Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Copper-67 (67Cu) is one of the most promising radiometals for radioimmunotherapy because of its 61.5 hr physical half-life, abundant beta particles, and gamma emissions suitable for imaging. However, 67Cu is readily transferred from the usual chelates of EDTA or DTPA to albumen. We developed a new macrocycle (6-p-nitrobenzyl-TETA) to chelate copper. Bifunctional chelating agent p-bromoacetamidobenzyl-TETA was conjugated to Lym-1, a monoclonal antibody against human B cell lymphoma, without significantly altering its immunoreactivity. This conjugate was stably labeled with 67Cu under conditions chosen to optimize the yield of a high specific activity radiopharmaceutical. The biodistribution in RAJI tumor bearing mice demonstrated significant tumor uptake (14.7% ID per gram) and extended residence time (120 hr) in contrast to normal organs. After 24 hr, radioactivity was continuously cleared from all tissues except the tumor. This study suggests 67Cu labeled Lym-1 to be a promising radiopharmaceutical for potential use for radioimmunotherapy of B cell lymphoma.
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PMID:Copper-67-labeled monoclonal antibody Lym-1, a potential radiopharmaceutical for cancer therapy: labeling and biodistribution in RAJI tumored mice. 325 25

The mechanism by which 7,12-dimethylbenz[a]anthracene (DMBA) produces cytotoxicity in lymphocytes was investigated in these studies using the murine A20.1 B cell lymphoma. Results show that in vitro exposure of these cells to 10-30 microM DMBA for 4 hr produced an increase in intracellular Ca2+, DNA fragmentation, and subsequent cell death. Elevation of Ca2+ and DNA fragmentation induced by DMBA were greatly pronounced when the A20.1 cells were exposed at high cell density (10(7) cells/ml). DMBA-induced DNA fragmentation and cell death were inhibited by coexposure of A20.1 cells to a calcium chelator (EDTA), a general nuclease and polymerase inhibitor (aurintricarboxylic acid), and a protein synthesis inhibitor (cycloheximide). These agents have been previously shown to inhibit apoptosis in lymphocytes and other cells exposed to chemical agents. We also found that cyclosporin A, an inhibitor of Ca(2+)-dependent pathways of T and B cell activation, prevented apoptosis in the A20.1 cell line. These results demonstrate that DMBA induces programmed cell death (apoptosis) in the A20.1 murine B cell lymphoma by Ca(2+)-dependent pathways. The increased sensitivity of A20.1 at high cell density to Ca2+ elevation and DNA fragmentation suggests that cell to cell interactions may also be important in this process.
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PMID:DMBA induces programmed cell death (apoptosis) in the A20.1 murine B cell lymphoma. 836 79

The CD53 antigen is a member of the tetraspan family of proteins with unknown function. Stimulation of rat IR938F B-cell lymphoma cells with monoclonal antibody MRC OX44 (anti-rat CD53) triggered a homotypic adhesion reaction which reached a maximum effect at 24 hr. This effect occurred at 37 degrees C but not at 4 degrees C. Adhesion was prevented by removal of divalent cations, Ca2+ and Mg2+, with EGTA and EDTA as chelating agents. The adhesion induced by MRC OX44 was inhibited by cycloheximide and actinomycin D, suggesting that de novo protein synthesis was required for this effect. The addition of mAb WT1 against rat LFA-1 (CD11a) antigen had no effect on adhesion, suggesting that the cell-cell interaction is not mediated by the expression of LFA-1 antigen. The intracellular signals required to induce adhesion were inhibited by two tyrosine kinase inhibitors, genistein and piceatannol. Wortmannin, a selective inhibitor of phosphoinositide 3-kinase activity, completely blocked adhesion. Two protein kinase C inhibitors, H7 and bisindolylmaleimide, inhibited the adhesion, suggesting that part of the signal is mediated by PKC. Electron microscopy of aggregated cells showed that the interaction is localized to short membrane regions, where contact areas of higher density in opposing zones from both cells were detected. We postulate that there is a common adhesion mechanism that is modulated by several tetraspan family members and associated proteins. This adhesion structure might represent a novel form of cell communication among lymphoid cells.
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PMID:Ligation of CD53/OX44, a tetraspan antigen, induces homotypic adhesion mediated by specific cell-cell interactions. 922 4

A 48-year-old man, with persistent pyrexia, presented with thrombocytopenia and lymphocytosis. The peripheral blood smears showed atypical lymphocytes and a platelet satellitism phenomenon around atypical lymphocytes associated to lympho-agglutination. Platelet satellitism was exclusively observed with atypical lymphocytes in EDTA-treated blood and at room temperature. This phenomenon was not observed when adding normal plasma and could be reproduced several times. Flow cytometry analysis of the peripheral blood, cytological and histological studies revealed a marginal zone-B cell lymphoma. The mechanism underlying platelet satellitism is not fully understood, but is likely to involve an immunologic binding of EDTA-dependent antiplatelet autoantibodies directed against the platelets glycoprotein IIb/IIIa complex. The association between platelet satellitism and lymphoma could also involve a monoclonal Ig secreted by lymphoma cells.
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PMID:[A marginal zone-B cell lymphoma revealed by platelet satellitism and lympho-agglutination phenomenon around atypical lymphocytes]. 1750 2