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)

Seven Epstein--Barr virus (EBV)-transformed B cell lines were derived from circulating lymphocytes of two atopic and two non-atopic individuals, two preparations of cord blood lymphocytes and one tonsillar lymphocyte preparation. All the cell lines contained a significant proportion of cells expressing Fc epsilon R as detected by rosette formation with IgE-coated bovine erythrocytes (E-IgE) and by flow cytometry using IgE-linked to fluorescent microspheres. None of the cell lines displayed FcR for IgA, IgM or IgG. The cell-free supernatants (CFS) of EBV-transformed cells contained IgE-binding factors (IgE-BFs) detected by their ability to inhibit the binding to RPMI 8866 cells of either E-IgE or IgE-linked to microspheres. Whereas these CFS enhanced the synthesis of IgE and suppressed the synthesis of IgG by purified B lymphocytes isolated from the blood of allergic donors and cultured in the absence of stimulant, their effect on the synthesis of IgA or IgM was not predictable. CFS significantly enhanced the secretion of IgE by the U266 myeloma cell line without interfering with secretion of IgM, IgG or IgA by EBV-transformed cells. These data are in accord with similar properties of RPMI 8866 cells and suggest that B lymphocytes might play a regulating role in the IgE synthesis.
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PMID:In vitro synthesis of IgE by human lymphocytes. III. IgE-potentiating activity of culture supernatants from Epstein-Barr virus (EBV) transformed B cells. 609 68

Mouse monoclonal antibodies to various human epidermal and basement membrane components were formed by immunizing Balb/c mice with ME-180, a line of human cervical carcinoma cells. The spleen cells from hyperimmunized mice were fused with a nonsecreting mouse myeloma cell line using polyethylene glycol. The resulting hybrids were selected by growth in media containing 20% fetal calf serum, hypoxanthine, thymidine, and methotrexate in RPMI-1640 in 24-well Linbro plates. Wells producing antibodies of interest were grown and eventually cloned over an HGPRT- rat fibroblast feeder layer. These cultures were expanded and recloned. Two cloned antibodies of interest are DUX 5.2 and DUX 1.1.3. DUX 5.2 is the mouse IgG1 subclass and reacts with the membranes of ME-180 cells and the human skin epidermal basement membrane zone as shown by direct immunofluorescent microscopy. Ultrastructural localization using electron microscopic immunoperoxidase techniques showed localization of the DUX 5.2 antigen to be beneath the lamina densa; the reaction product may include the anchoring fibrils. Although DUX 5.2 reacts with the normal human basement membrane zone and the basement membrane zone in several diseases, there is no reactivity in the normal, never-blistered skin of patients with dystrophic epidermolysis bullosa (DEB). This suggests that the increased collagenase in the disease may be destroying antigenicity of the antigen recognized by DUX 5.2 or that the antigen may not be present in DEB. This antibody will thus allow early neonatal and prenatal diagnosis in DEB and allow isolation of the structural moiety which is deficient in DEB. DUX 1.1 is an IgM mouse immunoglobulin specific for the cytoplasm of human basal cells. Its reactivity with upper epidermis is significantly less than that seen in the basal layer. All cells of the basal layer stain uniformly. The slight amount of staining in upper cells probably represents dilution of antigen which is not synthesized beyond the basal layer. Basal cells of hair follicles and sweat glands are stained to some degree.
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PMID:Monoclonal antibodies to normal and abnormal epithelial antigens. 619 49

T-lymphocyte subpopulations were studied in 68 patients with monoclonal gammopathies and 27 age-matched healthy controls using the monoclonal antibodies (mAb) OKT-3, OKT-4 and OKT-8. 13 patients had untreated multiple myeloma (MM), 51 had MM and were receiving intermittent pulse chemotherapy or were in remission and followed up without treatment. Four patients had a monoclonal gammopathy of unknown significance (MGUS). Analysis of the data for disease activity demonstrated a significant imbalance of T-lymphocyte subpopulations in patients with stable (plateau phase) MM. In these patients the relative number of cells with suppressor phenotype (OKT-8 positive) was significantly increased (p less than 0.0001) and the relative number of cells with helper phenotype (OKT-4 positive) significantly decreased (p less than 0.0001) when compared with normal controls or patients with active MM. Patients with stable disease also had a significantly higher absolute number of OKT-8 positive cells than patients with active MM (p = 0.04). Additionally, in vitro functional studies showed significant suppression of clonal growth of the human myeloma cell line (RPMI 8226) by a soluble suppressor factor of OKT-8 positive cells from the peripheral blood of healthy donors as well as from bone marrow aspirates of patients with MM. These findings support the hypothesis that T-lymphocyte subpopulations play an important role in the control of proliferation of the myeloma cell clone in patients with low cell mass (stable phase) multiple myeloma.
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PMID:[OKT-8+ suppressor T-lymphocytes are increased in patients with stable multiple myeloma]. 622 89

