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)

The structure and antigenic characteristics of a human k, IgG myeloma protein that formed half-molecules were analyzed. Most of the myeloma protein found in the patient's serum and urine consisted to two chain 4.3S half-molecules. A small amount of four chain 7S myeloma protein was, however, found in the serum and was apparently formed by the same clone of tumor cells. Polyacrylamide gel electrophoresis in 8 M urea and 1% sodium dodecyl sulfate and analytical ultracentrifugation in 6 M guanidine of the fully reduced and alkylated half-molecule indicated that this myeloma protein had a heavy chain of a smaller molecular weight (approximately 45,000) than that of normal gamma chains, Except for this apparent deletion, the heavy chain resembled gamma1 chains. The amino acid composition of the peptides containing the half-cysteine residues forming the interchain disulfide bonds, the glycopeptide of the Fc fragment and the COOH-terminal structure were similar if not identical with the analogous structures of gamma1 chains. No Fc fragment could be prepared because the Fc portion of the heavy chain of the myeloma protein was extremely susceptible to degradation with papain. After mild reduction and alkylation, the 7S myeloma protein dissociated into half-molecules, indicating a lack of noncovalent interactions in the Fc fragment that are present in all classes of human immunoglogulins and are responsible for the formation ofFc dimers. The half-molecule was antigenically deficient in the Fc fragment. It failed to precipitate with anti-Fc fragment antisera in double gel diffusion tests and inhibited a Fc-anti-Fc fragment binding reaction weakly and incompletely. The half-molecule and the 7S protein had the same genetic markers on the first and second homology region of the gamma chain. The half-molecule lacked, however, the corresponding markers on the third homology region, These findings suggest that this myeloma protein had a deletion in the gamma chain which was probably located in third homology region and was likely the structural abnormality responsible for the lack of noncovalent interaction in the Fc fragment and absence of most of the antigenic determinants characteristic of gamma chains.
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PMID:Human myeloma IgG half-molecules. Structural and antigenic analyses,. 5 83

Infection of mouse myeloma cells (MPC-11) with vesicular stomatitis (VS) virus resulted in rapid and marked reduction in cellular RNA synthesis considerably before cell viability was compromised. Mouse myeloma cells responded maximally to viral infection at a multiplicity of 1 and were considerably more se;sitive to shut-off of RNA synthesis than were mouse L cells or BHK-21 cells. This inhibition of cellular RNA synthesis was shown not to be caused by differential membrane permeability of infected and uninfected MPC-11 cells to [3H]uridine, nor was it due to greater degradation of previously synthesized RNA. VS viral infection appeared not to impede transport of newly synthesized nuclear RNA to the cytoplasm; moreover, infected cells accumulated polyadenylated mRNA at the same rate as did uninfected cells. Polyacrylamide gel electrophoresis of newly synthesized nuclear RNA demonstrated that the polydisperse nature and size distribution were not affected by VS viral infection. Isolated nuclei of infected MPC-11 cells also inhibited greatly impaired capacity to synthesize RNA despite the absence of cytoplasmic factors. Infected-cell cytosol did not inhibit transcription by uninfected-cell nuclei, nor did uninfected-cell cytosol reverse viral inhibition of nuclear transcription. Studies with alpha-amanitin revealed that VS viral infection inhibited the activity of polymerases I, II, and III, but only polymerase II was affected progressively throughout infection and to a much greater extent. These data suggest that, even at low multiplicities of infection, VS virus rapidly shuts off cellular RNA synthesis at the level of nuclear transcription.
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PMID:Inhibition of RNA synthesis in mouse myeloma cells infected with vesicular stomatitis virus. 20 71

