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)

Two peptides, P123 and P124, representing amino acid sequences His 542-Lys 557 and Tyr 459-Arg 472, respectively, of the CH4 domain of rat IgE and predicted to be located on accessible regions of the protein were synthesized by a solid-phase procedure. Rabbits were immunized with the peptides conjugated to KLH and their antisera were tested for reactivity with free peptide and rat IgE by inhibition-ELISA. Each animal produced antibodies which reacted specifically with its immunizing peptide (titre greater than 1/62,500), but not with other synthetic peptides of similar chain-length and composition. Antisera directed against peptides P123 and P124 specifically bound purified rat IgE (IR 162) and IgE in whole myeloma serum (greater than 1/6400), but showed no reaction with normal rat serum proteins and only very low binding to purified human IgE. In addition the binding of anti-peptide sera to rat IgE could be completely inhibited with either homologous peptide or purified rat IgE, but not by other peptides or purified human IgE. Heating rat IgE for 1 hr at 56 degrees C enhanced its binding to anti-peptide antibodies by between 4- and 60-fold, but markedly reduced its reactivity with a rabbit anti-rat IgE (Fc) serum. These results suggest that antibodies directed against the synthetic peptides employed recognize and specifically bind to sites within the CH4 domain of rat IgE represented by their respective immunizing peptides. Furthermore, these antibodies are capable of detecting subtle alterations in structural conformation resulting from heating at 56 degrees C. Epitopes represented by peptides P123 and P124 may contribute to the heat-sensitive cytophilic region of rat IgE.
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PMID:Use of synthetic peptides in the production and characterization of antibodies directed against predetermined specificities in rat immunoglobulin E. 370 75

The antiprotozoal drug pentamidine can be toxic to islet cells in vivo and in vitro. Rat islets were exposed to pentamidine (mesylate and isethionate salts) and six other structurally related diamidines. The beta-cell response to arginine + theophylline was suppressed by pentamidine (10(-2) mmol/l) while the glucagon and somatostatin secretions persisted. All diamidines tested suppressed the beta-cell function, with a log-dose-response proportionality, the mesylate compound being more potent than pentamidine isethionate, and the lipophilic analogs more than the hydrosoluble diamidines. Electron microscopy revealed distinct morphological alterations in islets exposed to pentamidine, the intensity of these changes being dose-and time-dependent, and the beta cells more severely damaged than the non-beta cells. 51Cr-labelled islet cells and RIN 5 F cells consistently appeared more sensitive to pentamidine cytotoxicity than rat fibroblasts, myeloma cells and hepatocytes. The pentamidine-induced suppression of beta-cell function was not, in conditions tested, affected by the presence of nicotinamide and the hexose concentration in the medium. The kinetics of islet damage were slower than those of streptozotocin and alloxan-induced islet damage. The present study confirms that pentamidine is selectively toxic to islet beta cells, with some features distinct from the alloxan and streptozotocin toxicities to these cells. The mechanism of this process and its precipitating factors in vivo need clarification.
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PMID:Functional and morphological modifications induced in rat islets by pentamidine and other diamidines in vitro. 389 20

Spleen cells of BALB/c mice, immunized with fragments Y of normal human fibrinogen, were fused with P3 X 63 Ag 8653 myeloma cells. A clone was found which produces monoclonal antibodies (Mab-Y18) of the IgM kappa type. Mab-Y18 is immunoreactive with normal human fibrinogen, and its fragments X, Y, N-terminal disulphide knot, A alpha-chain, and A alpha stretch 1-51. The immunoreactivity with these same fragments disappears upon treatment with thrombin or arvin. This strongly suggests that fibrinopeptide A is an essential component of the Mab-Y18 epitope. This is supported by the finding that Mab-Y18 prolongs the thrombin and arvin clotting times of human fibrinogen by inhibition of the fibrinopeptide A release. More detailed information about the nature of the Mab-Y18 epitope was obtained from studies with genetic variants of human fibrinogen (especially fibrinogen Metz) and with fibrinogens from other mammalian species. These studies show that amino acid residue A alpha 16 (arginine) of fibrinopeptide A is essential for the Mab-Y18 epitope. Mab-Y18 does not react with free fibrinopeptide A.
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PMID:A monoclonal antibody, specific for human fibrinogen, fibrinopeptide A-containing fragments and not reacting with free fibrinopeptide A. 404 Jul 83

