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)

The A-chains of ricin obtained from Ricinus communis or mistletoe lectin I from Viscum album were coupled to the monoclonal, anti-L1210V antibody MoAb-16, using SPDP as a cross linking agent. The cytotoxic activity in vitro of these immunotoxins was compared. Each of two immunotoxins tested, applied in vitro for 1 h in appropriate doses, caused irreversible inhibition of leukemic L1210 cells proliferation. Unexpectedly, MoAb-16-MLIA immunotoxin appeared to be cytotoxic to normal bone marrow progenitor cells, as observed in NCFUS tests. Moreover, this immunotoxin revealed cytotoxic effect to the P388 leukemia cells which do not share the antigen, common within L1210 leukemia cells, detected by MoAb-16 antibody.
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PMID:The activity of two immunotoxins composed of monoclonal antibody MoAb-16 and A-chain of ricin (MoAb-16-RTA) or A-chain of mistletoe lectin I (MoAb-16-MLIA). 130 Sep 87

We have previously shown that leukemia/lymphoma (LL) cells adhere to marrow stromal cells (MSC), and MSC induce clonal growth of LL cells. Even though CD11a/18 and CD54 are important in leukocyte and endothelial cell interaction, the literature suggested that these adhesion proteins are not involved in adhesion of hematopoietic stem cells to MSC. We therefore utilized a unique ICAM-1- murine MSC line (MLT) to evaluate the mechanisms of adherence of LL cells (L5178Y and L1210) to MLT. Adherence of LL cells to extracellular matrix (ECM) proteins was also examined. L1210 cells attached to collagen types III and IV, laminin, and fibronectin, but not to collagen type I. L5178Y cells did not attach to any of the ECM proteins tested. The adherence of both L1210 and L5178Y to MSC was unaffected by rat monoclonal antibodies to murine CD11a, CD11b, and CD18. Neoglycoprotein probes, mannosyl-bovine serum albumin (BSA) and galactosyl-BSA, inhibited the adherence of L5178Y and L1210 cells to MSC by 34%-63% of controls at concentrations of 10(-3) and 5 x 10(-3) M. In contrast, fucosyl-BSA had no inhibitory effect on LL cell adherence of MLT. These data suggest that 1) LL cells may adhere to MSC by a lectin mechanism with mannosyl and galactosyl specificities; and 2) other mechanisms of adherence, not yet defined, are also important in this system.
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PMID:Heterotypic adherence between murine leukemia/lymphoma cells and marrow stromal cells involves a recognition mechanism with galactosyl and mannosyl specificities. 134 82

Lymphocytes leave the blood via post-capillary venules by binding initially to their specialized endothelium. CD44 is a 80-90 kDa hyaluronate-binding glycoprotein involved in binding to endothelium of high endothelial venules (HEV). LECAM-1 is a 75-85 kDa glycoprotein with lectin activity interacting with human peripheral lymph node vascular addressin (PNAd) on HEV. This immunohistochemical study shows that CD44 and LECAM-1 are essentially coordinately expressed on B-lymphocytes. The mode and level of CD44/LECAM-1 expression dissect the peripheral B-cell development into stages that are closely linked to morphologically defined B-cell compartments. Although statistically correlated in B-cell leukaemias (p < 0.0009) and extranodal B-cell lymphomas (p < 0.003), expression of both molecules was less stringently coordinated in 127 B-cell neoplasms examined. B-cell chronic lymphocytic leukaemia, hairy cell leukaemia and mantle zone lymphoma were CD44/LECAM-1 positive, thus corresponding to their reactive counterparts. Correspondingly, follicular centre cell-derived lymphomas were devoid of both markers. Conversely, CD44 and LEC-AM-1 were infrequently detectable in extranodal malignant B-cell neoplasms, irrespective of their maturational state. Presence versus absence of CD44 and LECAM-1, alone or together, determined neither the leukaemic versus aleukaemic state nor the nodal versus extranodal tumour-forming phenotype of a B-cell tumour.
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PMID:Venular endothelium binding molecules CD44 and LECAM-1 in normal and malignant B-cell populations. A comparative study. 138 25

