels on granulocytes, leukemic cells, and CALLA-transfected COS-1 cells. Mature granulocytes, the only readily available source of normal human CALLA, express relatively low but constant levels of antigen, NEP activity (3.5 pmol/min/10(6) cells), and mRNA. The two major CALLA-mRNA species of 6.5 kb and 3.8 kb, observed to date in a variety of cells and tissues, were also found in four independent granulocyte preparations. With leukemia cell lines, a correlation was established between the density of CALLA antigen and the level of enzymatic activity (3.4 to 21.0 pmol/min/10(6) cells). This paper constitutes the first report of NEP activity on blast cells derived from patients with non-T acute lymphoblastic leukemia (ALL); the levels of activity were variable (1.5 to 35.9 pmol/min/10(6) cells for six cases) but correlated with the level of CALLA assessed by flow cytometry. Heterogeneous levels of expression of the CALLA-mRNA species were also observed in non-T ALL cases that correlated with the level of CALLA expression at the surface of these cells. Very high levels of NEP activity were achieved by transfecting COS-1 cells with pSV-CALLA; 20% of the transfected cells were CALLA+ and expressed 550 pmol/min/10(6) cells. Extracts prepared from COS-1 cells transfected with pSV-CALLA (carrying human NEP cDNA) and pSVENK19 (carrying rabbit NEP-cDNA), respectively, gave Michaelis constant (Km) values of 50 mumol/L and similar inhibition curves with thiorphan. Thus the recombinant proteins encoded by these two genes have similar enzymatic properties, confirming the high degree of their structural relatedness. The expression of high levels of CALLA/NEP on COS-1 cells should allow the use of this system to test the effects of specific mutations on activity and might lead to the understanding of the role of CALLA in the onset and/or progression of leukemia.
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PMID:Comparative levels of CALLA/neutral endopeptidase on normal granulocytes, leukemic cells, and transfected COS-1 cells. 216 7

A novel erythroid cell line, RM10, was established from a long-term bone marrow culture of a patient with chronic myelogenous leukemia (CML). RM10 cells were positive for periodic acid Schiff (PAS), but negative for peroxidase and dual esterase. RM10 cells had la, pre B (CD10), myeloid (CD13, CD14, CD33) and erythroid (glycophorin A) markers, but had no other lymphoid, megakaryocytic, or mesenchymal cell markers. RM10 cells spontaneously synthesized hemoglobin, which was markedly enhanced with hemin. Isoelectric focusing of the cell lysates and northern blot analysis of the total cellular RNA revealed hemoglobin synthesis in the cells. Using 125I-labeled recombinant human erythropoietin (Epo), two classes of Epo receptors were demonstrated in the RM10 cells. However, Epo did affect neither growth nor erythroid differentiation of the cells. RM10 cells rapidly differentiated to monocytic cells in the presence of 12-0-tetradecanoylphorbol-13-acetate, and simultaneously expressed glycoprotein IIb/IIIa. RM10 cells had Philadelphia chromosome (Ph), and expressed p210bcr-abl using immunoprecipitation with anti-c-abl and anti-phosphotyrosine antibodies. These results indicate that the RM10 cells have the characteristics of multipotential hemopoietic cells originating from Ph-positive CML and that high affinity Epo receptor class is not a sufficient condition for Epo responsiveness.
Leukemia 1990 May
PMID:A novel CD10-positive erythroid cell line, RM10, established from a patient with chronic myelogenous leukemia. 216 10

The presence of meningeal involvement in children with acute lymphoblastic leukemia (ALL) may have important prognostic and therapeutic implications. Conventional methods of diagnosing central nervous system (CNS) leukemia rely on the interpretation of cerebrospinal fluid (CSF) cell morphology, which may produce ambiguous results in the presence of minimal leukemic involvement. A methodology has been developed for immunophenotyping small numbers of CSF cells while preserving cell morphology. CSF samples from 33 children with CD10 (common ALL antigen [CALLA]) positive ALL were examined at initial presentation using both conventional morphology and this combined immunohistopathologic technique. Six (18%) of the samples contained lymphoblasts or cells considered morphologically suspicious for leukemic involvement. Nine additional samples (27% of the total) had normal CSF morphology, but contained increased numbers of CALLA positive cells. Twelve of the 33 samples were also examined for the simultaneous presence of nuclear terminal deoxynucleotidyl transferase (TdT) and demonstrated increased numbers of cells positive for both TdT and CD10. These data suggest that a large proportion of children with ALL may have abnormalities of CSF cells at initial diagnosis consistent with the presence of occult leukemic involvement.
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PMID:Immunophenotypic characteristics of cerebrospinal fluid cells in children with acute lymphoblastic leukemia at diagnosis. 217 1

