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

A brief review of the origin and tumor-inducing properties of Abelson murine leukemia virus is given. The most common neoplasm induced by this virus in vivo is a nonthymic lymphocytic tumor of bone marrow and lymph node origin. Two morphologic types of lymphosarcomas are the undifferentiated lymphosarcoma (LS) and the plasmacytic lymphosarcoma (PL). With the electron microscope, both tumor cell types may be mixed and contain undifferentiated cells or cells with a moderate amount of rough endoplasmic reticulum and polysomes. PL tumors are composed predominantly of the latter. In biosynthetic studies, PL tumors produce more immunoglobulin (Ig) than LS and more of the Ig-heavy chain, which is thought to be the murine counterpart of IgD. PL-cells sensitized with rabbit antisera to mouse kappa chains formed rosettes with formalinized protein-A producing Staphylococcus aureus Cowan I strain. The rabbit antisera were specific for kappa chains by absorption. The failure of lymphosarcoma cells to secrete Ig indicates their differentiation is blocked by the transformation process. Lymphosarcoma cells appear then to be derived from B-lymphocytes.
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PMID:Immunoglobulin production by lymphosarcomas induced by Abelson virus in mice. 21 59

Immunochemical studies of murine thymus-leukemia antigens (TLA) have confirmed that the subunit structure consists of a 45,000-dalton heavy chain and a beta 2 microglobulin (beta 2m) light chain. Similar structural features are exhibited by the TLA from thymocytes of Tlaa, Tlac, Tlad, and a leukemia cell derived from C57BL/6, a Tlab strain. In addition to the similar subunit structure from the four haplotypes, each TLA shows a similar pattern of trypsin proteolysis. This procedure yields a major heavy chain cleavage product of approximately 37,000 daltons that remains associated with beta 2m and retains most or all of the antigenic determinants of the intact TLA. Evidence is presented that TLA do not exhibit Fc receptor properties, nor do they adsorb to murine leukemia virus antigens under the conditions of isolation for analysis on polyacrylamide gel electrophoresis (PAGE) in sodium dodecyl sulfate (SDS). Taken together these findings strongly support the hypothesis that TLA comprise a family of chemically similar antigens belonging to a structurally and genetically related group that includes H-2D, H-2K, and Qa-2,3.
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PMID:Shared chemical properties of different murine thymus-leukemia antigens. 44 10

The effect of the activity present in the globulin fraction of the serum of patients with acute leukaemias and thrombocytopenia on the isologous platelets was investigated. This activity caused, due to increased availability of platelet factor 3, an acceleration of the endogenous clotting pathway with resulting shortening of the clotting time in the test of platelet factor 3 availability. This test was done in 44 patients with acute leukaemia and 19 with thrombocytopenia demonstrating a high-grade shortening of the clotting time as compared with that in a group of 30 healthy controls. In some cases of complete remission of acute leukaemia an effect of this activity on the autologous platelets was demonstrated. The antiplatelet activity was inhibited by rabbit serum against human IgG and Fc fragment of the heavy chain in IgG. These results suggest that the activity present in the globulin fraction of the serum may be one of the causes of thrombocytopenia in acute leukaemia.
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PMID:[Blood serum antiplatelet activity in acute leukemia and idiopathic thrombopenia studied with the aid of the platelet factor 3 availability test]. 53 51

Immunoglobulins were detected on the membranes of human leukemic cells by a microcytotoxicity technique. A significant percentage of lymphocytes from normal donors failed to react with goat antisera to human heavy chain determinants or to lambda-light chains. Lymphocytes from some normal donors, however, did react with antisera to k-light chains. A high percentage (50-90) of cells from some leukemia patients were killed by antisera to light chains and by one or more antisera to heavy chain determinants. Trypsin treatment of leukemic cells resulted in a loss of cytotoxic activity with all immunoglobulin antisera. Reactivity with the k-light chain antiserum was detectable 2 h after trypsinization of chronic myeloid leukemic (CML) cells and 8 h after treatment of acute lymphocytic leukemic (ALL) cells. Reactivity with the antisera to heavy chain determinants and lambda-light chains could not be detected 8 and 48 h after trypsinization of CML and ALL cells, respectively. The cytotoxic activity of the immunoglobulin antisera to heavy chains was abolished by absorption with the specific immunoglobulin used to define the antisera by precipitation. Eluates (pH 3.2) prepared from leukemic cells which reacted by cytotoxicity with the immunoglobulin antisera were shown to contain immunoglobulins of different heavy chain classes. In addition, some of the eluates had cytotoxic antibody activity to human leukemia cells. The specificity of the eluted antibodies is similar to the specificity previously described for cytophilic antibodies from leukemic patients and nonhuman primate antisera to human leukemia cells. The possible in vitro detection and in vivo significance of the eluted non-complement-fixing antibodies is considered.
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PMID:Membrane-bound immunoglobulins on human leukemic cells. Evidence for humoral immune responses of patients to leukemia-associated antigens. 80 98

