Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the accompanying report, we have compared a B cell-specific protein mitogen, Salmonella thyphimurium mitogen (STM), to lipopolysaccharide (LPS), dextran sulfate (DxS), and the combination of LPS/DxS with regard to their ability to induce B cell proliferation and differentiation. The results of these studies demonstrated that STM, LPS, and LPS/DxS induce significant expression of cytoplasmic immunoglobulin (Ig). In this report, we have analyzed the distribution of isotypes induced by each of these mitogens in the presence or absence of interleukin-4 (IL-4) containing T cell supernatants (SN), since IL-4 increases the secretion of IgG1 and IgE and decreases the secretion of IgG3 and IgG2b in LPS-stimulated splenic B cells. These experiments were designed to determine whether LPS was unique in its ability to "program" B cells to respond to IL-4 by secreting IgG1, as has been suggested in our previous studies. The current experiments also addressed the issue of whether splenic B cells were unique in their response to IL-4 by using B cells from other tissues. The efficiency of induction of cytoplasmic Ig measured in the preceding report was STM greater than LPS/DxS greater than LPS. DxS did not induce a significant level of cell proliferation, cytoplasmic Ig, or secreted IgM and inhibited the LPS-induced IgM response by approximately 50%. In contrast, STM induced an extremely high level of IgM secretion in splenic B cells. In this report, we demonstrate that the addition of IL-4-containing T cell SN to splenic B cells stimulated with LPS, LPS/DxS or STM increased the level of IgG1 and reduced the level of IgM, IgG3, and IgG2b secretion.(ABSTRACT TRUNCATED AT 250 WORDS)
J Mol Cell Immunol 1987
PMID:Activation of murine B cells from different tissues with different mitogens. II. Isotype distribution of secreted immunoglobulins in the presence and absence of IL-4-containing T cell supernatants. 350 24

The immunogenicity of a novel hapten, the anti-microbial agent, chlorhexidine (1,1'-hexamethylene bis [5-(p-chlorophenyl)biguanide]) was assessed in mice, using alum as adjuvant. The i.p. injection of electrostatically-linked chlorhexidine + keyhole limpet haemocyanin (KLH) mixtures induced low level primary IgG anti-chlorhexidine antibody synthesis. In contrast, covalently-linked chlorhexidine-KLH complexes induced both IgE and IgG anti-chlorhexidine antibody synthesis. Covalent binding was facilitated by the N-chlorination of secondary amide groups on the biguanide moeities of the chlorhexidine molecule. The immunogenicity of such complexes was related to the degree of conjugation of chlorhexidine to KLH; which, in turn, was related to the molarity of chlorine used to effect N-chlorination. Immune responses to covalently-linked complexes could be enhanced by carrier priming. The induction of low levels of IgG anti-hapten antibodies by electrostatically-linked complexes may reflect T cell-independent specific B cell activation, either by chlorhexidine itself or by a "pseudo-plurivalent" chlorhexidine + KLH antigen.
Mol Immunol 1987 Feb
PMID:Factors influencing the immunogenicity of the haptenic drug chlorhexidine in mice--Part I. Molecular requirements for the induction of IgE and IgG anti-hapten antibodies. 361 8

The thermally induced changes in human IgE was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When the IgE (1 mg/ml) was heated at 56 degrees C for several hours in the absence of sodium dodecyl sulfate, it gave aggregated forms that could be reduced completely to heavy and light chains with dithiothreitol. On the other hand, in the presence of sodium dodecyl sulfate (0.1%), the IgE was changed by heating to five components with small mol. wts dependent on temperature and pH. This phenomenon was observed also in mouse monoclonal IgG1, but the degree of change was considerably lower than that of human IgE. The five components obtained from the heat-treated IgE (LHHL) were identified as LHHL, HL, H, LL and L. These results show that the thermally induced changes in human IgE are dependent on the exchange of its intra- and inter-disulfide bonds.
Mol Immunol 1987 Mar
PMID:Thermally induced disulfide bond exchanges in human IgE. 361 14

