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 receptor for IgE (Fc epsilon RII) on human eosinophils presents some common characteristics with CD23, a differentiation marker of B cells. We have used flow cytometry for evaluating the expression of various epitopes of CD23 on purified eosinophils from patients with eosinophilia. A correlation was found between the binding of myeloma IgE protein and the binding of a monoclonal antibody (mAb 135), directed against the IgE-binding site of B cell CD23. Using two additional anti-CD23 mAb, directed (8-30) or not (3-5) against the IgE-binding site, a low expression of these CD23 epitopes was observed on eosinophils from different eosinophilic patients. Northern blot analysis of eosinophil RNA with the cDNA probe of CD23 revealed a low-abundance transcript in three of the six patients expressing membrane CD23. The inhibition by all anti-CD23 mAb of IgE-mediated cytotoxicity and IgE binding to eosinophils clearly indicated the participation of a CD23-related molecule in IgE-dependent eosinophil functions.
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PMID:Heterogeneous expression of CD23 epitopes by eosinophils from patients. Relationships with IgE-mediated functions. 171 83

Circulating histamine-releasing factors have been identified in the serum and plasma of chronic-urticaria patients by in vivo skin testing and in vitro histamine release from heterologous mixed leukocytes. Quantitative mast cell studies of serum skin test biopsies and electron microscopy indicate that the serum factors release histamine by mast cell degranulation. Peripheral blood basophils and total cellular blood histamine are reduced in chronic-urticaria patients suggesting that the circulating serum factors cause sustained degranulation. Histamine-releasing activity has been identified by skin testing in ultrafiltered serum fractions less than 30 kDa and greater than 100 kDa. In vitro histamine-releasing activity was confined to ultrafiltered serum fractions greater than 100 kDa and was present in IgG purified from some chronic-urticaria sera by protein G affinity chromatography. The dose-response relationship and kinetics of histamine release in vitro were similar to those of anti-human IgE. 'Desensitisation' of basophils by prior incubation with anti-IgE in the absence of calcium and competitive inhibition studies with myeloma IgE serum indicated that histamine-releasing autoantibodies in chronic-urticaria sera and purified IgG have the properties of anti-IgE. Plasma exchange in 4 patients with active chronic urticaria refractory to antihistamine therapy showing in vivo and in vitro histamine-releasing activity was followed by temporary remission of disease activity in 2 of them. It is possible that chronic urticaria is an autoimmune disease.
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PMID:Histamine-releasing autoantibodies in chronic urticaria. 172 16

Circulating histamine releasing factor(s) have been demonstrated previously in chronic urticaria by an immediate weal-and-flare response to intradermal autologous serum injection. We have studied 25 chronic urticaria patients by in vivo skin testing with autologous sera and an in vitro histamine release assay using mixed leukocytes of healthy donors, to define the nature and functional properties of the serum factor(s). Twenty showed a weal response to autologous serum (mean +/- s.e.m., 37.3 +/- 6.8 mm3). Weal formation was confined to ultrafiltered serum fractions greater than 100 kD in nine of nine patients. There was no response in 10 healthy controls of five patients with symptomatic dermographism. Fourteen chronic urticaria sera elicited histamine release greater than 10% (mean +/- s.e.m., 44.3% +/- 6.7) above basal levels from leukocytes of at least one of seven healthy donors. This in vitro response was also confined to ultrafiltered serum fractions greater than 100 kD in seven of seven sera and was present in IgG fractions of six of seven chronic urticaria sera that showed histamine releasing activity. Functional studies indicated that this histamine releasing autoantibody had the properties of anti-IgE: chronic urticaria sera 'desensitized' basophil leukocytes to subsequent challenge with other chronic urticaria sera and to goat anti-human IgE antibody; human myeloma IgE inhibited histamine release from leukocytes in response to chronic urticaria sera; removal of surface-bound IgE by lactic acid 'stripping' reduced histamine release in response to chronic urticaria sera and anti-IgE and subsequent passive sensitization with IgE myeloma serum partially restored it. Stainable peripheral blood basophils/mm3 in chronic urticaria patients were significantly reduced (mean +/- s.e.m, 7.9 +/- 2.0) when compared to healthy controls (39.6 +/- 4.4), P less than 0.001. These results suggest that histamine releasing autoantibodies are important in the pathogenesis of chronic urticaria by stimulating or facilitating degranulation of basophils and cutaneous mast cells through cross-linking cell surface IgE receptors.
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PMID:Detection of circulating histamine releasing autoantibodies with functional properties of anti-IgE in chronic urticaria. 172 43

