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)

Freshly explanted human myeloma cells formed colonies of monoclonal plasma cells in soft agar in the presence of medium conditioned by the adherent spleen cells of mineral oil-primed BALB/c mice. The medium showed peak activity at a dilution of 1:4. 2-mercaptoethanol or monothioglycerol was necessary for colony formation. Other thiols tested were ineffective in promoting colony growth. Colony-forming cells adhered to nylon wool, but not glass beads or plastic dishes. The presence of E-rosetting cells was not required for myeloma colony formation. Antibody prepared against a human myeloma cell line, RPMI 8226, reduced colony formation. These studies demonstrate the usefulness of this bioassay for determining functional properties of the myeloma colony-forming cell.
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PMID:The nature of cells generating human myeloma colonies in vitro. 42 63

Dopamine inhibits prolactin release from pituitary cells and seems to affect the release of several other hormones as well. We report here that dopamine may have similar effects on human B lymphoma cells leading to inhibition of production or release of endogenous factors required for cell viability and proliferation. Thus, addition of dopamine to serum-free cultures of Burkitt lymphoma cells (Raji, Namalwa, Daudi and Jijoye) resulted in rapid and extensive cell death while a myeloma cell line, SKO, appeared to be refractory to this treatment. The addition of FCS or supernatant from serum-free cultures of Raji or T24 bladder carcinoma cells could, to a variable degree, counteract the effect of dopamine, suggesting that dopamine acts by inhibiting the production of essential autocrine factors. When two of the hormones known to be under dopamine control, i.e. prolactin (PRL) and thyrotropin (TSH), were tested, they were able to prevent dopamine-induced cell death if combined with heparin. We further observed that the reducing agent 2-mercaptoethanol (2-ME), which is known to inhibit the binding of TSH to its receptor, displayed similar effects to those of dopamine and was strongly inhibitory for Burkitt lymphoma but not for myeloma cells. As expected from its blocking activity at the receptor level, the effect of 2-ME could not be reversed by adding exogenous factors. Contrary to its effect on B lymphoma cells, 2-ME is essential for growth of the murine T-cell lymphoma line CTLL. However, we show here that dopamine can fully compensate for 2-ME, suggesting that TSH or another factor under dopamine control is intimately involved in the regulation of T-cell growth. This study lends further support to the notion of an active interplay between the neuroendocrine and immune systems and emphasizes PRL and TSH as important regulators of lymphoid cell function. It also shows that these hormones may contribute to the autonomous growth pattern of B lymphoma cells and suggests a potential role for dopamine in the treatment of B-cell tumours.
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PMID:Dopamine-induced lymphoma cell death by inhibition of hormone release. 141 1

Previous reports from our laboratory have described the binding specificity of a monoclonal antibody, D83.21, prepared by fusing P3X63/Ag8 mouse myeloma cells with mouse lymphocytes immunized against the DU145 human prostate adenocarcinoma cell line. The D83.21 monoclonal antibody displayed preferential binding to human prostate and bladder carcinoma cell lines and tissues. This antibody was not reactive with a variety of other normal and malignant human cell lines or tissues. Immunofluorescence analysis indicated that the D83.21 antigen was located on the plasma membrane. Biochemical characterization of the target antigen was performed by subjecting detergent-soluble extracts of [3H]glucosamine-labeled cells to D83.21 monoclonal antibody affinity chromatography. The radioactive material that was specifically bound and eluted from the affinity column was analyzed by sodium dodecyl sulfate:polyacrylamide gel electrophoresis and fluorography. In the absence of 2-mercaptoethanol, the antigen displayed two prominent bands with molecular weights of 180 and 110 kilodaltons. In the reduced form, the antigen is composed of an Mr 60,000 heavy chain and an Mr 28,000 light chain. The antigen was further resolved using two-dimensional (intact/reduced) sodium dodecyl sulfate: polyacrylamide gel electrophoresis. These analyses indicated that the Mr 180,000 chain was composed entirely of Mr 60,000 subunits, whereas the Mr 110,000 band consisted only of Mr 28,000 subunits. The antigen recognized by the D83.21 monoclonal antibody is therefore a membrane glycoprotein with a subunit structure cross-linked together through disulfide bonds.
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PMID:Disulfide bonding of a human prostate tumor-associated membrane antigen recognized by monoclonal antibody D83.21. 257 9