The influence of purified human immunoglobulins on the migration of human neutrophils (PMN) was measured in a 48-well micro chemotaxis chamber, with results expressed as percentages of maximal formyl-methionyl-leucyl-phenylalanine (FMLP)-stimulated chemotaxis. Both monomeric and polymeric IgA, of both subclasses, in monoclonal and polyclonal form, as well as secretory IgA and Fc-alpha, but not Fab-alpha fragments, enhanced PMN migration when present either in the lower or in both compartments of the chamber (chemokinesis) at concns as low as 0.1 mg/ml. IgM and IgE had no such effect. In contrast, IgG was chemotactic at low concn (0.1 mg/ml). Both monomeric and polymeric IgA decreased the maximally induced FMLP-chemotaxis, but IgA increased chemotaxis induced by suboptimal levels of FMLP. Binding of 3[H]-FMLP to PMN was not affected. Cytofluorographic analysis revealed that, under the conditions of the assay, IgA did bind to 93% of PMN. Thus, the various forms of IgA have a dual effect on human PMN mobility: (1) increase PMN random migration (chemokinesis); and (2) decrease the maximal FMLP-induced chemotaxis. Our data support the requirement of binding of IgA to the Fc-alpha receptor of PMN for expression of these activities. This effect of IgA on PMN mobility may be relevant in IgA deficiency states.
Mol Immunol 1987 Jun
PMID:IgA-induced chemokinesis of human polymorphonuclear neutrophils: requirement of their Fc-alpha receptor. 365 95

A human IgE Fc epsilon fragment was isolated from the supernatant of the culture fluid of a recombinant mouse L cell line, L-IS11IgE-9. The purification procedure consisted of salting out from the supernatant with ammonium sulfate, immunoaffinity chromatography on a monoclonal antibody (E235I63)-Affi Gel 10 column, and gel filtration chromatography on a Sephacryl S-200 column. The final preparation represented a 5825-fold purification from the original culture fluid with a 25% recovery and about 3.1 mg of Fc epsilon fragment was obtained from 201 of culture fluid. The sp. act. of the purified preparation measured by the use of commercial human IgE determination kits was 0.93 x 10(6) units/mg protein. The purified preparation was homogeneous as judged by the end group analyses. The amino acid composition of the preparation coincided with that deduced from DNA sequence. The mol. wt of our preparation was about 110,000 under non-reducing conditions and 55,000 under reducing conditions on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These results showed that our preparation was a dimeric form having high reactivity against anti-human IgE antibodies.
Mol Immunol 1987 Oct
PMID:Purification and characterization of recombinant human IgE Fc epsilon fragment produced in mouse L cells. 368 1

Human IgE was isolated for the first time from the supernatant of the culture fluid of a human myeloma cell line, U266. The purification procedure consisted of salting out from the supernatant with ammonium sulfate, affinity chromatography on a lysine-Sepharose 4B column, ion exchange chromatography on a DEAE-Sephacel column, gel filtration and recycling chromatography on a Sephacryl S-300 column and removal of bovine proteins on an anti-bovine serum rabbit IgG-Sepharose 4B column. One hundred and twenty eight milligrams of IgE was recovered from 461 of culture fluid. The purification was extremely simplified by the introduction of immunoaffinity chromatography using the monoclonal antibody prepared by immunizing a mouse with an IgE preparation obtained by the above method: about 3.3 mg was recovered from 960 ml of culture fluid. The purified preparation was homogeneous as judged by the double-immunodiffusion test and end group analysis. The amino acid and carbohydrate compositions of the preparation coincided with those reported on other preparations obtained from the sera of myeloma patients. Our preparation, however, showed two bands with apparent mol. wts of 240,000 and 230,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis. When it was reduced with dithiothreitol and analyzed by electrophoresis, it gave two heavy chains and one light chain with apparent mol. wts of 80,000 and 76,000, and 28,000, respectively. On the other hand, the IgE molecule that was synthesized and secreted into the medium in the presence of tunicamycin (0.5 microgram/ml) gave only one heavy chain and one light chain with apparent mol. wts of 62,000 and 28,000, respectively. These results demonstrated that the two IgE molecular species contained in our preparation differed from each other in the carbohydrate moiety in their heavy chains.
Mol Immunol 1986 Feb
PMID:Purification and characterization of IgE produced by human myeloma cell line, U266. 370 74