Glycopeptides have been isolated from tryptic digests of kappa-type light chains separated from human myeloma proteins obtained from the serum of two patients, Car and Rai. The glycopeptides are derived from the variable region of the chain in both cases, but from different sections. On the basis of homology it is deduced that glycopeptide from Car, kappaI type, is derived from position 25-31 whereas that from Rai, kappaII type, is from position 62-77, their sequences being respectively Ala-Ser-Gln-Asn-Ile-Ser and Phe-Ser-Gly-Ser-Gly-Ser-Gly(Thr,Asp)Phe-Thr-Leu-Asx-Ile-Ser-Arg. The significance of the results is discussed in connexion with the nature of the attachment site of carbohydrate to protein.
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PMID:Glycopeptides from human kappa-chains. 511 28

An organ-specific alkaline phosphatase inhibitor, L-homoarginine, at 44.5 mM concentration inhibited [3H]thymidine uptake by C3H/He mouse osteosarcoma (OS) cells, while L-arginine, L-phenylalanine, and glycine had little effect on the uptake. This inhibitory effect of L-homoarginine persisted even after the cells were washed free of the amino acid with fresh media. L-Homoarginine did not affect [3H]thymidine uptake by mouse myeloma MOPC 104E cells. In long-term culture, 22.3 mM L-homoarginine inhibited proliferation of OS cells. L-Arginine at the same concentration inhibited the proliferation to a lesser extent. On the other hand, L-phenylalanine and glycine did not affect in vitro proliferation of OS cells. When the same number of viable OS cells was inoculated s.c. after culturing the 24 hr with 44.5 mM L-homoarginine or L-arginine, the tumor growth in mice given injections of L-homoarginine (but not L-arginine)-treated cells was delayed markedly. Electron microscopic studies indicated that the inhibiting effect on OS cell proliferation was associated with a marked increase in lysosomal granules and a decrease in virus-like structures. Similarly, biochemical assay for acid phosphatase of cell homogenates demonstrated a 2-fold increase of activity in L-homoarginine-treated cells when compared to controls and L-arginine-treated cells. Thus, L-homoarginine inhibits proliferation and alkaline phosphatase activity of mouse OS cells and appears to increase acid phosphatase activity in synthesis of lysosomal granules.
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PMID:Inhibitory effect of L-homoarginine on murine osteosarcoma cell proliferation. 617 11

We have produced several monoclonal antibodies which appear to be directed against different antigenic determinants of rat plasma fibronectin. Fibronectin was purified from rat plasma by affinity chromatography on gelatin-Sepharose and arginine-Sepharose columns. Mice were immunized and hybridomas were prepared by fusing spleen cells with Sp2/0-Ag14 myeloma cells using poly(ethylene glycol). Three hybridomas (RFN1, RFN2 and RFN3) were selected for characterization. All are IgG molecules, one is IgG2a, one IgG2b and one IgG1. Titers of ascites fluids produced using these hybridomas range from 102 400 to greater than 409 600. The antibodies cross-reacted to different degrees with human fibronectin. Rat fibronectin was radioactively labeled and cleaved using human polymorphonuclear leukocyte elastase. Four major peptides, Mr approx. 160 000, 140 000, 60 000 and 30 000 were produced. Each of the hybridoma antibodies immunoprecipitated different elastase peptides. RFN1 precipitated the Mr 160 000 peptide, RFN2 precipitated the Mr 160 000 and the Mr 140 000 peptide and RFN3 precipitated the Mr 60 000 peptide as well as low molecular weight material migrating at the buffer front. These antibodies will be useful in studies of structure/function relationships of rat fibronectin.
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PMID:Production and preliminary characterization of monoclonal antibodies to rat plasma fibronectin. 618 52

An organ-specific alkaline phosphatase (AIP) inhibitor, L-homoarginine at 44.5 mM concentration inhibited 3H-thymidine uptake by mouse C3H/He osteosarcoma (OS) cells, while L-arginine, L-phenylalanine and L-glycine had little effect on the uptake. This inhibitory effect by L-homoarginine persisted even after the cells were washed free of the amino acid with fresh media. L-homoarginine did not affect 3H-thymidine uptake by mouse myeloma MOPC 104E cells. In the long-term culture, 22.3 mM L-homoarginine inhibited proliferation of OS cells. L-Arginine at the same concentration inhibited the proliferation to a lesser extent. On the other hand, L-phenylalanine and L-glycine did not affect in vitro proliferation of OS cells. When similar numbers of viable OS cells were inoculated s. c. after culturing with 44.5 mM L-homoarginine or L-arginine for 24 hr, the tumor growth in mice injected with L-homoarginine (but not L-arginine) treated cells was delayed markedly. Electron microscopic studies indicated that the inhibitory effect on OS cell proliferation was associated with a marked increase in lysosomal granules and a decrease in virus-like structures. Similarly, a biochemical assay of acid phosphatase (AcP) of the cell homogenates demonstrated two-fold increase of the activity in L-homoarginine treated cells when compared to the controls and L-arginine treated cells. Thus, L-homoarginine inhibits proliferation and AIP activity of mouse OS cells and appears to promote cell differentiation as evidenced by the increased synthesis of cytoplasmic granules and acid phosphatase activity.
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PMID:[Inhibitory effect of L-homoarginine on murine osteosarcoma cell proliferation]. 619 5

