Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Preferential enhancement of IgE antibody response was observed in BALF/c mice by the administration of Bordetella pertussis with antigen (DNP-Salmonella). Correlation between B cell mitogenic activity and adjuvant action among B. pertussis, Salmonella, lipopolysaccharide of Escherichia coli and Ficoll was examined but was not found. Thymus-derived cells seemed necessary to develop adjuvant action of B. pertussis since antibody response in athymic nude mice was not influenced by B. pertussis. Helper function of adoptively transfered spleen cells was enhanced by immunization of the donor mice with carrier antigen in the presence of B. pertussis. The magnitude of enhancement was greatest in IgE class. The results indicated that preferential enhancement of IgE antibody formation by B. pertussis is mediated by the augmentation of carrier-specific helper function.
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PMID:Preferential enhancement of IgE antibody formation by Bordetella pertussis. 19 43

The adjuvanticity of a phenotypic (C-mode) variant of B. pertussis, known to be deficient in certain immunological and physiopathological properties, was compared to that of the normal (X-mode) strain. The X-mode vaccine was a potent adjuvant for induction of hyperacute experimental allergic encephalomyelitis to guinea-pig spinal cord in Lewis rats whereas C-mode vaccine was inactive. X-mode vaccine was also highly active in the induction of reaginic (both IgE and IgGl) antibodies to ovalbumin in mice while C-mode vaccine caused only a transitory increase in the IgE level. These data support the view that an adjuvant component of B. pertussis, which is probably identical with the histamine-sensitizing and leukocytosis promoting factor, is much diminished in C-mode cells while the lipopolysaccharide adjuvant remains unchanged.
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PMID:Loss of adjuvanticity in rats for the hyperacute form of allergic encephalomyelitis and for reaginic antibody production in mice of a phenotypic variant of Bordetella pertussis. 50 Jan 13

The potentiation effect of various adjuvants on the production of guinea-pig IgE was investigated using Freund's complete and incomplete adjuvant, the lipopolysaccharide of Escherichia coli and Salmonella typhosa, Bordetella pertussis, and the nematodes Nippostrongylus brasiliensis and Ascaris suum. While all the antigens had a variable effect on the potential of the IgG response, only infection with A. suum resulted in an enhanced IgE response to the antigen, egg albumin. Maximum potentiation occurred when primary immunization and nematode infection were accomplished simultaneously.
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PMID:Effect of Ascaris suum and other adjuvants on the potentiation of the IgE response in guinea-pigs. 50 Jan 18

Lymphocytes from twenty-five patients with atopic dermatitis were investigated for their in vitro reactivity to stimulation with tuberculin (PPD), lipopolysaccharide (LPS), phytohaemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM). The response to a low dose of Con A was increased, and the reactivity in unstimulated cultures tended to be lower than similar cultures from the control group. Addition of inactivated autologous plasma to the cultures had an inhibitory effect, when the plasma came from patients with high levels of IgE. The patients' in vitro reactivity to PPD in a leucocyte migration test was equal to that found in normal persons and no effect was observed after addition of autologous serum. The mean percentage of E rosette forming cells was significantly reduced in patients with high levels of IgE. The number of EAC rosette forming cells was within normal range. It is hypothesized that the observations could reflect the existence of suppressor mechanisms in patients where the immune system is strongly stimulated.
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PMID:PPD and mitogen responsiveness of lymphocytes from patients with atopic dermatitis. 84 45

Heat-labile, rat skin-fixing antibodies were detected readily in the sera of young female mice dosed intranasally with the body fluid of Ascaris suum (ABF) and the adjuvant, Bordetella pertussis vaccine (BPV). In addition, washed cell suspensions prepared from spleen and the lymph nodes regional to the lungs were positive in an adoptive cutaneous anaphylaxis assay, an assay which may detect activities of reagins associated with mast cells rather than reaginic antibody-secreting cells. The intraperitoneal route was a poor means of inducing circulating anti-ABF reagins and an intraperitoneal injection of ABF + BPV delayed the appearance of circulating reagins in mice dosed at the same time with ABF + BPV intranasally. Hypothymic female BALB/c. nu/nu ('nude') mice failed to produce circulating reagins to ABF but an injection of normal thymocytes or cortisone-resistant thymocytes from syngeneic female mice led to higher titers of circulating reagins than found in normal female BALB/c. nu/+ littermates. Using cells from young male or female syngeneic donors and male and female BALB/c. nu/mu recpiients, evidence was obtained for a defect in the thymus of young male mice and conceivably this defect may extend to the peripheral T cell population in such mice. Cyclophosphamide pretreatment or adrenalectomy increased circulating reagin titers in normal mice dosed intranasally with ABF + BPV, and pretreatment with lipopolysaccharide intranasally markedly reduced titers of circulating anti-ABF reagins. In the discussion, emphasis is given to the hypothesis that potent allergens are T cell-stimulating, relatively persistent antigens which, when located in submucosal lymphoid sites and under conditions of limited antibody production as a result of limited recruitment of 'helper' T cells systemically, lead to the induction and sustained production of IgE by resident Bxi cells and their progeny.
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PMID:Studies on immune responses to parasite antigens in mice. II. Aspects of the T cell dependence of circulating reagin production to Ascaris suum antigens. 108 24