In the present study, methotrexate (MTX), was conjugated with a murine monoclonal antibody (79) to human common acute lymphoblastic leukemia antigen (CALLA), with human serum albumin (HSA) as an intermediary. The highest molar ratio of McAb 79:HSA:MTX in the conjugates was 1:2. 63:117. The conjugates obtained retained both antibody binding and drug activities. Although there was some loss of drug activity in binding to antibody, the toxicity of McAb79-HSA-MTX was entirely specific for the target cell, and the cytotoxicity of McAb79-HSA-MTX against CALLA+ cells was greater than that of control S13 (Anti-human urokinase)-HSA-MTX. The ratio of 79-HSA-MTX cytotoxicity to the target and non-target cells was 66:1, whereas there was no cytotoxicity to target cells when McAb79 was used only. There was no cytotoxic difference between 79-HSA-MTX and S13-HSA-MTX against CALLA- SB cells. These results suggest that the cytotoxicity of 79-HSA-MTX against CALLA leukemia cells is specific and this specificity is mediated by McAb79.
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PMID:[Preparation and cytotoxicity of McAb-HSA-MTX conjugates]. 217 64

Peripheral blood mononuclear cells from 24 patients with prolymphocytic leukemia (PLL) were isolated using a Ficoll-Hypaque gradient and stained by indirect immunofluorescence using a wide panel of monoclonal antibodies against B cell restricted and associated antigens, including HLA DR (Ia), CD19, CD21 (C3dR) surface membrane immunoglobulin (Slg), CD10 (CALLA), C3b, B5, CD25 (TAC), PCA1, T9, and T10. The cells were also tested for the FMC7, defined previously on PLL cells and the RAB1, a newly described hairy cell leukemia antigen. Thirteen out of the 24 samples expressed with variable intensity all the above antigens. While Ia, CD19, CD20, FMC7, and RAB1 were strongly or moderately expressed in all, the complement receptors (CD21 and C3b) were only weakly expressed in 12 cases; and the activation antigens B5, TAC, T9, T10, and PCA1 were found with variable intensity in two-thirds of the cases. In 50% of the cases tested, the CD5 antigen (usually strongly expressed on B CLL cells) was weakly to moderately expressed. These findings (absence or weak expression of complement receptors with variable expression of activation antigens) suggest that the PLL cells are activated B cells. When stimulated in vitro by anti-mu and TPA, (phorbol ester) tumor cells showed a decrease in CD21 and Slg and a stronger expression of CD25, T9, T10, and PCA1, with evidence of Ig secretion in four out of the seven cases studied. This confirms that the PLL cells arrested at an advanced stage of differentiation progressed narrowly to more differentiated cells. In view of our findings, we believe that the term prolymphocytic leukemia is inaccurate to define the stage of cell differentiation, and we suggest calling the disease preplasmacytic leukemia.
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PMID:Further characterization of prolymphocytic leukemia cells as a tumor of activated B cells. 984 Sep 14

In the therapy studies ALL-BFM 83 and 86, immunophenotyping of ALL by monoclonal antibodies was performed in a total of 1162 protocol patients (ALL-BFM 83 n = 578; ALL-BFM 86 n = 584). Both studies yielded similar results with respect to the incidence of immunological subtypes: CD10-negative pre-pre-B ALL (ALL-BFM 83: 3.6%; ALL-BFM 86: 5.3%), common ALL (80.1%; 77.9%), B-ALL (1.9%; 2.8%), pre-T/T-ALL (13.9%; 13.5%). Leukemic cells of 3 patients in the ALL-BFM 83 study lacked lymphoid and myeloid antigens (acute unclassifiable leukemia, 0.5%), and 3 patients in the ALL-BFM 86 study exhibited different blast populations with expression of either myeloid or lymphoid features (acute mixed-lineage leukemia, 0.5%). Coexpression of myeloid antigens (CD13 and/or CD33 and/or CDw65) on lymphoblasts (My-positive ALL) was identified in 35 of the 570 (6.1%) protocol patients prospectively analyzed in the ALL-BFM 86 study. The following associations were observed between the immunological subtype and the clinical risk factors: median age (years)-pre-pre-B 3.0, common 4.3, B- 7.9, pre-T/T-ALL 8.5 (pre-pre-B, common vs. pre-T/T-ALL p = 0.05); median leukocyte counts (x 10(9)/l)-pre-pre-B 80, common 9.1, B- 12.3, pre-T/T-ALL 68.1 (common, B- vs. pre-pre-B, pre-T/T-ALL p less than 0.05). The prognostic relevance of the immunophenotype was evaluated on the basis of the therapeutic results obtained in the ALL-BFM 83 study. A significant difference in the remission rate was only recognizable between patients with common ALL (99.1%) and those with pre-T/T-ALL (93.7%, p less than 0.001). After a median follow-up of 54 months, the probability of event-free survival is 71% for pre-pre-B ALL, 67% for common ALL, 56% for pre-T/T-ALL and 27% for B-ALL (common vs. B-, pre-T/T-ALL p less than 0.001), the prognosis in patients with pre-pre-B and common ALL being markedly influenced by the initial leukocyte counts and the age.
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PMID:[Incidence, clinical markers and prognostic significance of immunologic subtypes of acute lymphoblastic leukemia (ALL) in children: experiences of the ALL-BFM 83 and 86 studies]. 220 38


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