Two peptides, P123 and P124, representing amino acid sequences His 542-Lys 557 and Tyr 459-Arg 472, respectively, of the CH4 domain of rat IgE and predicted to be located on accessible regions of the protein were synthesized by a solid-phase procedure. Rabbits were immunized with the peptides conjugated to KLH and their antisera were tested for reactivity with free peptide and rat IgE by inhibition-ELISA. Each animal produced antibodies which reacted specifically with its immunizing peptide (titre greater than 1/62,500), but not with other synthetic peptides of similar chain-length and composition. Antisera directed against peptides P123 and P124 specifically bound purified rat IgE (IR 162) and IgE in whole myeloma serum (greater than 1/6400), but showed no reaction with normal rat serum proteins and only very low binding to purified human IgE. In addition the binding of anti-peptide sera to rat IgE could be completely inhibited with either homologous peptide or purified rat IgE, but not by other peptides or purified human IgE. Heating rat IgE for 1 hr at 56 degrees C enhanced its binding to anti-peptide antibodies by between 4- and 60-fold, but markedly reduced its reactivity with a rabbit anti-rat IgE (Fc) serum. These results suggest that antibodies directed against the synthetic peptides employed recognize and specifically bind to sites within the CH4 domain of rat IgE represented by their respective immunizing peptides. Furthermore, these antibodies are capable of detecting subtle alterations in structural conformation resulting from heating at 56 degrees C. Epitopes represented by peptides P123 and P124 may contribute to the heat-sensitive cytophilic region of rat IgE.
Mol Immunol 1986 Feb
PMID:Use of synthetic peptides in the production and characterization of antibodies directed against predetermined specificities in rat immunoglobulin E. 370 75

A model of the Fc of human IgE was constructed using the known three-dimensional structure of IgG Fc. On the basis of amino acid sequence homology, the CE2, CE3 and CE4 domains were modelled after CG3, CG2 and CG3, respectively. The mode of association of the CG2 and of the CG3 pairs of domains was assumed for the CE3 and the CE4 pairs, respectively; the CE2 pair of domains was assembled such that they interact like the CG3 domains. An asymmetric linkage is favored for the two inter-epsilon chain disulfide bridges, i.e. the bonds were assumed to be between non-homologous cysteines. The atomic interactions in the interface of the CE2:CE2 and CE4:CE4 domain pairs were computed, and predictions are made on the solvent accessibility of the individual residues in the fragment. The model can be useful in the study of regions that may be involved in the interaction of IgE with Fc(epsilon) receptors.
Mol Immunol 1986 Oct
PMID:A model of the Fc of immunoglobulin E. 379 18

A switch variant of the I.29 murine B-cell lymphoma expressing membrane IgE and inducible by lipopolysaccharide (LPS) to increase the rate of IgE secretion was characterized. The cells (I.29 epsilon +2) express membrane-bound IgE, and also secrete considerable amounts of IgE when grown in regular culture medium. Membrane and secreted IgE contain structurally different heavy chains. The former is constituted by a 93-kd molecule (epsilon m), while secretory chains (epsilon s) have an apparent mol. wt of 86,000. Both epsilon m and epsilon s are heavily glycosylated: in the presence of tunicamycin their apparent mol. wt is reduced by approx. 35% (61 kd for epsilon m and 56 kd for epsilon s). Glycosylation is necessary for membrane expression and for secretion of IgE molecules. Stimulation with LPS leads to the disappearance of IgE molecules from the cell surface (determined by radioiodination) although epsilon m-chains are still synthesized, suggesting a defective transport of membrane IgE in LPS-treated cells. The epsilon m:epsilon s ratio decreases upon LPS stimulation. A similar change can be observed in the messenger RNAs specific for epsilon m and epsilon s, possibly suggesting a major pretranslational control for epsilon m and epsilon s biosynthesis.
Mol Immunol 1985 Nov
PMID:Biosynthesis of membrane and secreted epsilon-chains during lipopolysaccharide-induced differentiation of an IgE+ murine B-lymphoma. 393 17

Two monoclonal antibodies of the IgE class (54.10) and of the IgG1 class (27.21), that were shown previously to possess biological activity against Schistosoma mansoni larvae, were used for identification of surface antigens of the cercariae and schistosomula. This was performed by immunoprecipitation, immunoaffinity chromatography and immunoblotting. The epitope reactive with 27.21 mcIgG1 is present on four polypeptides (60, 50, 27 and 19 kDa) derived from the parasite. The 60 kDa is specific to cercariae, whereas the 50 kDa is a glycoprotein shared both by cercariae and schistosomula. The antigen reactive with the 54.10 mcIgE was isolated by affinity chromatography on 54.10 column, and contained three major peptides of 125, 94 and 30 kDa. The 125 and 94 kDa band probably originate from the same protein, since they yield almost identical peptide maps. The isolated antigen retained its biological activity as demonstrated in the basophils degranulation assay.
Mol Biochem Parasitol 1985 May
PMID:Identification of Schistosoma mansoni antigens by means of biologically active monoclonal antibodies. 401 Jul 3


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