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)

We have investigated the ability of an antisense oligonucleotide (ASE-1) to specifically inhibit IgE synthesis by a human myeloma cell line, U266. ASE-1 inhibited IgE production in a concentration-dependent manner, as assessed by isotype-specific ELISA measurement of immunoglobulin in myeloma cell supernatants. Inhibition of IgE production was specific and not due to cytotoxicity since IgG1 and IgM production by human myeloma cell lines ARH-77 and RPMI-1788 respectively, was not significantly affected by up to 20 microM ASE-1 whereas IgE production was inhibited by approximately 70% at this concentration. These results indicate that antisense oligonucleotides represent a potential therapeutic approach to the treatment of IgE-mediated allergic diseases.
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PMID:Specific inhibition of IgE antibody production by an antisense oligodeoxynucleotide oligomer (Oligostick). 147 91

A system of exon "modules" was produced from the functionally rearranged epsilon-heavy gene isolated from the rat IgE-secreting immunocytoma IR162. The five individual exons, encoding the variable and constant region domains, were isolated and subcloned into the multiple cloning site of a pair of plasmid vectors with opposed orientation multiple cloning sites. The use of opposed orientation multiple cloning sites and the flanking restriction enzyme sites contained therein allows for the modular manipulation of the gene. These exon modules were initially used to reconstruct the epsilon-heavy chain gene into the native configuration to demonstrate the efficacy of the modular system for synthesis of IgE. Upon transfection into the rat myeloma cell line Y3, the reconstructed gene produced a polypeptide that associated with the endogenous light chain polypeptide and was secreted from the cell as tetrameric IgE. All physical and functional characterizations indicate that the IgE molecule produced is indistinguishable from native IR162 IgE. This modular system of exons will facilitate the manipulation of IgE structure through the systematic assembly of different epsilon-heavy chain mutant constructions. The resulting novel IgE proteins will be very useful to study the molecular nature of the interaction of IgE with its Fc receptor.
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PMID:The expression and characterization of rat IgE produced by construction of the epsilon-heavy chain gene from exon modules. 153 68

As a first step toward defining the molecular interactions between ligands and the IgE antigen-combining site, we report here the cDNA cloning and variable (V) region nucleic acid sequences of the heavy (H) and light (L) chains of 2 monoclonal mouse IgE antibodies to trinitrophenyl (ATCC-TIB142 = IGELa2 and ATCC-TIB141 = IGELb4). In all instances, full-length cDNA clones were obtained to facilitate future expression studies. The H chains were encoded by VH genes from the VH3660 and J558 gene families in context with DQ52 and DSP2.2 diversity (D) mini genes, and JH3 and JH4 joining (J) gene segments, respectively. Vk8/Jk2 and Vk1/Jk5 rearrangements encoded the respective L chain V-regions. Both antibodies exhibited considerable conservation of complementarity determining region (CDR) sequences, which will facilitate template-based computer modeling of the three-dimensional structures of complexes formed between various ligands and these antibodies. From sequence comparison between the dinitrophenyl (DNP)-binding myeloma protein MOPC-315 and these IgE antibodies likely candidates for hapten-contact residues within the binding sites of IGELa2 and IGELb4 have been suggested.
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PMID:Mechanism of allergic cross-reactions--III. cDNA cloning and variable-region sequence analysis of two IgE antibodies specific for trinitrophenyl. 154 95

The human T cell hybridoma AC5 has been shown to produce an IgE-binding factor (IgEBF) upon stimulation with T cell mitogens, or anti-CD3 antibody. In this study, the line was established, propagated long term in a newly available serum-free, protein-free medium, and the factor it produced was analyzed. Serologic analysis, utilizing an ELISA assay and biotin-labeled human Ig of various isotypes, revealed that the IgEBF thus obtained was highly specific for the Ig epsilon-chain and was released primarily within the first 24 h after mitogen stimulation. Using biotin-labeled IgE as the detecting reagent, Western blot analysis of this factor demonstrated that the molecule was a single chain moiety of m.w. 64,000, and could be purified to apparent homogeneity by either DEAE or affinity (IgE column) chromatography. Detection of the IgEBF by ELISA and Western blot correlated well with activity in the previously employed rosette inhibition assay. Finally, purified IgEBF was found to suppress in vitro the production of IgE in the monoclonal human myeloma line U266, but not IgA or IgM-producing myelomas, providing evidence for the direct and specific regulatory action of this molecule on IgE-producing cells.
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PMID:Serologic, biologic and western blot analysis of human IgE-binding factor derived from a T cell hybridoma maintained in protein-free medium. 157 71