Affinity chromatography of IgG on protein A-Sepharose was used to isolate the human subclass IgG3 from normal serum and from a patient with multiple myeloma. The isolated material was purified by chromatography on Sephadex G-150 and characterized immunochemically. Ultracentrifugation studies gave so20,w values of about 6.80 for both normal and myeloma IgG3. Approximately 54 half-cystine residues per molecule of IgG3 were obtained as judged from amino acid analysis after performic acid oxidation of the proteins. Polyacrylamide gel electrophoresis in 0.1% sodium dodecyl sulfate of the isolated and reduced material resulted in two bands corresponding to molecular weights of approximately 23,000 and 56,000, respectively. The yield of normal human IgG3 represented 1%-2% of the total IgG.
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PMID:Isolation of IgG3 from normal human sera and from a patient with multiple myeloma by using protein A-sepharose 4B. 81 76

A mutant cell line (IF2) derived from the mouse myeloma MOPC 21 has been used for the isolation and sequence analysis of H-chain mRNA. The IF2 cells synthesise an H-chain of reduced size in which the CH1 homology region is missing. Sizing of the IF2 H-chain mRNA and wild-type H-chain mRNA revealed that the deletion is expressed at the mRNA level. The mutant H-chain mRNA sedimented at 16-S, enabling effective resolution from 18-S ribosomal RNA. In experiments using IF2 cells labelled with [32P]phosphate, the 16-S mRNA was purified by oligo(T)-cellulose chromatography. Polyacrylamide gel analysis of the poly(A)-containing fraction showed the presence of a single radioactive band. Comparison of the mobility of this band relative to markers of known molecular weight revealed that the molecule contained about 1600 nucleotides. Digestion of the 32-P-labelled mRNA with T1 ribonuclease and two-dimensional fractionation of the resulting oligonucleotides yielded a 'finger-print' suitable for a preliminary sequence analysis. By using the established amino acid sequence of the IF2 H-chain and a knowledge of the genetic code, 14 oligonucleotides were assigned within the constant region and four within the variable region of the IF2 H-chain. This sequence data accounts for 19.5% of the coding region. Several other oligonucleotides, which could not be assigned within the coding region but which occurred in approximately molar yield, have also been partially characterised. These oligonucleotides are presumably derived from the untranslated regions of mRNA.
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PMID:Purification and sequence analysis of the mRNA coding for an immunoglobulin heavy chain. 81 96

It has been demonstrated previously that the degree of glycosylation of a molecule may alter its pharmacokinetic properties and, in the case of an antibody, its metabolism and other biological properties. Transfectomas producing aglycosylated chimeric B72.3(gamma 1) pancarcinoma monoclonal antibody (mAb) were developed by introduction of the eukaryotic expression construct pECMgpB72.3 HuG1-agly, into SP2/0 murine myeloma cells producing the chimeric kappa chain of mAb B72.3. After cell cloning, one subclone with the highest binding to the TAG-72-positive human colon carcinoma was designated mAb aGcB72.3, and its biological and biochemical properties were compared with those of the chimeric B72.3(gamma 1), designated mAb cB72.3. Polyacrylamide gel electrophoresis showed that under non-reducing conditions, the molecular masses of the aGcB72.3 and cB72.3 mAbs were 162 kDa and 166 kDa respectively. The heavy chain of mAb aGcB72.3 had a slightly faster mobility than that of cB72.3, while the mobility of the light chains of the two chimeric mAbs was similar. No difference was observed in the isoelectric points of either chimeric mAb. Liquid competition radioimmunoassays demonstrated that the aGcB72.3 and cB72.3 mAbs have comparable binding properties to TAG-72. These studies demonstrate that aglycosylation of the chimeric IgG1 mAb B72.3 at the CH2 domain, as has been shown for other mAbs [Dorai H., Mueller B., Reisfeld R. A., Gillies S. D. (1991) Hybridoma 10:211; Morrison S. L., Oi V. T. (1989) Adv Immunol 44:65], eliminates antibody-dependent cell-mediated cytotoxicity activity, but does not substantially alter affinity or plasma clearance in mice. These studies also demonstrate for the first time (a) no difference in plasma clearance of an aglycosylated and a chimeric mAb in a primate after i.v. inoculation; (b) a difference (P less than or equal to 0.05) in mice in the more rapid peritoneal clearance of a chimeric mAb versus an aglycosylated chimeric mAb; (c) higher (0.05 less than or equal to P less than or equal to 0.1) tumor: liver ratios at 24, 72 and 168 h using 111In-labeled aglycosylated chimeric mAb versus chimeric mAb. Since the liver is the major site of metastatic spread for most carcinomas, slight differences in tumor to normal liver ratios may be important in diagnostic applications. These studies thus indicate that comparative analyses of a novel recombinant construct (i.e., aglycosylated) and its standard chimeric counterpart require documentation in more than one system and are necessary if one is ultimately to define optimal recombinant/chimeric constructs for diagnosis and therapy in humans.
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PMID:Comparative biological properties of a recombinant chimeric anti-carcinoma mAb and a recombinant aglycosylated variant. 163 52