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

The lectin peanut agglutinin (PNA) was used to study the surface carbohydrate expression of galactose beta 1, 3, N-acetylgalactosamine by normal and malignant hemopoietic cells. Immunostaining was performed using biotinylated PNA and a streptavidin-alkaline phosphatase staining technique on 78 patients. The study was undertaken to enlarge on previous reports of lectin binding to cells of hemopoietic origin and to establish the potential role of biotinylated PNA as a component of an immunotoxin for in vitro purging of bone marrow in patients with multiple myeloma. In normals only monocytes, macrophages, centroblasts and plasma cells showed reactivity. Of the hematological malignancies, all cases of multiple myeloma were positive and non-Hodgkin's lymphoma cases with a large cell component had positive centroblasts. Two of 5 cases of acute myelomonocytic leukemia, one case of chronic myelomonocytic leukemia and one case of pleomorphic T cell non-Hodgkin's lymphoma showed PNA positive neoplastic cells. The reactivity of biotinylated PNA with centroblasts and plasma cells suggests that it may be of potential value when linked to a streptavidin-ricin conjugate in the in vitro purging of bone marrow of patients with multiple myeloma prior to autologous bone marrow transplantation.
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PMID:Peanut agglutinin (lectin from Arachis hypogaea) binding to hemopoietic cells: an immunophenotypic study using a biotin streptavidin technique. 143 89

Forty patients with different varieties of leukaemia and lymphoma were studied before and after therapy. Red cells and lymphocytes from each patient were tested for foetal antigen by lectin-agglutination test. The antigen was detectable on red cells in all untreated cases, the highest titre being found in chronic myeloid leukaemia. The titre showed significant reduction after treatment in all cases. We conclude that foetal antigen on red cells is a useful diagnostic aid in haematological malignancy and is a good indicator of the outcome of therapy.
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PMID:Study of foetal antigen in haematological malignancy. 145 63

In order to clarify the cellular tropism of human T-cell leukemia virus type I (HTLV-I) and the effects of HTLV-I infection on T-cell functions, we investigated the infectiousness of HTLV-I on T cells bearing T-cell receptor (TCR) gamma delta and functional alterations of the HTLV-I-infected TCR-gamma delta + T cells. CD3+ CD4-CD8-TCR-gamma delta + T-cell clones which possessed cytotoxicity were co-cultured with a HTLV-I-producing T-cell line. After several weeks, integration of HTLV-I proviral DNA in TCR-gamma delta + T cells was detected by Southern blot analysis. During the continuous culture of HTLV-I-infected TCR-gamma delta + T-cell clones, 2 distinct phases were observed in terms of cytotoxic activity and expression of the CD3-TCR-gamma delta complex. Early after HTLV-I infection, TCR-gamma delta + T cells lost their spontaneous cytotoxicity, but this was restored by the addition of lectin. At this time, no differences were observed in the expression of various surface molecules between HTLV-I-infected and uninfected parent cells, except for increased expression of CD25 on HTLV-I-infected cells. At about 30 weeks after HTLV-I infection, the cytotoxicity of HTLV-I-infected cells was almost completely lost, even in the presence of lectin, and expression of the CD3-TCR-gamma delta complex on the cell surface was markedly decreased. Concomitant with the decreased expression of CD3-TCR-gamma delta complexes, a decrease in the elevation of cytoplasmic Ca2+ concentration induced by anti-CD3 and anti-TCR monoclonal antibodies (MAbs) was also observed. Our present findings thus show that HTLV-I can infect TCR-gamma delta + T cells, and that consequently their functions are profoundly affected through 2 distinct phases.
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PMID:Human T-cell leukemia virus type I(HTLV-I) infection of T cells bearing T-cell receptor gamma delta: effects of HTLV-I infection on cytotoxicity. 153 Dec 9