An IgE-binding factor(s) (IgE-BF(s] was partially purified from the supernatant of human HTLV-II carrying T-cell line MO. This IgE-BF(s) was shown to increase the IgE synthesis in the human myeloma cell line U-266, but did not affect its viability or growth. The effect of the IgE-BF(s) was dose-dependent and selective for IgE protein synthesis as beta 2-microglobulin synthesis in the U-266 and the immunoglobulin production in the U-1958 IgG-secreting human myeloma cell line were unaffected. The IgE-BF(s) increased the production of the epsilon heavy chain but not the lambda light chain production. The IgE-BF(s) was distinct from IL-1 beta, IL-3, IL-4, IL-5, IL-6, TNF-alpha, IFN-alpha, -beta, -gamma, M-CSF, and fragments of CD23.
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PMID:Enhancement of IgE synthesis in the human myeloma cell line U-266 with an IgE binding factor from a human T-cell line. 174 21

IgE antibodies are best known for their pathological role in allergy. The class-specific effector sites are located in the epsilon chains; these form covalent dimers via two cystine residues (Cys241 and Cys328) linking opposite C epsilon 2 domains. The nature and biological significance of the inter-epsilon chain disulfide-bond arrangement is unresolved. For structural and functional analysis site-specific mutations were introduced into the C epsilon 2 domain of recombinant human IgE. The introduction of an additional cyanogen bromide cleavage site (His246----Met) facilitated the identification of parallel disulfide bond pairing. This linkage was also confirmed for myeloma IgE PS by sequence determination of disulfide-linked C epsilon 2 dimers. Substitution of Cys241 and Cys328 by Ser does not destroy receptor binding, but reductive alkylation, or the replacement of Cys328 by Met, leads to loss of activity. This shows that covalent dimerization is not essential for IgE/receptor interaction and points to the importance of the structural integrity of the site surrounding Cys328, visualized in a new model of human Fc epsilon.
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PMID:The nature and importance of the inter-epsilon chain disulfide bonds in human IgE. 182 28

Skin biopsies of 31 non-atopic patients, 20 with mycosis fungoides, six with psoriasis and five with contact dermatitis, and of five non-atopic healthy controls were compared for the presence of cell-bound IgE and vacant IgE binding sites. IgE+ cells were demonstrated in the cutaneous infiltrate of nine (45%) patients with mycosis fungoides, two (33%) with psoriasis and one (20%) with contact dermatitis. Following pre-incubation of skin sections with IgE myeloma protein to saturate vacant IgE-binding sites, 14 out of 16 patients (88%) with stage I mycosis fungoides, five (83%) patients with psoriasis and one (20%) with contact dermatitis showed an increase in the number of IgE+ cells. While cell-bound IgE was positively related to serum IgE levels the expression of IgE-binding sites was not. All IgE+ cells were HLA-DR+ dendritic cells identified as either macrophages (CD68+, CD14+) or Langerhans cells (CD1+). Skin biopsies of non-atopic healthy controls or clinically uninvolved skin in mycosis fungoides had neither any IgE+ cells nor any vacant binding sites. Inhibition studies with IgG1, IgG4 and IgE myeloma proteins as well as with several enzymatic fragments of IgE demonstrated that IgE interacted with Fc epsilon-receptors through isotype-specific structures on the Fc epsilon-fragment. Four anti-CD23 monoclonal antibodies, however, were unable to stain vacant Fc epsilon-receptors nor could they block IgE-binding. We hypothesize that locally-secreted lymphokines, like IL-4 or interferon-gamma, induce Fc epsilon-receptors on dendritic cells in the cutaneous infiltrate and that these receptors become occupied in parallel with elevated serum IgE levels.
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PMID:Cell-bound IgE and increased expression of Fc epsilon-receptors on dendritic cells in cutaneous infiltrates of mycosis fungoides. 183 78