It was previously shown that RPMI 8866 cells released IgE-binding factors (IgE-BFs) capable of enhancing the spontaneous in vitro synthesis of IgE by purified B lymphocytes isolated from allergic individuals. In the present study, the influence of tunicamycin, an inhibitor of protein glycosylation, on RPMI 8866 cells was investigated with regard to: (i) the expression of surface receptors for IgE; (ii) the release of IgE-BFs into the culture supernatants, and (iii) the biological activity of IgE-BFs. After preincubation for 60 min with tunicamycin (1 microgram/ml), RPMI 8866 cells were cultured for 48 hr in HB 101 serum-free medium; the culture supernatant was then filtered, concentrated, and its biological activity was compared to that of a parallel culture supernatant from untreated RPMI 8866 cells. The results of these experiments indicate that exposure of RPMI 8866 cells to tunicamycin resulted in: (i) a reduction of surface Fc epsilon R; (ii) no effect on the release of IgE-BFs into the culture supernatant, and (iii) the conversion of IgE-potentiating factors into IgE-suppressing factors. The latter factors suppressed the IgE secretion by U266 myeloma cells and completely inhibited the activity of IgE-potentiating factors on B lymphocytes from allergic individuals. IgE-BFs secreted by tunicamycin-treated cells had no effect on the production of IgG, IgA or IgM by normal or EBV-transformed B cells.
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PMID:In vitro synthesis of IgE by human lymphocytes. IV. Suppression of the spontaneous IgE synthesis by IgE-binding factors secreted by tunicamycin-treated RPMI 8866 cells. 623 5

A retrovirus designated RPMI 8226V, isolated in 1973 from the human myeloma cell line RPMI 8226 has been characterized by competition radioimmunoassay (RIA) for the major viral structural protein and by nucleic acid hybridization analysis using cDNA of the virus. The virus is highly related to the squirrel monkey type D retrovirus, SMRV. In the homologous RIA using rabbit anti-RPMI 8226V and 125I-labelled p37 of RPMI 8226V, RPMI 8226V and SMRV exhibited competition of 81% and 73% respectively. Similarly, in the homologous system for SMRV p36, these viruses competed 98 and 100%. Reagents made from the type D retrovirus. Mason Pfizer Monkey Virus (MPMV), known to be related but distinct from SMRV, were used in assays designed to detect interspecies determinants of type D retroviruses. In assays using goat anti-MPMVp26 vs SMRV 125I-p36, RPMI 8226V, SMRV and MPMV competed to the same extent (93%). Hybridization analysis of RPMI 8226V cDNA showed significant homology to cellular RNA and DNA of mink, bat, and human cell infected with RPMI 8226V and to DNA or SMRV infected cells but not to uninfected cells or cells infected with other viruses. These results taken together clearly indicate that RPMI 8226V and SMRV are very closely related to each other. The finding of a type D retrovirus in this human myeloma cell line that had been used in EBV studies (the usual source of EBV being the marmoset cell line B95-8) prompted a survey of RPMI 8226V in some human and marmoset cell lines. The assays included the RIA for p36, nucleic acid hybridization using cDNA of RPMI 8226V, reverse transcriptase analysis and electron microscopy (EM). The results clearly show that in addition to RPMI 8226, human Burkitt lymphoma cells BJAB/B-95-8/K which were supertransformed by EBV from B-95-8/K marmoset cells as well as marmoset cell lines [(B-95-8/K and B-95-8/N) obtained from Stockholm and Uppsala, Sweden] were positive for the RPMI 8226V. Similar lines obtained elsewhere were negative. The results obtained clearly indicate that RPMI 8226V is a serious laboratory contamination in some widely used human cell lines. The possible impact of this viral contamination for some virological and cell biological studies is discussed.
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PMID:Identification of the RPMI 8226 retrovirus and its dissemination as a significant contaminant of some widely used human and marmoset cell lines. 628 81

A monoclonal antibody which recognizes the [125I]human GH ([125I]hGH)-binding proteins of rabbit liver has been produced using hybridoma technology. A CB6F1/J mouse was immunized over a period of 82 days with a partially purified GH receptor (GHr) preparation. On the 83rd day, spleen cells from the mouse were fused with P3x20 mouse myeloma cells using polyethylene glycol 1540. Hydridomas were produced by selection in hypoxanthine, aminopterin, and thymidine in RPMI/1640 medium and screened for antibody production using a binding inhibition assay. Four antibody-secreting clones were isolated from the same primary well, and one of these was injected ip into mice to generate ascitic fluid. At a concentration of 1:10,000, the ascitic fluid inhibited 50% of the specific binding of [125I]hGH to rabbit liver GHr, and at higher concentrations, the ascitic fluid was capable of inhibiting 95% of the specific binding. The ascitic fluid does not bind [125I]hGH nor does it inhibit [125I]hGH binding to rat liver membranes, rabbit mammary gland, or IM9 lymphocytes. More than 90% of the antibody activity was abolished by goat antimouse immunoglobulin G antiserum. An immunoglobulin fraction from the ascitic fluid, precipitated by ammonium sulfate and coupled to activated CH Sepharose, specifically adsorbed an [125I]hGH binding moiety from Triton X-100-solubilized rabbit liver membranes. After dissociation by brief exposure to 0.1 M glycine (pH 2.0), the moiety retained hGH-binding activity. Preliminary experiments indicate that the antibody will be helpful in purification of the rabbit liver GH receptor.
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PMID:A monoclonal antibody to the growth hormone receptor of rabbit liver membranes. 630 60