Phosphorus-31 nuclear magnetic resonance (NMR) studies on the two phosphorus nuclei of the phosphonium analogue (Me3P+CH2CH2OPO3(2-)) of phosphocholine are used to monitor the charged subsites in the phosphocholine-binding immunoglobulin A mouse myeloma M603. Comparison of the 270-MHz 1H NMR difference spectrum on addition of either this analogue or phosphocholine to M603 and the almost identical changes in the pKa values of the phosphate groups on binding to M603 confirm that the analogue is a good model for phosphocholine. The pKa of the phosphate groups is decreased by 0.5 unit on binding to M603, which is consistent with the phosphate group being hydrogen bonding to Tyr-33H and Arg-95L, as suggested from the X-ray structure, and also implies that the binding energies for the mono- and dianion are similar. The P+Me3 moiety is used to probe the electrostatic interactions in the choline subsite. Titration of the chemical shift of the phosphonium phosphorus reflects a group on the protein that has a pKa value of less than or equal to 5, which from the refined X-ray structure (D.R. Davies, personal communication) of the site is assigned to Asp-97L. The choline subsite is monitored by using 1H NMR difference spectra, which indicates that the subsite is highly aromatic as expected from the crystal structure that places Trp-107H and Tyr-100L in this subsite. The ring current interactions from these rings can account for the 1H NMR chemical shift data on choline.
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PMID:A combined proton and phosphorus-31 nuclear magnetic resonance investigation of the combining site of M603, a phosphocholine-binding myeloma protein. 629 93

Monoclonal antibodies KS1/4, KS1/9, and KS1/17 were developed in this laboratory from a fusion of the murine myeloma cell line P3X63Ag8 with spleens of BALB/c mice previously primed with UCLA P3 cells derived from a human adenocarcinoma of the lung. Monoclonal antibodies KS1/4 and KS1/17 seemed to recognize similar glycoprotein antigens on the lung carcinoma cells by indirect immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. However, mapping of [3H]lysine- and [3H]arginine-labeled tryptic peptides of antigens in specific immunoprecipitates of lung carcinoma cells by high-pressure liquid chromatography revealed a one peptide difference. Antibody KS1/9 did not immunoprecipitate any identifiable protein from detergent extracts of the immunizing cell line by routine methods and appears to detect a glycolipid antigen. Immunocytochemical analysis of tissue sections showed this monoclonal antibody to be reactive with adenocarcinomas of the lung and not with the other histological types of lung carcinoma or normal tissue. Monoclonal antibodies KS1/4 and KS1/17, however, reacted with 3 major histological types of lung cancer and minimally with the proximal tubules of normal kidney and the epithelium of bronchioles.
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PMID:Antigens associated with a human lung adenocarcinoma defined by monoclonal antibodies. 636 52

A hybridoma cell line (26-10) derived from the A/J strain of mice secretes an immunoglobulin (IgG2a-k) which binds digoxin with an association constant of 1.2 nM. Such high-affinity antibodies have been utilized in clinical radioimmunoassays as well as in the reversal of toxicity due to excess digoxin. The amino acid sequence of the light chain variable region of this antibody was derived by automated sequencing of the following: the intact chain; a fragment beginning C terminal to the tryptophan residue 40, obtained by cleavage with iodosobenzoic acid; a fragment beginning C terminal to arginine residue 82, obtained by trypsin cleavage on the completely reduced, alkylated, and succinylated chain. Difficulties which had previously prevented the automated Edman sequencing of this chain (and, presumably, similar ones of the same subgroup) were overcome by increasing the duration of the cleavage step at proline residues 8 and 12. The sequences of the first two hypervariable and framework regions of this chain are virtually identical with those of the dinitrophenol- and menadione-binding myeloma light chain MOPC 460 (95% homology). This anti-digoxin hybridoma from the A/J strain makes use of a Vk gene which is similar to that utilized by some BALB/c 2,4-dinitrophenol-binding myelomas.
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PMID:Amino acid sequence of the light chain variable region from a mouse anti-digoxin hybridoma antibody. 640 98


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