The surface of lymphocytes obtained from fresh biopsy specimens from 41 patients with malignant lymphoma and from 30 normal subjects or patients with non-neoplastic lymphadenopathy were investigated. Immunoglobulin on the cell surface was used to identify B cells, whereas T cells were recognized by their reactivity with an antithymocyte antiserum and their ability to form rosettes with sheep erythrocytes. Normal and inflammatory lymph nodes were composed predominantly of T lymphocytes, as were nodes from 14 patients with Hodgkin's disease. Two thymomas were T cell proliferations, whereas a node from a patient with ataxia-telangiectasia was devoid of T lymphocytes. The presence of immunoglobulin on the cell surface indicated that 19 of 21 lymphocytic lymphomas were B cell proliferations, whereas the cells from 3 histiocytic lymphomas (reticulum cell sarcomas) and 1 mixed histiocytic and lymphocytic lymphoma were devoid of surface immunoglobulin. In immunoglobulin-positive tumors, one predominant heavy chain and one predominant light chain could usually be identified, thus establishing the clonal character of the neoplastic proliferation. Ten of 11 diffuse poorly differentiated lymphocytic lymphomas were composed of cells with large amounts of surface immunoglobulin, whereas only 1 of 5 diffuse well differentiated lymphocytic tumors contained such abundant surface immunoglobulin. The surface immunoglobulin data indicate the existence of at least two subspecies of B cell neoplasms. A small lymphocyte with sparse surface immunoglobulin proliferates as diffuse well differentiated lymphocytic lymphoma and chronic lymphocytic leukemia, whereas a larger lymphocyte with abundant surface immunoglobulin proliferates as diffuse poorly differentiated lymphocytic lymphoma and lymphosarcoma cell leukemia.
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PMID:Lymphocyte surface characteristics in malignant lymphoma. 109 Jan 57

Blast cells from a female patient with acute lymphoblastic leukemia-hand mirror variant were examined using various techniques, including light and ultrastructural morphologic examination, cytochemical analysis, surface antigen characterization, cytogenetic analysis, and gene rearrangement studies. The blast cells were found to be pre-B cells (CD19+ and Tdt+) that also expressed the myeloid antigens CD13 and CD33 and demonstrated a heavy chain immunoglobulin gene rearrangement. Cytogenetic studies revealed a t(11;19) translocation previously described in biphenotypic leukemias. A subset of acute lymphoblastic leukemia-hand mirror cells has been previously defined and includes predominately female patients with an indolent course. The authors' findings place this case, a mixed leukemia, within that subgroup. The possibility of mixed lineage should be considered in future cases of hand mirror variants of adult acute lymphoblastic leukemia. Furthermore, hand mirror morphologic features in any case of acute leukemia should alert the hematopathologist/hematologist to the possibility of mixed lineage.
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PMID:Hand mirror variant of adult acute lymphoblastic leukemia. Evidence for a mixed leukemia. 128 57

Acute lymphoblastic leukaemia (ALL) of infants aged less than 1 year represents a group of patients with peculiar biological features, poor response to therapy and unfavourable prognosis. In order better to characterize this type of leukaemia, we have investigated the immunoglobulin (Ig) and T-cell receptor (TCR) genes configuration of 21 infants with ALL, and compared the genotypic features with the phenotypic and karyotypic data, as well as with the clinical outcome. All cases had a pre-B phenotype; 12 (57%) of them were pre-pre-B ALL (CD10-, CD19+). Six of the 16 cases evaluated (38%) displayed chromosomal abnormalities; five had the typical translocation t(4;11)(q21;23). Eleven cases presented with a white blood cell count greater than 100 x 10(9)/l. The clinical course was unfavourable in 14 patients. The genotype of this group of ALL revealed several peculiarities. (1) Of the 21 cases, six (29%) displayed a multiple rearrangement pattern at the IgH locus. (2) In three cases (15%), the light chain genes were rearranged. (3) The TCR beta and gamma genes were rearranged in only one case (one case at the TCR beta and one at the TCR gamma locus). (4) The TCR delta chain was rearranged in eight cases (40%) and rarely deleted; the rearrangements observed were those most frequently observed in B cell-precursor ALL. Two cases were evaluated both at presentation and at relapse. While the immunophenotype had remained unmodified, comparison of Ig heavy chain gene rearrangements revealed clonal variations in both cases. Taken together, these findings further underline the biological peculiarities of infant ALL compared to ALL which occurs in older children and in adults, and stress the need of differentiated and aggressive therapeutic approach for these patients.
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PMID:Unique genotypic features of infant acute lymphoblastic leukaemia at presentation and at relapse. 131 41

