Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.11 (CD10)
 9,792 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recombinant interferon alpha enhanced the MHC class I antigen density on human leukaemia/lymphoma cell lines REH, U-937 and HL-60, as measured by immunocytofluorometry using specific monoclonal antibodies. A similar effect was induced (as demonstrated in REH cells), also by human leukocyte interferon-alpha. The latter, however, caused no major alterations in the expression of leukocyte common antigen (ICA; CD45) and transferrin receptor (CD71) in the cell lines examined. In REH cells, there was no interferon-induced alteration of CD10 antigen (CALLA), which in this cell line is markedly down-regulated by 12-0-tetradecanoyl-phorbol-13-acetate (TPA). A decrease of CD4 antigen density on the cell membrane was induced by interferon-alpha in monoblastoid U-937 cells. No induction of MHC class I and II antigens by interferon-alpha was found in K-562 cell subline.
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PMID:Interferon alpha-induced modulation of leukocyte cell surface antigens: immunocytofluorometric study with human leukaemia/lymphoma cell lines. 168 18

A technique of simultaneous double labeling of normal and neoplastic hematopoietic cells with FITC-conjugated monoclonal antibodies directed to selectively expressed hematopoietic cell surface antigens (green fluorescence) and the anthracycline cytostatic drug (Daunomycin, red fluorescence) was described. Flow cytometric analysis of double labeled cells permitted anthracycline cell content determination in peripheral blood lymphocytes, granulocytes, monocytes from healthy donors, T- (MOLT-4), non-T, non-B (REH) and myelomonocytic (U-937) leukemic cell lines. After mixing peripheral blood lymphocytes from healthy individuals with cultured leukemic cells labeled on a restrictively expressed hematopoietic cell differentiation antigen (CALLA-CD10-, MHC class II-DR-antigen, a myelomonocytic differentiation antigen) detected by corresponding monoclonal antibodies (DGH-10-1-A9,Bra30, BraC8), the described technique allowed separate measurements of anthracycline content in leukemic cells vs. peripheral blood lymphocytes from healthy donors. Potential diagnostic aspects and research utilization of this technique are discussed.
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PMID:Fluorescent double labeling of normal and malignant hematopoietic cells by monoclonal antibodies (FITC) and anthracycline cytostatic drug (Daunomycin): a cytometric technique for analysis of drug uptake in hematopoietic cell subpopulations. 190 84

A human common acute lymphoblastic leukemia (ALL) cell line, REH, was treated in vitro with gamma-interferon (gamma-IFN) or 12-O-tetradecanoylphorbol 13-acetate (TPA). Untreated (control) and treated cells were analyzed for changes in growth patterns, morphology, cytochemistry, surface phenotype, and terminal transferase (TdT) activity. TPA but not gamma-IFN induced further maturation of REH cells along the B-cell lineage. There was a dramatic decrease in CALLA expression, loss of TdT activity, induction of Leu M5, and increase in Leu 14 expression. TPA also induced monocytoid morphological features on REH cells. Enzymatically, the induced cells strongly expressed acid phosphatase (tartrate sensitive), alpha-naphthol acetate esterase (NAE), and periodic acid Schiff (PAS). We conclude that TPA induced monocytoid B-lymphocyte features on REH cells within the B-cell lineage, which should not be confused with monocytes/macrophage. The phenotype of cells in this stage is Leu 14+, Leu M5+, BL1+, Leu 12+, AcP+, PAS+, NAE+, CALLA-, TdT-, MO1-, and MO2-.
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PMID:Induced expression of a monocytoid B lymphocyte antigen phenotype on the REH cell line. 210 37

Phorbol ester (TPA)-induced down-regulation of the common ALL (CALLA) antigen was studied by continuous flow immunocytometry with the aid of several CD10 monoclonal antibodies, including a new CD10 monoclonal antibody (DGH-10-1-A9), shown to be of IgG1 isotype, recognizing a 100 kDa cell surface protein and effectively inhibited by a series of reference CD10 monoclonal antibodies. The TPA-induced down-regulation of CALLA on REH cells was demonstrated with the aid of the following CD10 monoclonal antibodies: J-5, VIL-A1 and DGH-10-1-A9. No major modulations in cell surface expression of CALLA on REH cells were observed after induction with 1,25-(OH)2 vitamin D3, retinoic acid, recombinant interferon (IFN) alpha 2a and recombinant interleukin 2.
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PMID:Modulation of CALLA (CD10) antigen on cultured ALL (REH) cells: effect of various modulators. 214 11

The deduced amino acid sequences of CALLA, a cell surface marker of human acute lymphocytic leukemia, and human enkephalinase (neutral endopeptidase, EC 3.4.24.11) were recently reported to be almost identical. We show that membranes of CALLA+ cells of the REH lymphoblastic cell line as well as blast cells derived from the blood or bone marrow of patients with acute lymphocytic leukemia display high enkephalinase activity. This activity was abrogated by several enkephalinase inhibitors at concentrations closely similar to those required to inhibit pure human enkephalinase. However, these compounds did not significantly modify the rate of REH cell proliferation in vitro. Hence, the functional role, if any, of the high peptidase activity in lymphoblastic cells remains to be established.
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PMID:Characterisation of enkephalinase (EC 3.4.24.11) activity on various leukemic cells expressing the common acute lymphocytic leukemia antigen (CALLA). 252 3