Of several human fusion partners available for the production of monoclonal antibodies, only SKO-007 and RPMI 8226 have phenotypic features characteristic for myeloma cells. Cells from both lines exhibited abundant rough endoplasmic reticulum (RER) with a prominent Golgi apparatus, few free ribosomes, condensed nuclear chromatin, and absence of the Epstein-Barr virus determined nuclear antigen (EBNA). However, following prolonged passage of these lines, the amount of immunoglobulin (Ig) production has declined. The other cell lines, GM 1500 6TG-A11, KR-4, B6, HS-Sultan, and Raji possessed the phenotypic characteristics of B-lymphoblastoid cell lines (LCLs) and B-lymphomas including surface Ig expression, sparse RER, free polyribosomes, a poorly developed Golgi apparatus and strong EBNA expression. Accordingly, they secreted little (nanograms) or no Ig. However, hybrids constructed with two LCLs secrete very large amounts of Ig despite their expressed morphologic similarity to the parental lines. These data indicate that morphology can still be used as an important consideration in choosing a human fusion partner but other parameters such as fusion frequency, cloning efficiencies, and growth rates may be equally important.
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PMID:A comparative analysis of the phenotypic characteristics of available fusion partners for the construction of human hybridomas. 633 55

A new monoclonal antibody specific for human B cell differentiation antigen (HLB-1) is produced by a hybridoma established by fusion of splenocytes of mice immunized with the Epstein-Barr virus (EBV)-transformed peripheral B cell line, RPMI-8057. This monoclonal, antibody designated anti-HLB-1 monoclonal antibody (anti-HLB-1), reacted with surface immunoglobulin (sIg)-positive B cells of normal peripheral blood and lymphoid tissues and sIg-positive leukemic cells. The cells of T cell leukemia, non-T non-B acute lymphoblastic leukemia (ALL) and nonlymphoid leukemia were HLB-1 negative. These data were further confirmed by studying a panel of cultured human hematopoietic cell lines. Anti-HLB-1 reacted with B cell lines derived from pre-B, Burkitt's lymphoma, B cell type ALL and EBV-transformed peripheral B cells. Anti-HLB-1 was reactive with only one of three human myeloma cell lines, and with none of the T cell, myeloid and non-T non-B ALL cell lines. This newly defined HLB-1 antigen is different from other conventional human B cell markers such as sIg, Ia antigens, and receptors for the Fc portion of Ig and complement C3.
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PMID:A monoclonal antibody defining human B cell differentiation antigen (HLB-1 antigen). 640 55

Monoclonal antibodies to deoxycorticosterone were produced. Mice were immunised with deoxycorticosterone-3-mono-oxime-BSA conjugate and spleen cells were then hybridised with NS1/1Ag4-1 mouse myeloma cells using 1500 mol. wt polyethylene glycol. The hybrids were grown in RPMI 1640 medium containing HAT to facilitate selection of positive clones. The clones and subclones were screened by using deoxycorticosterone-3-mono-oxime-[125I]iodohistamine. Dextran-coated charcoal was used for separation of antibody bound and free fractions. Two independent clones producing antibody which specifically binds labelled deoxycorticosterone were obtained. Cells from the two best sub-clones were used to raise ascites fluid. Comparison of these antibodies with one of the best conventional antisera previously raised in rabbits showed that the affinity constants were almost comparable (0.49-1.4 X 10(10) l/mol). Cross-reactivity of monoclonal antibodies with cortisol, corticosterone, testosterone and pregnenolone was lower than for polyclonal antisera, but for progesterone the cross-reactivity was similar in both cases. The assay sensitivity obtained with ascites fluid was comparable to that of conventional antibody (2.5 pg/ml). The dilution of ascites fluid which produced 50% binding of the label was 1:4,000,000. These results confirm that it is possible to produce monoclonal antibodies to corticosteroids.
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PMID:Production of high affinity monoclonal antibodies to deoxycorticosterone. 670 56

A stable line of IgG K producing human plasma cells was established from a myelomatous human bone marrow using conditioned media from a rapidly metabolizing lymphoblast line, RPMI 4098. Growth in RPMI 1640 (15% fetal calf serum) at 6% CO2 promoted a 62-hour doubling time with a preferred cell concentration of 1 x 10(6)/mL. Surface marker studies showed: no receptors for sheep erythrocytes, no surface immunoglobulins, variable number of cells bearing complement receptors and 83% bearing Fc receptors. Although transmission electron micrographs demonstrated a poorly developed endoplasmic reticulum, radioimmunoassay showed 23 ng IgG and 28.7 ng Kappa were produced by 1 x 10(6) cells in 72 hours. Further, the cells are lipase, esterase and Epstein-Barr nuclear antigen negative. ASG banding showed a total chromosome number that varied from 46--49. Since the number of human plasma cell lines is limited, it is felt that this line will augment the immunobiological study of human myeloma.
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PMID:A human plasma cell line: induction and characterization. 680 81


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