Monoclonal antibodies (MAbs), for human use require chemical and biological purity. The best approach seems in vitro cultivation in a serum-, protein-free medium. A basal defined culture medium has been developed to sustain optimal hybridoma cell growth and MAb secretion. It consists of Iscove's Dulbecco's modified, Eagle's, Ham's F12 and NCTC 135 media in a 5:5:1 mixture (v/v/v), to which glucose is added to reach a final concentration of 25 mM, glutamine to 4-6 mM, 2-mercaptoethanol to 50 microM, Pluronic F68 to 0.01-0.1% (w/v), Hepes to 25 mM and NaHCO3 to 3 g/l. Hybridoma cells, derived from Sp 2/0 myeloma and secreting a MAb to a human milk fat globule membrane-associated high molecular weight glycoprotein, were cloned in this medium containing 1% (v/v) fetal calf serum and then sequentially adapted in serum-free medium further supplemented with transferrin and insulin, both at 10 micrograms/ml. Clones producing immunoreactive MAbs secrete a mean of 50 micrograms IgG/ml, i.e., ca. 80% of the concentration reached in Dulbecco's modified Eagle's medium containing 10% serum. When cells were cultured in spinner flasks with a semi-continuous mode of cultivation (with a daily removal of 20% of the volume and its replacement by fresh culture medium), in serum-free medium further supplemented with 10 nM estradiol, a mixture of trace elements and albumin (at 30 micrograms/ml) complexed to linoleic acid, MAb secretion reached 100 micrograms/ml and became equal or higher to that obtained in serum-containing medium. MAb secretion was not decreased and was even significantly increased during the growth phase, when transferrin was replaced by another iron source, i.e., ferric citrate at 500 microM associated with 20 microM ascorbic acid. Finally, deletion of insulin and of albumin-linoleic acid did not affect significantly cell density nor MAb secretion. In conclusion, it appears from this study that semi-continuous cultivation in spinner flasks of hybridoma cells, after cloning and progressive adaptation, in a chemically defined, serum- and protein-free medium, permitted MAb secretion to be increased to a mean of 144 micrograms/ml, i.e., multiplied by a factor of ca. 1.5 compared to culture of these cells in serum-containing medium under the same conditions and by a factor of ca. 2.4 compared to cultivation in serum-containing medium in flasks.
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PMID:Optimisation of hybridoma cell growth and monoclonal antibody secretion in a chemically defined, serum- and protein-free culture medium. 264 56

We have constructed a chimeric aequorin consisting of a fragment of the anti-NP immunoglobulin gene fused to the aequorin gene. Expression in a myeloma cell line has produced a Fab'-like molecule that has the ability to bind NIP specifically and generate bioluminescent activity. It takes approximately 8 h at 4 degrees C in the presence of 2-mercaptoethanol and coelenterazine to regenerate luminescent activity. While the flash kinetics of this recombinant molecule are similar to native aequorin, its quantum efficiency is ten times lower. Preliminary studies have been conducted to ascertain its usefulness for immunoassays. We have shown for this chimeric aequorin 7 x 10(-19) moles can be detected in solution, also it can be used in a solid-phase assay and is stably stored at -70 degrees C for at least 2 months.
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PMID:Characterization of a chimeric aequorin molecule expressed in myeloma cells. 280 Dec 22

The secretion of immunoglobulin (Ig) from cultured mononuclear cells by lipopolysaccharide (LPS) stimulation is inhibited by monoclonal nonspecific suppressor factor (MNSF), a lymphokine produced by murine T cell hybridoma. In an attempt to develop a murine monoclonal antibody (MAb) with specific reactivity against MNSF, a cell fusion technique that incorporated immune murine splenocytes and HAT-sensitive murine myeloma cells was used. Cross-reactivity experiments confirmed that the MAb (MO6) does not bind to unrelated proteins such as bovine serum albumin, mouse IgG, and murine interferon-gamma (IFN-gamma). There are no effects when anti-IFN-gamma antibodies are used with MNSF. As far as biological activity is concerned, MO6 inhibits in vitro the activity of MNSF in terms of the Ig secretion from cultured lymphocytes. By using MO6, affinity chromatography and immunoblotting were performed. The MNSF on the SDS-PAGE showed a band with m.w. of approximately 70,000, indicating the formation of an aggregate in saline; but after treatment with 0.4 M pyridine-acetic acid buffer, separate bands of 24,000 and 16,000 daltons were evident. Therefore MO6 recognizes 70,000 and both 24,000 and 16,000 daltons. Thus we confirmed by using this MAb and affinity chromatography, the existence of human counterpart, human nonspecific suppressor factor (hNSF), in supernatant from concanavalin A-stimulated T cells. When hNSF was fractionated by high pressure liquid chromatography (HPLC), the activity was found in a region corresponding to 70,000 daltons. However, when fractionated in pyridine-acetic acid buffer, hNSF activity was distributed in a slightly wider range of 15,000 to 30,000 daltons. Physicochemical analysis showed that the purified hNSF is resistant to either heating at 56 degrees C or to 2-mercaptoethanol treatment; however, it is labile to acidification at pH 2.0 and is also sensitive to protease treatment, the characteristics of which were similar to those of murine MNSF. Thus MO6 was confirmed to be a pertinent tool for isolation of hNSF, as well as for murine MNSF.
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PMID:Characterization of monoclonal nonspecific suppressor factor (MNSF) with the use of a monoclonal antibody. 310