In the present study, we established a dependable system by which human pre-B- and non-T/non-B-acute lymphoblastic leukemia (ALL) cells are efficiently transplanted into nude mice; the transplanted tumors provide a useful model for investigating the efficacy of antitumor agents in the in vivo therapy of human cancer. NALM-6 (a pre-B-ALL cell line) cells were transplanted under varying conditions as the pre-B-leukemia cells, whereas REH (a non-T/non-B-ALL cell line) cells were transplanted as the non-T/non-B-leukemia cells. Under optimal and near optimal conditions, 71 of 101 X-irradiated mice (70%) developed distinct tumors approximately 2 wk after i.d. inoculation of a mixture of NALM-6 cells and X-irradiated human fibrosarcoma cells. Under the same conditions, 9 of 11 mice (82%) developed tumors following i.d. inoculation of REH cells admixed with X-irradiated human fibrosarcoma cells. Examination of the tumor tissues demonstrated that the tumors are of leukemia origin but not of fibrosarcoma origin. To demonstrate the usefulness of the present tumors for investigating the efficacy of antitumor agents in the in vivo therapy of human cancer, immunotoxins were tested for their specific suppressive activity against growing tumors of the transplanted NALM-6 cells. To this end, monoclonal antibodies SN5 and SN6 which define a common ALL antigen, termed CALLA, and a novel leukemia-associated cell surface glycoprotein, termed gp160, respectively, were separately conjugated with the A-chain subunit of ricin, a plant toxin; CALLA and gp160 are expressed on the cell surface of various human non-T-leukemia cells including NALM-6 cells. The conjugates of SN5 and SN6 with ricin A-chain (RA) showed specific activity against the leukemia cells but not against control cells in an in vitro assay. To investigate their in vivo efficacy in suppressing tumor growth, nude mice which had been inoculated i.d. with NALM-6 cells 25 days in advance and bore distinct palpable tumors (5 to 6 mm in diameter) were divided into five groups. One group of mice was nontreated as a control. Each of the remaining four groups of mice was given an injection of one of the following agents: (a) purified control mouse IgG (IgG1); (b) purified antibodies SN5 (IgG1) and SN6 (IgG1); (c) control IgG-RA conjugate; or (d) SN5-RA and SN6-RA. Tumors in all mice of the first four groups including the untreated group grew continuously, causing the mice to die.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Efficient transplantation of human non-T-leukemia cells into nude mice and induction of complete regression of the transplanted distinct tumors by ricin A-chain conjugates of monoclonal antibodies SN5 and SN6. 296 82

Treatment of non-T/non-B human leukemic cell line REH with 5 X 10(-9) M 12-O-tetradecanoylphorbol-13-acetate (TPA) at 37 degrees resulted in their adherence to culture flasks by 24 to 36 hr and, after 72 hr, the entire surface of the flask/coverslips became covered with macrophage-like cells containing pseudopodia. Wright-Giemsa-stained untreated cells had blast morphology, whereas TPA-treated cells (adherent or excess cells remaining in suspension) had characteristic morphology of macrophages and phagocytized large numbers of latex beads. Untreated REH cells were negative for nitroblue tetrazolium reduction, Sudan Black B, and peroxidase, and they were weakly positive for periodic acid-Schiff, acid phosphatase, chloroacetate esterase (pH 6.8), and nonspecific (naphthol AS-D acetate, pH 6.8) esterase, whereas TPA-treated cells (adherent or in suspension) gave strong reaction for these stains except for peroxidase and chloroacetate esterase which showed moderate reaction. Furthermore, the nonspecific esterase activity of TPA-treated cells and weak activity in 10% of untreated cells was strongly inhibited by NaF, a characteristic of monocytic series of cells. Lysozyme activity was not detected in culture supernatant from control or TPA-treated cells. No cytoplasmic immunoglobulin was detected in untreated or TPA-treated cells, and the monocyte/granulocyte antigen (detected by MCS-2 monoclonal antibody) which was absent from untreated REH cells was expressed in TPA-treated cells. TPA-treated cells lost common acute lymphoblastic leukemia antigen but showed significantly elevated expression of histocompatibility locus DR antigen. Terminal transferase estimated by immunofluorescence and biochemical assay was high in untreated REH cells, whereas TPA-treated cells were negative in terminal transferase immunofluorescence and had only negligible terminal transferase activity in biochemical assay. All these changes in REH cells observed on TPA treatment represent the differentiation of a human leukemic non-T/non-B-cell line to macrophage-like cells for the first time which indicates that some non-T/non-B acute lymphoblastic leukemia cells may have latent monocyte-like phenotype.
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PMID:Phorbol ester-induced differentiation of a non-T/non-B human leukemic cell line (REH) to macrophage-like cells. 637