The effect of synthetic complexes of polyribocytidylic acid (poly-IC) on the production of homocytotropic antibodies by guinea-pigs was studied. It was observed that poly-IC has a definite adjuvant effect on the production of both IgG1 and IgE. The adjuvant effect was present when poly-IC was injected 24 hours after the antigen, but was absent when the polynucleotide was injected 48 hours after the antigen. In comparison with lipopolysaccharide (LPS) the adjuvant effect of poly-IC was weaker, more than 0.5 mg/kg of this polynucleotide being required to show an adjuvant effect, whereas only 20 mug/kg of LPS was enough to show a positive adjuvant effect. Furthermore, considerably less antibody was detected in the animals stimulated with the polynucleotide.
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PMID:The effect of a synthetic double-stranded RNA on IgC1 and IgE production by guinea-pigs. A comparative study with lipopolysaccharide. 115 87

Lymphokine directed isotype switching is preceded by the induced expression of the corresponding germline Ig heavy chain constant region (CH) gene. This association favors a model in which lymphokine induced germline CH gene expression promotes switch recombination by increasing the accessibility of the switch region to a recombinase(s). An important prediction of this model is that the induction of germline CH RNAs represents increased specific de novo transcription. To test if this prediction is fulfilled by the switch commitment factors, IL-4 and transforming growth factor-beta (TGF-beta), we have utilized a B cell line, 1.29, that switches from IgM to IgE and IgA in vitro. In this cell line, IL-4 and TGF-beta increase germline C epsilon and C alpha RNA levels respectively, predominantly by elevating transcription of these genes. Transcription of germline C epsilon and C alpha genes appears to be independently regulated and is not affected by lipopolysaccharide or IL-5. These results are discussed in the context of the molecular events necessary to commit a B cell to an isotype switch.
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PMID:Transcriptional regulation of the germline immunoglobulin C alpha and C epsilon genes: implications for commitment to an isotype switch. 136 52

T cell-dependent B cell activation and the induction of isotype switching require antigen and direct contact with helper T (Th) cells. During activation, B cells can switch from the expression of IgM to that of IgG, IgE or IgA, depending on the lymphokines secreted by the Th cell with which they interact. Studies of lipopolysaccharide (LPS)-activated B cells have suggested that lymphokines regulate isotype switching via a transcriptional mechanism that increases the accessibility of downstream CH genes to a switch recombinase(s). To assess the roles of T cell contact and lymphokines in isotype switching, we have examined the accessibility model for the regulation of isotype switching to IgG1 in the context of cognate interactions between Th cells and normal B cells. We demonstrate that Th2 cells that secrete IL-4 can induce expression of germline gamma 1 transcripts in B cells. The steady-state level of germline gamma 1 transcripts induced by Th2 cells is enhanced as compared with the level induced by IL-4 alone or Il-4 and LPS also alters the relative usage of the germline gamma 1 transcription initiation sites. Enhanced expression of germline gamma 1 transcripts requires direct contact between T and B cells suggesting a role for T cell contact-mediated signals in regulating the accessibility of switch regions.
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PMID:IL-4-induced expression of germline gamma 1 transcripts in B cells following cognate interactions with T helper cells. 137 44

The switch of activated B cells to IgE synthesis is an interleukin (IL)-3-dependent process. It is currently thought that specific T cells activated by antigen presented in the context of class II major histocompatibility complex are the major source of IL-4. Recently it has been demonstrated that a splenic non-T non-B cell population (termed NBNT) has the capacity to produce IL-4 following IgE and IgG receptor cross-linkage. In this study we demonstrate that IL-4 producing NBNT cells can induce the switch of lipopolysaccharide-activated B cells to the synthesis of IgG1 and IgE antibodies. Furthermore, it was found that not only IgE receptor cross-linkage but IL-3 was able to stimulate NBNT cells to produce IL-4 and induce the switch of B cells to IgE synthesis. NBNT cells derived from the spleen and bone marrow of SCID mice were able to produce IL-4 on exposure to IL-3. This suggested that the ability of IL-3 to stimulate IL-4 production was not dependent on prior exposure of the NBNT cells to antibody complexes in vivo. Taken together these findings represent the first observation that enough IL-4 is produced by NBNT cells to actually influence a B cell IgG/Ig response. The findings also clearly demonstrate that B cells do not need high concentrations of IL-4 to be directed to switch to IgG1 and IgE synthesis.
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PMID:Interleukin-3-treated non-B, non-T cells switch activated B cells to IgG1/IgE synthesis. 142 6

Although interferon (IFN)-gamma has been shown to be involved in the down-regulation of polyclonal IgE response in murine B cells that were activated by lipopolysaccharide (LPS) and interleukin 4 (IL4), effects of IFN-gamma on antigen-specific IgE responses have not been fully investigated. We have developed the following culture systems for inducing antigen-specific IgE responses in murine lymphocytes, and examined the effects of IFN-gamma on the following responses in vitro. (1) Anti-trinitrophenyl (TNP) IgE response induced by the stimulation with TNP-keyhole limpet hemocyanin (KLH) of BALB/c spleen cells that had been primed in vivo with the same antigen. (2) Anti-TNP IgE response induced by the coculture of unprimed C3H B cells with conalbumin (CA)-specific helper T cell clone, D10.G4.1, in the presence of TNP-CA. The former anti-TNP IgE response was not suppressed, and the latter suppressed only partially (less than 30%) by the addition of 100-200 U/ml IFN-gamma. In contrast, polyclonal IgE response in murine B cells that were stimulated by LPS and IL4 was abolished by 10 U/ml IFN-gamma. These results indicate that IgE production from antigen-stimulated B cells, in contrast to those activated polyclonally, are refractory to direct suppression by IFN-gamma.
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PMID:In vitro antigen-specific IgE response is refractory to suppression by interferon-gamma. 148 4


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