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

We report here that cultured human lymphoma cells in the absence of sonicated eosinophils are sensitive to killing by glucose oxidase (beta-D-glucose:oxygen-oxido reductase; EC 1.1.3.4) at concentrations as low as 0.025 microgram/ml, a level that can be rapidly attained in s.c. tumor implants in mice that receive a single nonlethal injection of enzyme. Multiple clonogenic assays were used to measure the survival of human lymphoma cell lines (H9 and ARH-77) cultured for 14 days in complete RPMI 1640 supplemented with exogenous glucose oxidase (0.025-2.5 micrograms/ml) or an immunoconjugate containing glucose oxidase (0.25-25 micrograms/ml) in the presence or absence of catalase (10 micrograms/ml) or an equal number of sonicated human eosinophils with or without supplemental 100 microM Br-, I-, or SCN-. In addition, we used an immunoassay to measure the concentration of glucose oxidase in s.c. implants of the Sp 2/0 myeloma tumor at 0-30 min after an i.v. injection of 50 micrograms of enzyme into 21 BALB/c mice. Doses of glucose oxidase as small as 0.025 microgram/ml killed more than 3 logs of tumor cells. Catalase completely inhibited, and sonicated human eosinophils partially inhibited, the killing by glucose oxidase or immunoconjugate, whereas supplemental halides had no effect. Glucose oxidase i.v. produced levels > 0.04 microgram/g of tumor for 30 min after injection with a peak concentration of 0.079 microgram/g of tumor within 5 min of injection. These results are important because certain human lymphomas contain extensive extracellular deposits of eosinophil peroxidase, thereby making these tumors potentially less susceptible to killing by otherwise therapeutic doses of glucose oxidase.
...
PMID:Effects of sonicated eosinophils on the in vitro sensitivity of human lymphoma cells to glucose oxidase. 816 93

Macrophage cell-surface protein 2 (Mac-2), a galactose specific S-type lectin identified in inflammatory macrophages, presents a high degree of homology with the rat IgE-binding protein (epsilon BP). In the present study, we show by different experimental approaches that human eosinophils can express Mac-2/epsilon BP. Flow cytometry analysis revealed that a large proportion of eosinophilic patients expressing binding sites for IgE on their eosinophil membrane, were able to bind anti-Mac-2 monoclonal antibody (mAb). Northern blot performed with eosinophil RNA hybridized with the human Mac-2 or epsilon BP cDNA probes revealed that eosinophils presented a unique transcript at 1.2 kb. Immunoprecipitation of eosinophil extracts with anti-Mac-2 mAb revealed the presence of a molecule of 29 kDa corresponding to Mac-2 protein, as well as one additional molecule of 15 kDa, absent from control alveolar macrophages. The function of these molecules was investigated in a radiolabeled IgE binding assay. Anti-Mac-2 mAb as well as galactose and lactose saccharides significantly inhibited the binding of radiolabeled human myeloma IgE protein to eosinophils. Moreover, the dose-dependent inhibition by anti-Mac-2 mAb of IgE-dependent eosinophil-mediated cytotoxicity towards parasite targets indicated the role of these IgE-binding molecules in the function of human eosinophils. These results suggest that in addition to transmembrane receptors, lectin-type molecules can participate in the IgE-dependent effector function of eosinophils.
...
PMID:IgE-binding molecules (Mac-2/epsilon BP) expressed by human eosinophils. Implication in IgE-dependent eosinophil cytotoxicity. 825 38

It has been shown previously that secretory IgA interacts with the mannose-specific lectin of Escherichia coli. The purpose of the study described here was to evaluate whether the N-linked oligosaccharide chains of the human IgA isotypes IgA1 and IgA2 differ in lectin receptor activity. A range of plant lectins specific for N-linked oligosaccharide chains were tested for their ability to precipitate IgA1 and IgA2 myeloma proteins, secretory IgA and free secretory component. IgA2 myeloma proteins reacted more strongly than IgA1 with the mannose-specific lectin ConA, whereas IgA1 myeloma proteins reacted more strongly than IgA2 with two galactose-specific lectins, Ricinus communis agglutinin I and Abrus precatorius agglutinin. This suggests that IgA2 possesses a larger proportion of short truncated complex type oligosaccharide chains and/or oligomannose type chains than IgA1. Further, IgA2 reacted more strongly than IgA1 myeloma proteins with Lens culinaris (lentil) lectin, and Pisum sativum (pea) lectin, suggesting that IgA2 exposes more of short, complex type chains fucosylated on the core than IgA1. The differences demonstrated in receptor activity between IgA1 and IgA2 may be important in their interaction with the microbial flora, as well with endogenous lectins, such as phagocyte receptors.
...
PMID:Lectin receptors on IgA isotypes. 829 63