Human lung fibroblasts produce heparan sulphate proteoglycans (HSPG) that are associated with the plasma membrane. A monoclonal-antibody (Mab)-secreting hybridoma, S1, was produced by fusion of SP 2/0-AG 14 mouse myeloma cells with spleen cells from mice immunized with partially purified cellular HSPG fractions. The HSPG character of the material carrying the epitope recognized by Mab S1 was demonstrated by: (i) the co-purification of the S1 epitope with the membrane HSPG of human lung fibroblasts; (ii) the decrease in size of the material carrying the S1 epitope upon treatment with heparinase or heparitinase, and the resistance of this material to heparinase treatment after N-desulphation. The S1 epitope appears to be part of the core protein, since it was destroyed by proteinase treatment and by disulphide-bond reduction, but not by treatments that depolymerize the glycosaminoglycan chains and N-linked oligosaccharide chains. Polyacrylamide-gel electrophoresis of non-reduced heparitinase-digested membrane HSPG followed by Western blotting and immunostaining with Mab S1 revealed a single band with apparent molecular mass of 64 kDa. Membrane proteoglycans isolated from detergent extracts or from 4 M-guanidinium chloride extracts of the cells yielded similar results. Additional digestion with N-glycanase lowered the apparent molecular mass of the immunoreactive material to 56 kDa, suggesting that the core protein also carries N-linked oligosaccharides. Fractionation of 125I-labelled membrane HSPG by immuno-affinity chromatography on immobilized Mab S1, followed by heparitinase digestion and polyacrylamide-gel electrophoresis of the bound material, yielded a single labelled band with apparent molecular mass 64 kDa. Treatment with dithiothreitol caused a slight increase in apparent molecular mass, suggesting that the core protein of this membrane proteoglycan of a single subunit containing (an) intrachain disulphide bond(s).
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PMID:Identification of a 64 kDa heparan sulphate proteoglycan core protein from human lung fibroblast plasma membranes with a monoclonal antibody. 244 76

An IgG3 murine monoclonal antibody (designated MO8) specific for the serogroup C2 Salmonella lipopolysaccharide (LPS) was generated by fusing mouse myeloma cells NS1 with spleen cells of BALB/c mice immunised with heat-killed S. manhattan. MO8 reacted with purified LPS prepared from serogroup C2 Salmonella but did not react with that prepared from other O serogroups, and its reactivity was also specifically absorbed by serogroup C2 Salmonella only. Polyacrylamide gel electrophoresis of the serogroup C2 LPS and subsequent immunoblotting with MO8 yielded multiple reactive bands giving a characteristic ladder pattern. The specificity of MO8 was further demonstrated in the slide agglutination test with 223 bacteria, of which only 25 belonging to serogroup C2 Salmonella reacted with the MO8 ascitic fluid. The specificity of MO8 makes it useful not only for the serological identification of Salmonella but also for the epitope analysis of the serogroup C2 LPS.
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PMID:Characterisation and application of a murine monoclonal antibody specific for the serogroup C2 Salmonella. 245 55