Certain species of histamine-releasing factor (HRF) have been demonstrated to distinguish a select group of allergic patients from healthy subjects. An IgE-dependent mechanism of action has been suggested. The donor and IgE dependency of HRF produced by peripheral blood mononuclear cells (PBMCs) has not been clearly demonstrated. In this study, we have compared the response of basophils from normal subjects versus allergic patients with and without asthma. In addition, we have addressed the IgE dependency of HRF recovered from cultures of PBMCs, T cells, B cells, macrophages, and bronchoalveolar lavage fluid. We have demonstrated that basophils from allergic as well as normal subjects respond to PBMC-HRF. The response of basophils from allergic patients with asthma is significantly increased. This heightened response to HRF does not correlate with the severity of disease as assessed by baseline spirometry, medication, and skin test scores. Stripping of the membrane-bound IgE by incubating basophils with lactic acid causes a significant loss of sensitivity to HRF generated by PBMCs, T cells, B cells, and macrophages, as well as to HRF recovered from bronchoalveolar fluid. The loss of response can be restored by sera from patients with asthma but not from normal subjects or by myeloma IgE. In addition, poorly responsive basophils from normal subjects can be rendered sensitive by incubating with sera from patients with asthma. The capacity of a given serum from a patient with asthma to restore the response to HRF is not correlated with the total concentration of IgE in the serum.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sensitivity of basophils to histamine releasing factor(s) of various origin: dependency on allergic phenotype of the donor and surface-bound IgE. 169 33

Sensory neuropeptides, such as substance P, appear as potent mediators of various immunological reactions, and inhibit or stimulate a wide range of functions of immune inflammatory cells. Platelets were recently shown to participate as effector cells in an IgE or lymphokine-dependent killing of parasites. Substance P and its carboxy-terminal fragment SP (4-11) induce the cytotoxic activity of platelets towards the larvae of Schistosoma mansoni, respectively, by 90% and 40%, whereas the modified C terminal SP, the SP-free acid, exhibits no effect on the platelets. The neuropeptide effects occur at low doses (10(-8) M), are specific as shown by inhibition studies with a substance P antagonist, the D-SP. Binding data obtained after flow cytofluorometry with FITC-SP lead to the conclusion that SP binds specifically to about 20% of the homogenous population of platelets. Moreover, IgE could modulate the SP-dependent functions of platelets since the pre-incubation with myeloma human IgE or with AP2 monoclonal antibodies--known to inhibit the IgE-dependent killing of these cells-leads to a dramatic decrease of the SP dependent cytotoxic activity of platelets towards the larvae. These findings identify a potent mechanism for nervous system regulation of host defence responses.
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PMID:The neuropeptide substance P stimulates the effector functions of platelets. 169 68

Peptostreptococcus magnus strain 312 (10(6) to 10(8)/ml), which synthesizes a protein capable of binding to kappa L chains of human Ig (protein L), stimulated the release of histamine from human basophils in vitro. P. magnus strain 644, which does not synthesize protein L, did not induce histamine secretion. Soluble protein L (3 x 10(-2) to 3 micrograms/ml) induced histamine release from human basophils. The characteristics of the release reaction were similar to those of rabbit IgG anti-Fc fragment of human IgE (anti-IgE): it was Ca2(+)- and temperature-dependent, optimal release occurring at 37 degrees C in the presence of 1.0 mM extracellular Ca2+. There was an excellent correlation (r = 0.82; p less than 0.001) between the maximal percent histamine release induced by protein L and that induced by anti-IgE, as well as between protein L and protein A from Staphylococcus aureus (r = 0.52; p less than 0.01). Preincubation of basophils with either protein L or anti-IgE resulted in complete cross-desensitization to a subsequent challenge with the heterologous stimulus. IgE purified from myeloma patients PS and PP (lambda-chains) blocked anti-IgE-induced histamine release but failed to block the histamine releasing activity of protein L. In contrast, IgE purified from myeloma patient ADZ (kappa-chains) blocked both anti-IgE- and protein L-induced releases, whereas human polyclonal IgG selectively blocked protein L-induced secretion. Protein L acted as a complete secretagogue, i.e., it activated basophils to release sulfidopeptide leukotriene C4 as well as histamine. Protein L (10(-1) to 3 micrograms/ml) also induced the release of preformed (histamine) and de novo synthesized mediators (leukotriene C4 and/or PGD2) from mast cells isolated from lung parenchyma and skin tissues. Intradermal injections of protein L (0.01 to 10 micrograms/ml) in nonallergic subjects caused a dose-dependent wheal-and-flare reaction. Protein L activates human basophils and mast cells in vitro and in vivo presumably by interacting with kappa L chains of the IgE isotype.
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PMID:Protein L. A bacterial Ig-binding protein that activates human basophils and mast cells. 169 70