Assay of the activity of beta-1,4-galactosyltransferase (beta-1,4-GT) revealed that in addition to serum, milk, colostrum, amniotic and cerebrospinal fluids and malignant effusions, this enzyme is present also in tears and saliva. Molecular-sieve chromatography of human colostral whey and serum and subsequent assay of beta-1,4-GT activity have shown that beta-1,4-GT was present as a free enzyme (55 kDa) and associated with components of larger molar mass. The elution pattern did not change when the chromatography was carried out in a buffer devoid of, or enriched with, Mn2+, a cofactor of beta-1,4-GT activity. However, the activity associated with the large molar mass components was absent when the chromatography was carried out in the presence of a chelating agent (EDTA). Analyses of the eluted material by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE), and by immunodiffusion indicated that the major colostral component in beta-1,4-GT activity-containing fractions was secretory IgA (S-IgA); in addition, the beta-1,4-GT activity was detected in fractions that contained lactoferrin and alpha-lactalbumin. Interactions of beta-1,4-GT with S-IgA and lactoferrin in colostrum were also demonstrated by the detection of radioactivity in precipitin lines obtained by immunoelectrophoresis and autoradiography of the colostral whey after it had been incubated with UDP-[3H]-galactose. Furthermore, radioactively labeled S-IgA and alpha-chain were detected when colostral whey incubated with UDP-[3H]-galactose was analyzed by SDS-PAGE under non-reducing and reducing conditions, respectively. In serum, the beta-1,4-GT-binding components identified in fractions after molecular-sieve chromatography were IgG, IgA, IgM and transferrin. The binding of beta-1,4-GT to immunoglobulins (Ig) was also demonstrated by assaying the beta-1,4-GT activity associated with Sepharose-4B-immobilized Ig of various isotypes and molecular forms, which were incubated with colostral beta-1,4-GT in the presence of Mn2+. Beta-1,4-GT measured by enzyme activity was bound to these Ig in order: polymeric IgA2 > monomeric IgA1 = polymeric IgA1 = secretory IgA = pentameric IgM > IgG. Immobilized component chains, namely alpha, mu and J chains, bound beta-1,4-GT more effectively than native Ig. Incubation of the IgA1 myeloma protein with crude human colostral galactosyltransferase in the presence of UDP[3H]-galactose and Mn2+ resulted in galactosylation of both N- and O-linked carbohydrate side chains.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Interactions of galactosyltransferase with serum and secretory immunoglobulins and their component chains. 843 6

Mediastinal masses include a wide variety of tumours and remain an interesting diagnostic challenge for radiologist. We performed positron emission tomography (PET) studies of primary mediastinal tumours in order to predict the malignancy of these tumours preoperatively. Twenty-two patients with primary mediastinal tumours were studied with PET using 2-deoxy-2-[18F]fluoro-D-glucose (FDG). The histological findings of surgical pathology or biopsy, or mediastinoscopy were compared with those of computerised tomography (CT) and PET. PET images were evaluated semiquantitatively using the differential uptake ratio (DUR). Increased FDG uptake was observed in nine of ten patients with malignant tumours, including thymic carcinomas, lymphomas, invasive thymomas and a case of sarcoidosis. A moderate level of FDG uptake was found in a myeloma, non-invasive thymomas, and a schwannoma, whereas a low uptake was observed in a teratoma and various benign cysts. The mean FDG uptake of malignant tumours was significantly higher than that of benign tumours. Both thymic cancer and invasive thymoma showed a high FDG uptake. CT examination resulted in three false-negative and two false-positive cases when used in predicting tumour invasion, while PET was associated with a false-positive and a false-negative case. In conclusion, the use of FDG with PET is clinically helpful in evaluating the malignant nature of primary mediastinal tumours. Our results also suggest that a high FDG uptake reflects the invasiveness of malignant nature of thymic tumours.
...
PMID:PET imaging of primary mediastinal tumours. 861

