Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary IgM antibody responses to synthetic linear copolymers of L-glutamic acid, L-tyrosine, and L-alanine were investigated. The appearance of primary IgM anti-GAT antibodies was detected in BALB/c mice by using a solid phase radioimmunoassay (SPRIA) procedure. The finding was verified for GAT in responder mice and GAT-MBSA and GT-MBSA in nonresponder mice in an indirect plaque forming cell (PFC) assay by using a rabbit antiserum directed against the mulambda myeloma protein, MOPC 104E. Facilitated IgM PFC could be inhibited by a purified muK myeloma protein, TEPC 183. Maximal facilitated IgM plaque response was found to precede the IgG response by several days. A direct plaque assay was developed for the detection of IgM anti-GAT plaques using poly-L-lysine (PLL) to couple GAT to sheep erythrocytes (SRBC). GAT-SRBC coupled by the PLL method optimally couple 4 to 5 times less antigen to the indicator cell surface than does the CrCl3-coupling method routinely employed in our laboratory. These findings were extended to a conventional antigen, chicken gamma globulin (CgammaG). We found that a less dense epitope coat on the indicator cell surface favors detection of direct IgM PFC, whereas a more densely coated indicator cell favors the detection of facilitated IgM and IgG PFC responses.
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PMID:Characterization of the primary IgM response to GAT and GT: conditions required for the detection of IgM antibodies. 8 20

It is well documented that despite global abnormalities of the immune system in AIDS and other immune deficiency diseases or in immunosuppressed patients, the incidence of only a few kinds of tumor increases, and that the degree of immunosuppression seems not to be a critical factor in the development of even these tumors. The fact that tumors do not develop in the majority of population during their lifetime, despite the ineffectiveness of the known immune system against the majority of tumors, can only be explained by hypothesizing that the living system has an additional defense mechanism against tumors. On the bases of literary data, it can be assumed that the effective agents of this defense mechanism are certain substances of the circulatory system. We proved this hypothesis by being able to select thirteen substances of the circulatory system from 71 compounds tested, using the synergistic tumor cell-killing effect as criteria. The mixture containing the thirteen substances (L-tryptophan, L-tyrosine, L-methionine, L(-)-malate, L-ascorbate, L-arginine, L-phenylalanine, L-histidine, 2-deoxy-D-ribose, d-biotin, pyridoxine, adenine and riboflavin) had a cytotoxic effect against Sp2/0-Ag14 mouse and K562, HEp-2, HeLa and Caco-2 human tumor cell lines in well-controlled conditions, but it was not cytotoxic against Vero normal cell line. The mixture of the above substances increased significantly the survival time of mice (T/C% 148.1) injected i.p. with Sp2/0-Ag14 mouse myeloma cells by killing more than 2 logs (99%) of the cells. Approximately the same 2 logs cell kill was found counting the Sp2/0-Ag14 cells in the ascitic fluid of control and treated animals after finishing treatment. The above mixture slowed down the growth of HeLa solid tumor significantly (T/C%, the least value 35.7). The weight loss of control and treated group during treatment did not differ significantly.
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PMID:Inhibition of the growth of a murine and various human tumor cell lines in culture and in mice by mixture of certain substances of the circulatory system. 766 76

The aim of this study was to investigate the cellular uptake mechanisms responsible for the accumulation of 3-[(125)I]iodo-L-alpha-methyltyrosine ((125)I-3-IMT) and 2-[(125)I]iodo-L-tyrosine ((125)I-2-IT), two radiotracers for metabolic tumor imaging, using single-photon emission tomography, into U266 human myeloma cancer cells. Time course and concentration dependency of (125)I-3-IMT uptake was assessed. Kinetic parameters were calculated using an Eadie Hofstee plot. A set of competitive inhibitors of the main amino acid transport systems was used for the discrimination of the transporters responsible for the uptake of (125)I-3-IMT and (125)I-2-IT. Protein incorporation of both tracers was determined using acid precipitation. The measured maximum velocity for (125)I-3-IMT transport was 4.199 nmol per mg protein 20 s(-1), and the Michaelis constant was 107.9 microM. Addition of 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid (BCH), a competitive inhibitor of System L, reduced the influx by 39.0+/-3.3% for (125)I-3-IMT and 66.3+/-0.9% for (125)I-2-IT. The BCH-insensitive influx was further reduced by Tryptophan (Trp) by 43.8+/-3.5% for (125)I-3-IMT and 15.3+/-1.3% for (125)I-2-IT. This suggests involvement of System T transport. We measured <2% of radioactivity in the acid precipitable fractions of both tracers with no increase in time. We conclude that the influx of (125)I-3-IMT and (125)I-2-IT into U266 human myeloma cells is mediated by both System L and System T amino acid transporters. The kinetic parameters suggest that elevated plasma levels of aromatic amino acids will reduce (123)I-3-IMT uptake in myeloma patients. Both tracers do not enter protein synthesis significantly.
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PMID:In vitro characterization of the influx of 3-[125I]iodo-L-alpha-methyltyrosine and 2-[125I]iodo-L-tyrosine into U266 human myeloma cells: evidence for system T transport. 1129 23