Because of the lack of a cell line expressing on surface and secreting human IgE of known Ag specificity, the construction of a transfectoma line possessing such properties would be useful for studying the roles of surface IgE and the effects of anti-IgE antibodies on IgE-producing B cells. Toward this goal, the human genomic DNA segment encompassing the two exons encoding the membrane anchor peptide of epsilon-chain and their flanking regions was sequenced. Hybrid epsilon and kappa genomic DNA comprising the C regions of human epsilon- and kappa-chains and the H and L chain V regions of the murine mAb BAT123, which reacts with the gp120 envelope protein of HIV-1, were constructed. Mammalian expression vectors containing these fusion genes were used to transfect murine myeloma Sp2/0 cells, and transfectants stably expressing on surface and secreting into culture medium chimeric IgE were obtained. The chimeric IgE showed identical Ag-binding properties as the murine mAb BAT123. Acting in concert with the specific peptide Ag polyvalently coupled to a protein carrier, the chimeric antibody could induce histamine release from human blood basophils. These results demonstrate the potential utility of the transfectoma cells and the chimeric IgE in studying the roles of membrane-bound IgE and effects of anti-IgE antibodies on IgE-producing B cells.
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PMID:Transfectomas expressing both secreted and membrane-bound forms of chimeric IgE with anti-viral specificity. 170 91

Basophil responsiveness to histamine-releasing factors (HRF) is limited to cells from atopic donors; this response can be transferred passively to non-reactive basophils by IgE molecules from the sera of donors who are intrinsically responsive to HRF. Deuterium oxide (D2O) also causes mediator release from the basophils of atopic asthmatic subjects. To assess whether basophil responsiveness is IgE dependent, and, if so, whether this release revealed IgE heterogeneity, we tested the ability of sera from HRF responders (IgE+) and non-responders (IgE-) to sensitize basophils to D2O. Both purified IgE+ and unpurified sera from an HRF responder were passively used to sensitize basophils whose IgE had been removed by lactic acid treatment. As a control, an IgE- myeloma-containing serum was used for passive sensitization. In five experiments, histamine release in the presence of 44% D2O was 9 +/- 2% and 46 +/- 4% using control IgE- and IgE+ sensitized cells, respectively. The non-responder serum, even at higher IgE levels, did not sensitize the cells for D2O release. If the IgE receptors on lactic-acid treated cells were first exposed to serum from an IgE- donor, sensitization to D2O by IgE+ was blocked. The percentage histamine release to D2O was directly related to both the amount of IgE+ used for passive sensitization and the concentration of D2O used for release. These experiments further support the concept of IgE heterogeneity and suggest that the occupancy of IgE receptors on the basophil surface 'activate' the cell to make it more responsive to various stimuli.
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PMID:The heterogeneity of human IgE exemplified by the passive transfer of D2O sensitivity. 170 90

Twelve monoclonal antibodies (mAb) were isolated that bound to six clusters of epitopes on the constant region of the epsilon chain of human IgE. Four of the mAb bound to the C epsilon 1 or early C epsilon 2 regions; three of these bound to the IgE myeloma protein PS and to serum IgE but not to the IgE myeloma protein ND. These mAb probably recognize an allotypic marker. Another mAb reacted with heat-denatured, but not native IgE. Four of the mAb failed to release histamine; the epitopes recognized by these mAb are in the C epsilon 1, C epsilon 2 and C epsilon 3-4 regions of IgE. Three of these non-histamine releasing mAb did not bind to IgE on the basophil surface. These mAb recognize epitopes in C epsilon 2 and C epsilon 3-4 that are not accessible when IgE is bound to its receptor. Four mAb inhibited IgE binding to basophils; two of these did not release histamine, and two others that bind to epitopes in the C epsilon 2-4 domain, released histamine and therefore blocked IgE binding by steric hindrance. Inhibition of IgE binding by different mAb suggest that the Fc epsilon RI and Fc epsilon RII bind to partly overlapping regions of the IgE molecule although the sites do not appear to be identical. A number of sites on C epsilon 1 and C epsilon 3-4 were accessible when IgE is bound to its basophil receptor. The data support the concept that only part of the Fc portion of IgE is hidden in the receptor and that portions of C epsilon 1-4 are accessible on the cell surface. These mAb should be useful in determining the domains of IgE that are critical for its biological activity.
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PMID:Monoclonal antibodies defining epitopes on human IgE. 171 47


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