Sialylated oligosaccharide structures were determined by the technique of electrospray ionization mass spectroscopy at seven of eight N-linked glycosylation sites of recombinant human ICAM-1des454-532 [tICAM(453)] purified from the tissue culture fluid of Chinese hamster ovary, human embryonic kidney, and mouse myeloma cell lines. The number of structures at each site depended on the cell line and ranged from 8 to 34. N-Glycolyneuraminic acid, a human oncofetal antigen, was found at all sites of all three cell line derived forms of tICAM(453). Tetraantennary complex structures containing one and/or two galactose-beta 1,4 N-acetylglucosamine repeats, characteristic of membrane bound proteins, were found on soluble tICAM(453) primarily at Asn-379. Asn-379, located between the D4 and D5 domains, is believed to be located close to the membrane surface in membrane bound ICAM-1. It has been proposed that the extent of N-linked glycosylation at Asn-240 and Asn-269 in the third domain of ICAM-1 may regulate the binding avidity of ICAM-1 to Mac-1 [Diamond, M. S., Staunton, D. E., Marlin, S. D., & Springer, T. A. (1991) Cell 65, 961-971]. In the present study the tICAM(453) Asn-269 site was found to contain predominantly one oligosaccharide structure that is conserved in all three cell lines. On the other hand, the Asn-240 site was found to contain cell line dependent oligosaccharide structural heterogeneity particularly in the degree of sialylation.
...
PMID:Cell line and site specific comparative analysis of the N-linked oligosaccharides on human ICAM-1des454-532 by electrospray ionization mass spectrometry. 863 67

In a woman suffering from IgE myeloma, hay fever and polyvalent respiratory and skin allergy the IgE monoclonal protein VL was isolated and investigated with respect to structural and functional properties. The amino acid sequence of 22 isolated peptides--especially of the biologically significant C2-C3 part--corresponded with that originally described by Bennich et al. (Immunol Rev 1978;41:3-23; Prog Immunol 1974;13:49-58). However, in mass spectrometry the sugar residues on ASN 99 (219) and 252 (371) were deficient in sialic acids. The native IgE VL protein precipitated with high intensity all mannose-specific lectins as concanavalin A (Con A) and was able to release histamine after triggering by these lectins. The same lectins also elicited more histamine release and more positive skin reactions in atopic than in healthy persons. In sera from atopic patients the binding of IgE on Con A Sepharose 4B column was stronger than in normal persons. It is suggested that changes in the IgE glycosylation state may contribute to IgE-mediated pictures of clinical allergy by the nonimmunological pathway.
...
PMID:Structure and function of IgE myeloma protein VL from an atopic patient. 864 91

In our previous study, gas-phase hydrazinolysis was used to analyze the glycoform of the O-linked oligosaccharide of human serum IgA1. All O-linked oligosaccharide chains are known to be present in the hinge portion. However, the number of O-linked oligosaccharide chains on IgA1 remained unclear. In order to determine the number of linked sugar chains, we applied matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) to the hinge glycopeptide prepared from human serum IgA1. MALDI-TOFMS did not show clear peaks, probably due to the microheterogeneity of the structure of each sugar chain. However, elimination of peripheral sialic acid and galactose residues by sequential treatment with neuraminidase and beta-galactosidase gave clear mass spectra with several sharp peaks. On the basis of these spectra, we conclude that IgA1 prepared from normal human serum carries different numbers of sugar chains. There are two major populations, one contains five GalNAc residues and the other four GalNAc residues. On the other hand, the hinge glycopeptide prepared from myeloma IgA1 was composed mainly of one population containing four GalNAc residues. Earlier, we reported incomplete glycosylation of IgA1 isolated from the serum of an IgA1 myeloma patient. In this experiment, the presence of four O-linked oligosaccharides per heavy chain of IgA1 from a myeloma patient was found. The reason why only four out of five sites on the hinge glycopeptide were fully glycosylated in the IgA1 from the IgA1 myeloma patient is not clear.
...
PMID:Estimation of the number of O-linked oligosaccharides per heavy chain of human serum IgA1 by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis of the hinge glycopeptide. 888 26