The cell-surface zinc metalloproteinase CD10/neutral endopeptidase 24.11 (CD10/NEP) hydrolyzes a variety of peptide substrates and regulates related peptide-mediated cellular responses. Because the enzyme functions as part of a peptide regulatory loop, the fact that CD10/NEP itself varies with cellular activation is of considerable interest. In hematopoietic and nonhematopoietic cell types, the levels of CD10/NEP protein and enzymatic activity correlate with transcript abundance. For these reasons, we investigated the regulation of CD10/NEP transcripts in the phorbol ester-treated acute lymphoblastic leukemia cell line, REH. When REH cells are treated with phorbol myristate acetate (PMA), CD10/NEP transcripts rapidly decrease in a labile protein-dependent manner. PMA has a modest effect on CD10/NEP transcription and significantly reduces CD10/NEP mRNA stability. Of note, the predicted secondary structure of the CD10/NEP 3' untranslated region includes several stem loop structures that may affect the stability of CD10/NEP transcripts.
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PMID:Phorbol ester-mediated regulation of CD10/neutral endopeptidase transcripts in acute lymphoblastic leukemias. 853 91

A large number of continuous human leukemia cell lines have been established over the last three decades. Clearly, leukemia cell lines have become important research tools. Here, we have summarized the immunological, molecular and standard cytogenetic features of a panel of well characterized B cell precursor (BCP)-leukemia cell lines which were derived from patients with acute lymphoblastic/undifferentiated leukemia (ALL/AUL) or chronic myeloid leukemia (CML) in blast crisis. Following the recently proposed immunological EGIL classification, we assigned our panel of 27 BCP-cell lines to one of the following categories: B-I pro-B cell line; B-II common-B cell line; and B-III pre-B cell line. All cell lines express general B-lineage associated surface markers (HLA-DR, CD22, CD79a) being negative for surface immunoglobulin (Ig); the differences between the subgroups reside in expression of CD10 and cytoplasmic Ig. Several BCP-cell lines show the myelomonocytic cell-associated markers CD13 and/or CD33. These immunologically 'biphenotypic' BCP-cell lines are generally TdT+ CD10+ CD13+ CD19+ CD22+ CD34+ and carry the Philadelphia (Ph) translocation. The BCP-cell lines display surface receptors for interferon-gamma (CD119), interleukin-7 (CD127) and FLT-3 ligand (CD135). All BCP-cell lines examined have complex numerical and structural chromosomal alterations including translocations commonly seen in BCP-ALL such as t(4;11), t(9;22), t(11;19), t(12;21), and t(17;19) involving the fusion genes MLL-AF4, BCR-ABL, ENL-MLL, TEL/ETV6-AML1 and E2A-HLF, respectively. Besides the expected rearrangement of the Ig heavy chain receptor gene, several cell lines also have rearrangements of the T cell receptor genes beta, gamma or delta. While some BCP-cell lines express (aberrantly) myeloperoxidase at the mRNA level, most lines are negative in the immunological or cytochemical staining. Several large series documented the difficulty in establishing such BCP cell lines with success rates in the range of 10-20% (on average 15%). Still, since the establishment of the first bonafide BCP-cell line in 1974 (cell line REH), some 150 cell lines have been established of which, however, only a small percentage have been sufficiently well characterized and described. A higher success rate for immortalizing any given leukemia cell might depend on a closer emulation of the physiological in vivo microenvironment. The possibility to grow in vitro leukemia cells at will would represent ideal experimental systems permitting basic research and patient-specific investigations. In summary, the use of well-characterized BCP-cell lines provide unprecedented opportunities for studying a multitude of biological aspects related to normal and neoplastic B-lymphocytes.
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PMID:Establishment and characterization of human B cell precursor-leukemia cell lines. 968 Jan 6

In an attempt to identify differentiation-related changes in cellular proteins, the common acute lymphoblastic leukemia (ALL) cell line, REH, was studied. REH cells were cultured in either the absence or presence of 12-0-tetradecanoylphorbol-13-acetate (TPA). Changes in surface phenotype were analyzed using monoclonal antibodies and flow cytometry. Cellular proteins were analyzed with two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) of [(3)H]leucine and [(32)P]orthophosphate labeled cells. Immunophenotype and 2D-PAGE studies were replicated three times on untreated (control) and TPA-treated cells on day 5. Immunophenotypic analysis showed that TPA induced further differentiation of REH cells along the B-cell lineage as indicated by significant decrease in the expression of CD10, induction of CD11c and increase in the expression of CD22. 2D-PAGE of [(3)H]leucine but not the [(32)P]orthophosphate showed that TPA induced the expression of a unique protein. The apparent relative molecular mass (Mr) of the resolved protein was ~23 kd with a ~6.2 isoelectric point (PI). Based on the morphologic and phenotypic findings, our data suggest that the new protein (p23-6.2) and the quantitative changes in protein synthesis induced by TPA are differentiation-related. Our study also indicates that 2D-PAGE analysis is a sensitive and complementary tool to phenotypic markers in the study of differentiation of malignant B-cells.
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PMID:Expression of a New Cellular Protein by Monocytoid B-Lymphocytes Differentiated from the Acute Lymphoblastic Leukemia Cell Line (REH). 2746 48


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