Using a preembedding electron microscopic technique, the binding and internalization of gold labelled mistletoe lectin I (MLI.Au), its 2 A subunits (MLI-A.Au) and of the B subunit (MLI-B.Au) in murine L 1210V leukemia cells was analysed. Furthermore, the endocytosis of a gold marked immunotoxin (MoAb-16-MLI-A.Au), consisting of a monoclonal antibody (MoAb-16) reacting with L 1210V cells and the cytotoxic A subunits (MLI-A) was detected. The cells were incubated with MLI.Au, MLI-A.Au, MLI-B.Au, or MoAb-16-MLI-A.Au at 37 degrees C for 1, 3, 5, 10, 20 or 30 min, respectively. Remarkable differences were found in the endocytotic pathway and internalization kinetics. The endocytosis of MLI, its subunits and of the immunotoxin has been compared to that of the other ligands in various systems.
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PMID:Comparative studies on internalization of gold labelled mistletoe lectin I (MLI), its subunits, and of an immunotoxin into mouse L 1210V leukemia cells. 158 Jan 41

Activation of resting human peripheral blood T lymphocytes by the lectin phytohemagglutinin results in an increase in methionine adenosyltransferase (MAT) activity, accompanied by an increase in the amount of the alpha/alpha' catalytic subunits of the enzyme. In contrast, the amount of the noncatalytic beta subunit remains constant throughout the course of the response. Using both polyclonal antibodies to the holoenzyme and monoclonal antibodies to the alpha/alpha' subunits, we detected a cross-reactive 68-kDa protein, which we refer to as lambda. This protein is present in high abundance in resting T cells but decreases upon cell stimulation, as both MAT activity and the amount of the catalytic alpha/alpha' subunits increase. The decrease in lambda and increase in alpha/alpha' occurs after interleukin-2 production and before DNA synthesis. lambda virtually disappears when the cells are actively dividing. Several continuous T cell lines (HPB-ALL, MOLT-4, and Jurkat) as well as a freshly isolated T cell leukemia (ALL-2) had no detectable lambda. The Km for L-methionine for enzyme from resting peripheral blood mononuclear cells was 19-23 microM, which is 3-8-fold higher than purified MAT from fresh leukemic cells or enzyme from Jurkat cells, both of which have a Km of 3.5-3.8 microM. Kinetic analysis of enzyme activity from activated peripheral blood mononuclear cells suggested the presence of two forms of enzyme catalyzing the synthesis of AdoMet. After separation of lambda from the alpha and beta subunits by hydrophobic chromatography, it was determined that lambda has MAT activity but that it is significantly less active than the form containing the alpha subunit. It therefore appears that in resting T cells MAT is sequestered as a less active form. We hypothesize that lambda is a precursor to the catalytic subunits of human lymphocyte MAT and propose that the transition from lambda to alpha/alpha' may be important in the response of T cells to mitogenic signals.
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PMID:Changes in the relative amount of subunits of methionine adenosyltransferase in human lymphocytes upon stimulation with a polyclonal T cell mitogen. 158 46

The authors describe a method for the detection of carbohydrate determinants contained by the cellular surface membrane glycosylated biopolymers, based on the use of horse radish peroxidase-conjugated Arachis, Helix pomatia, Ricinus communis, Lens, Glycine max, Sophora japonica lectins. The pattern of lectin receptor distribution on normal human blood lymphocytes, tonsillar lymphoid cells, and in some forms of leukemia and lymphoma is shown. The authors consider it essential that a lectin kit be used along with enzymochemical and immunocytochemical markers as an additional test for the diagnosis of various forms and types of malignant lymphoproliferative diseases.
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PMID:[Determination of lectin receptors on the surface membranes of lymphoid cells]. 169 58


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