The molecular mechanism underlying the interaction between myeloma cells and stromal cells was investigated by using a human myeloma cell line (OPM-2) and human umbilical vein endothelial cells (HUVECs). Adhesion of OPM-2 cells to HUVECs was found to be significantly augmented with treatment of OPM-2 cells with an alpha-glycosidase inhibitor, castanospermine (CSP). The treatment of OPM-2 cells with CSP resulted in alteration of oligosaccharide structures of cell surface glycoproteins particularly at molecular weight of 220 kD (GP220). To determine if GP220 was involved in the adhesion of OPM-2 cells to HUVECs, cell surface glycoproteins of HUVECs were labeled by biotin and were incubated with the PVDF membrane to which cell surface glycoproteins of OPM-2 cells were blotted. The biotinylated glycoproteins at the plasma membrane of HUVECs specifically bound to GP220 of OPM-2 cells. Purification and partial amino acid sequencing of GP220 revealed that GP220 had a structure homologous to cation-independent mannose 6-phosphate/insulin-like growth factor-II (CIM6P/IGF-II) receptor. Furthermore, an antibody against CIM6P/IGF-II receptor was reactive with GP220, indicating that GP220 was a CIM6P/IGF-II receptor. The adhesion of OPM-2 cells to HUVECs was inhibited by mannose 6-phosphate. Moreover, M6P was found to suppress the adhesion of human myeloma cell lines, OPM-2 and RPMI 8226, to bone marrow stromal cells that was established from the patients with multiple myeloma. In addition, proliferation of OPM-2 was stimulated in response to IGF-II. These results suggest that CIM6P/IGF-II receptor may be functional in terms of supporting cell adhesion and proliferation of myeloma cells.
...
PMID:Functional role of cation-independent mannose 6-phosphate/insulin-like growth factor II receptor in cell adhesion and proliferation of a human myeloma cell line OPM-2. 889 22

Mouse monoclonal antibodies MAHI 4 and MAHI 10 reactive with Haemophilus influenzae lipopolysaccharide (LPS), were generated by fusing mouse myeloma cells with spleen cells of mice immunized with H. influenzae strain RM.7004-XP-1. The antibody MAHI 4 reacted in whole-cell enzyme immunoassay (EIA) and colony-dot-immunoblotting with 20 of 123 H. influenzae strains and to a few other human Haemophilus spp. and Neisseria spp., but not to any Bordetella pertussis, B. parapertussis, Aeromonas spp. or Moraxella catarrhalis strains tested. This suggests a specific epitope accessible to recognition in just a few strains. This conclusion was supported by the data on binding of MAHI 4 to only three of 18 H. influenzae LPSs tested, but not to any Haemophilus ducreyi or enterobacterial LPSs. The antibody MAHI 10 bound to 80 of 123 strains of H. influenzae and to a few strains of Neisseria spp. and M. catarrhalis as evaluated by EIA and colony-dot-immunoblotting, which suggests an epitope accessible to recognition in 65% of the H. influenzae strains tested. The antibody MAHI 10 reacted with 10 of 18 H. influenzae LPSs as determined by EIA. By using polysaccharides, obtained after both mild acidic hydrolysis, strong alkali treatment, and dephosphorylation, as inhibitors of the antibodies binding to H. influenzae LPS antigens it was shown that phosphate groups were essential for the binding of MAHI 10 to LPS but they did not affect antigenic recognition by MAHI 4. None of the monoclonal antibodies bound to isolated lipid A, but the aggregation caused by the fatty acids of lipid A was essential for optimum epitope recognition. Enzymatic treatment of homologous LPSs with galactose-oxidase led to products which were between 20 to 30 times less effective as inhibitors of the binding of the MAHI 4 than the native LPSs. Taken together the results indicate that MAHI 4 has the following pentasaccharide as the epitope Gal beta 1-->2 Hep alpha 1-->2Hep alpha 1-->3Hep alpha 1--> Kdo(P). These results emphasize the importance of the terminal beta-Gal residue in the definition of the MAHI 4 specificity, and of the terminal phosphorylated saccharide residues of some of the Haemophilus LPSs for the MAHI 10 specificity.
...
PMID:Monoclonal antibodies against Haemophilus influenzae lipopolysaccharides: clone MAHI 4 binding to a pentasaccharide containing terminal beta-Gal residues and clone MAHI 10 recognizing terminal phosphorylated saccharide residues. 893 39


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>