Lymphocyte egress from the vascular compartment into the lymph node (LN) parenchyma occurs at the postcapillary venules, termed high endothelial venules (HEVs). Lymphocyte adhesion and migration through the HEVs is a receptor-mediated, energy-dependent, process. The aim of this study was to investigate the role of MHC Class II antigen expression on lymphocyte-HEV interaction in normal (CBA) and autoimmune (MRL/l) mice. Using the HEV binding assay, lymphocyte adhesion to LN sections pretreated with monoclonal antibody (MAb; 10-2.16) was decreased compared to diluent (mean of the differences +/- standard deviation; xd +/- SD: 0.749 +/- 0.22, P less than 0.0075)- and myeloma immunoglobulin-pretreated controls (xd = 0.462 +/- 0.13, P less than 0.005). Similar inhibition of binding was found in MRL/l LN sections pretreated with MAb 10-2.16. Binding inhibition was concentration dependent, but total inhibition was never achieved. Several other anti-Ia MAb's were used, but failed to inhibit lymphocyte attachment. Lymphocyte binding to control sections treated with MAb's against MHC Class I antigen, plasminogen activator (PAM-3), anti-thrombin III (AT-IIIm), and MECA-325 antigen was not significantly different from diluent controls. LN cell suspensions pretreated with MAb 10-2.16 bound normally to LN sections. By contrast, MAb to lymphocyte homing receptor (MEL-14) inhibited lymphocyte adhesion. The role of Class II antigens in lymphocyte-HEV interactions is discussed.
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PMID:Anti-Ia monoclonal antibody (10-2.16) inhibits lymphocyte-high endothelial venule (HEV) interaction. 318 Feb 28

Ovine secretory IgA (sIgA) has been purified to relative homogeneity by ammonium sulphate precipitation (to 40 per cent w/v) of lung lavage fluid from 3- or 12-month-old lambs, followed by molecular sieve chromatography on a Sephacryl S300 matrix. Three peaks A, B and C with molecular sizes corresponding to 550,000, 400,000 and 165,000 respectively were eluted from the column. Immunoelectrophoresis, radial immunodiffusion and enzyme-linked immunosorbent assays (ELISAs) with class specific antiserum confirmed that peak B contained only IgA. Polyacrylamide gel electrophoresis of peak B under reducing conditions resolved three subunits corresponding to secretory component, heavy and light chains. Hybridomas generated by fusing spleen cells from IgA-primed Balb/C mice with murine myeloma (Sp2/0) were screened for IgA-specific monoclonal antibodies against a panel of ovine IgG2, IgG1, IgA and IgM. One particular clone, F3-4B4, identified as murine IgG1, was monospecific against ovine IgA with no cross reactivity against bovine immunoglobulins. This hybridoma was successfully tested as a serological probe by ELISA profiling to locate IgA containing fractions in the course of immunoglobulin purification from biological fluids.
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PMID:Monoclonal antibodies against ovine IgA purified from lung lavage fluid. 376 94

An antigenic heterogeneity among IgD myeloma proteins was tested by immunoelectrophoresis and double immunodiffusion in agar with four kinds of anti-delta(Fc) antisera produced by immunization with isolated Fc fragments of IgD myeloma proteins. According to antigenicity of the Fc fragment, IgD myeloma proteins were divided into two different groups. Anti-delta(Fc)-T1 (S.T.) antiserum, absorbed with te Y.S. myeloma protein or serum, either gave a faint precipitin line or failed to react against the isolated IgD myeloma proteins or sera. With the papain-digested IgD myeloma proteins and sera, anti-delta(Fc)-T1 antiserum either gave heavy precipitin lines or failed to react. Of twelve papain-digested sera containing IgD myeloma proteins tested, nine (75%) showed positive precipitin lines using anti-delta(Fc)-T1 antiserum. No relationship was found between the two groups of myeloma proteins with respect to IgD levels. SDS polyacrylamide gel electrophoresis of the IgD myeloma proteins (S.T. and Y.S.) showed no difference in the molecular weights of the whole myeloma proteins, and their light and heavy chains. Polyacrylamide gel electrophoresis of the IgD myeloma proteins (S.T. and Y.S.), after treatment with papain, revealed almost the same patterns.
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PMID:Immunochemical studies on heterogeneity of IgD myeloma proteins. 616 63


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