Two new human myeloma cell lines have been established from a 36-year-old woman with refractory IgG kappa multiple myeloma in whom bilateral malignant pleural effusions developed. The malignant plasma cells from each effusion were set up in a liquid culture using an L-15 medium containing catalase, glutathione, selenous acid, ascorbic acid, insulin, transferrin, additional glutamine hydrocortisone, and 2-mercaptoethanol and designated as M-3 medium. Two IgG kappa cell lines, LB -831 and LB-832, were established and proved to be Epstein-Barr virus negative using the internal repeat sequence DNA probe. Characteristic plasma cell morphology was evident by light and electron microscopy. Immunotyping revealed an IgG kappa , B1+, B2-, Ia (HLA-DR)+, CALLA+ phenotype for each cell line as well as for the original pleural fluid and bone marrow myeloma cells. The supernatants also contained IgG kappa, beta 2 microglobulin, and large amounts of osteoclast-activating factor (indicating bone-resorbing activity). Cytogenetic analysis of the LB-831 cell line revealed a nearly triploid highly abnormal karyotype with numerous clonal chromosomal abnormalities involving chromosomes 1, 3, 5, 7, 13, and 15; several structurally abnormal marker chromosomes; and a putative homogeneously staining region on chromosome 7p at band p22. Analysis of the LB-832 cell line revealed several additional clonal abnormalities. These additional cytogenetic changes suggest that in vivo sequential clonal evolution occurred in this patient. Therefore, two new but related cell lines have been established, which should prove useful for further biological studies.
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PMID:Establishment of two new myeloma cell lines from bilateral pleural effusions: evidence for sequential in vivo clonal change. 392 97

Cryostat sections of human central nervous system (CNS) tissue absorbed sheep erythrocytes (E) sensitized with rabbit IgG antibody (A). The indicator cells bound to the choroid plexus, to the leptomeninges covering the brain and spinal cord, to the arachnoid granulations and to the perivascular tissue of the neural parenchyma. Unsensitized E or E sensitized with F(ab')2 fragments of IgG were not bound. The reactions were inhibited by pooled human IgG, human IgG1 and IgG3 myeloma proteins, and Fc fragments of pooled human IgG. Whole human IgG2 myeloma protein, IgM, IgA, F(ab')2 fragments of pooled human IgG and albumin did not inhibit. Experiments with reduced and alkylated IgG, EDTA, iodoacetamide, 2-mercaptoethanol, various pHs and salt concentrations, formaldehyde, periodic acid and neuraminidase did not reveal any differences between the Fc gamma receptors in the separate anatomical areas. The Fc gamma receptors in human CNS are thus apparently very similar.
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PMID:Properties of Fc gamma receptors in the human central nervous system. 628

The production of hybridoma cell lines secreting antibody against foot-and-mouth disease virus (FMDV) was more difficult than the production of similar cell lines secreting antibody against vesicular stomatitis virus or measles virus. A rapid and efficient protocol for the selection and culturing of 'anti-FMDV' hybridoma cultures was therefore developed and is described. This required the determination of the optimal culture medium (commercially available), source of serum supplement, line of myeloma cells, type of culture and routine for the subculturing of the hybridoma cells. The protocol consisted of fusion between immune splenocytes and NS-1 mouse myeloma cells, seeding into the wells of 24-well (24W) plates, culturing in RMPI 1640 medium supplemented with either foetal or donor calf serum, and passaging through 24W plates, 6W plates and 100 ml flasks (20 ml medium), respectively. The time at which aminopterin was added to kill unfused myeloma cells was also critical, with the optimum time being 24 h after fusion. In contrast, the B lymphocyte growth stimulant (2-mercaptoethanol) had no beneficial effects on the growth of the hybridomas.
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PMID:Hybridoma cell lines secreting monoclonal antibodies against foot-and-mouth disease virus. 1. Cell culturing requirements. 630 48

Fc gamma receptor (FcR) from human placenta was solubilized using EDTA and 2-mercaptoethanol and purified by affinity chromatography on human IgG-coated Sepharose 4B. BALB/C mice were immunized with FcR and monoclonal antibodies were obtained by growing hybridoma cells following fusion of spleen cells with P3 X 63Ag8 myeloma cells. Using an immunofluorescence technique, the IgG1 monoclonal antibody secreted by clone B1D6 stained the FcR-positive areas in sections of placental tissue. The endothelium of the foetal stem vessels stained more strongly than did the trophoblasts. The antibody also inhibited the haemadsorption to placental tissue of erythrocytes (E) sensitized with IgG antibodies (A), (EA), and inhibited the agglutination of EA by FcR. The data indicate that the monoclonal antibody reacts with the placental FcR at the binding site for IgG, or with an epitope close to the binding site. Apparently, the FcR in different anatomical areas in the placenta have a common antigenic determinant.
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PMID:A monoclonal antibody inhibiting human placental Fc gamma-receptor activity. 638 62


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