Epstein-Barr-virus- (EBV-) positive lymphoblastoid cell lines (LCLs) spontaneously arising in vitro were obtained from the peripheral blood of six HIV-seropositive patients and from the peripheral blood and the bone marrow of one patient (LAM) with AIDS and lymphoma. The LCLs from HIV-seropositive patients had phenotypic, cytogenetic, and biological characteristics indistinguishable from those of normal LCLs obtained by infecting B cells with EBV in vitro. The LCLs from LAM patient comprised composite cell populations. Cloning analysis and cell fractionation procedures showed that, beside normal EBV-infected cells, these lines contained a malignant subset population characterized by c-myc rearrangement, abnormal karyotype, and a surface phenotype similar to that of Burkitt's lymphoma cells. Analyses of Ig heavy chain and c-myc oncogene loci showed that these malignant cells were the progeny of a single precursor. Nevertheless, these cells had heterogeneous EBV-fused termini, a finding which indicates that EBV infection followed c-myc rearrangement.
Leukemia 1992
PMID:Characterization of EBV-positive lymphoblastoid cell lines obtained from HIV seropositive patients with or without lymphomas. 131 63

To identify the cellular receptors and other cell surface molecules playing essential roles in the transmission of human T-cell leukemia virus type 1 (HTLV-1), we have been isolating monoclonal antibodies (mAbs) that are capable of inhibiting HTLV-1-induced syncytium formation. In the present study, we isolated two mAbs, H11 (IgM) and H14 (IgG1), inhibitory to syncytium formation in the coculture of TOM-1 or C91/PL (both HTLV-1-positive human T-cell lines) and MOLT-4/8 (HTLV-1-negative human T-cell line) by immunizing the membrane fraction of human osteosarcoma line HOS. By immunoprecipitation and immunoblotting, H11 and H14 were found to be specific for MHC class I heavy chain and beta 2-microglobulin (beta 2 M), respectively. Among the four commercially obtained mAbs, two mAbs for MHC class I antigen and two mAbs to beta 2 M, one mAb to MHC class I antigen and one mAb to beta 2 M were also found to be inhibitory to the syncytium formation. The functional comparison of these mAbs revealed that the syncytium-inhibitory mAbs induced strong homotypic cell adhesion particularly in the HTLV-1-positive T-cell lines. This cell adhesion was dependent on temperature, energy metabolism, and microfilament function but not on the activity of protein kinase C or divalent cations. These results suggest a novel type of LFA-1-independent cell adhesion induced by signal transduction via MHC class I antigen.
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PMID:Induction of strong homotypic adhesion in human T cell lines positive with human T-cell leukemia virus type 1 by monoclonal antibodies to MHC class I and beta 2-microglobulin. 138 Aug 95

Surface immunoglobulin on mouse B cells is associated with a heterodimer comprising the products of the mb-1 and B29 genes. Here we report that antibodies raised against a peptide sequence from the intracytoplasmic C terminus of the B29 murine gene product detect the 37-kDa component of the human heterodimer, indicating that this component in man is also encoded by the B29 gene. The immunocytochemical reactivity of these anti-B29 antibodies was compared with those of antibodies to the mb-1 protein. Of 25 cases of acute lymphoblastic leukaemia (ALL), 24 were positive for mb-1 whereas B29 was expressed in only 13 cases. Most of these B29-positive ALL expressed immunoglobulin mu heavy chain in their cytoplasm (pre-B ALL). In lymphoid tissue sections, anti-B29-labeled B cell follicles in a similar fashion to anti-mb-1, with the striking exception that plasma cells were unreactive for B29, but positive for mb-1. These results suggest that the synthesis of B29 begins later in precursor B cells than that of mb-1, and ceases before the terminal plasmacyte phase.
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PMID:The B29 and mb-1 polypeptides are differentially expressed during human B cell differentiation. 139 79


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