The anti-IgE autoantibody was detected, using a radioimmunoassay, in 17 out of 35 (48.6%) of patients with atopic dermatitis. Significant increased levels of IgG-anti-IgE were seen in the patients studied compared with the control group. The specificity of the anti-IgE autoantibody was confirmed by competitive inhibition assay using IgG, IgM, IgE myeloma. A correlation was observed between the levels of IgG-anti-IgE and serum IgE but not between the IgG subclasses with anti-IgE activity and the clinical status. These data demonstrate that the IgG subclass distribution with anti-IgE activity belongs mostly to the IgG1 and IgG4 subclasses compared with the controls. Moreover, ultracentrifugation analysis indicated that the IgG-anti-IgE in the serum samples from the patients with atopic dermatitis was present in the form of an immune complex with self-IgE. These observations may suggest that the anti-IgE complexes may play a broader role in the modulation of the immune response and that this autoantibody may mask recognition of IgE in conventional assays.
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PMID:Evidence for IgE immune complexes and distribution of IgG subclasses with anti-IgE activity in patients with atopic dermatitis. 191 72

Human recombinant interleukin-3 (rIL-3; 10 U/ml) consistently augmented spontaneous IgE synthesis by isolated atopic B cells in vitro, whereas rIL-4 (1-1,000 U/ml) failed to induce IgE synthesis by these cells. Recombinant interferon-gamma (rIFN-gamma) suppressed ongoing IgE production by atopic B cells in a dose-dependent manner. IFN-gamma also inhibited IgE synthesis by a human myeloma cell line (U-266), demonstrating the direct effect of IFN-gamma on the terminal differentiation of IgE-secreting plasma cells. IL-3 and IFN-gamma from different sources displayed the same effects on IgE synthesis. Neutralizing antibodies toward IL-3 or IFN-gamma abolished their activities toward IgE synthesis, supporting the specificity of the effect of these cytokines. The quantity of endogenous IFN-gamma produced by stimulated T cells was significantly decreased in atopic patients compared to nonatopic controls, which might be responsible for the propensity of a high blood IgE level in atopic patients.
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PMID:Ongoing IgE synthesis by atopic B cells is enhanced by interleukin-3 and suppressed directly by interferon-gamma in vitro. 191 9

IgE is highly glycosylated, but the function of the oligosaccharide side chains is largely unknown. The previous discovery of an animal lectin, IgE-binding protein (epsilon BP), affords an opportunity to study potential carbohydrate-dependent effector functions of IgE. epsilon BP is a beta-galactoside-specific lectin with binding affinity for IgE and is now known to be equivalent to carbohydrate-binding protein 35 and the Mac-2 Ag; thus, it may have multiple functions in addition to IgE binding. We have previously shown that rat r epsilon BP recognizes sialidase-treated human myeloma IgE to a much greater extent than the untreated IgE. In contrast, human epsilon BP binds essentially equivalently to a monoclonal murine IgE with or without sialidase pretreatment. To validate a possible role for epsilon BP in the IgE system, we investigated the pattern of recognition of epsilon BP for various polyclonal human IgE samples. We show that polyclonal IgE derived from four individuals with hyper-IgE syndrome or atopic dermatitis recognizes epsilon BP and that there is individual variation in the proportion of IgE recognized by epsilon BP, ranging from greater than 60% for one sample to almost undetectable levels in another. We conclude that epsilon BP does indeed recognize polyclonal IgE and that this recognition is modulated by sialylation of IgE oligosaccharides. Furthermore, there exist different IgE glycoforms, varying in the degree of sialylation, and these are distributed in a distinct manner in different individuals.
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PMID:Heterogeneous IgE glycoforms characterized by differential recognition of an endogenous lectin (IgE-binding protein). 191 4

A new case of IgE myeloma is described. A 77-year-old woman presented with bone pain and fatigue. Serum protein analysis revealed a paraprotein of the IgE kappa type; bone marrow aspirate and immunofluorescence confirmed the diagnosis; ultrastructural examination showed immature plasma cells. Treatment with prednisone, melphalan, cyclophosphamide and interferon alfa did not produce any improvement and the patient died 5 months after diagnosis. The patient's clinical and laboratory data are compared with those of IgE myeloma cases reported in the literature.
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PMID:A new case of IgE myeloma. 201 30


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