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)

The influence of zinc on the in vitro antibody response to antigen or mitogen stimulation was studied by adding various concentrations of ZnCl2 to cultures of spleen cells stimulated with sheep erythrocytes, trinitrophenyl-lipopolysaccharide or with the polyclonal B cell activator E. coli lipopolysaccharide (LPS). Addition of ZnCl2 in concentrations ranging from 10(-8) or 10(-7) to 10(-5) M increased the specific antibody response to antigens or the polyclonal antibody synthesis induced by stimulation with LPS, when the response of the assayed population in the control cultures without ZnCl2 was low, as observed in cultures without 2-mercaptoethanol (2-ME). However, in cultures supplemented with 2-ME, the potentiating effect of ZnCl2 diminished or disappeared or even the antibody response was inhibited. Higher concentrations of ZnCl2 markedly depressed (5 X 10(-5) M) or abolished (10(-4)) the in vitro induced antibody response in all cultures. The various mechanisms which could mediate the effects of zinc are discussed.
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PMID:Modulation by zinc of the in vitro antibody response to T-dependent and T-independent antigens. 660 99

Recent studies in guinea pigs indicated that active vaccination with a cell wall-derived, lipopolysaccharide (LPS) pseudomonas vaccine confers specific protection against acute pneumonia. This study analyzed the immune mechanisms by which LPS pseudomonas vaccine offers local protection to the lung. Neither parenteral vaccination nor direct exposure of lung tissues to living Pseudomonas activated alveolar macrophages. However, serum opsonic activity that specifically enhanced phagocytosis of Pseudomonas by alveolar macrophages was significantly increased (P < 0.05) in vaccinated animals. Serum pseudomonas opsonins were heat-stable but were sensitive to reduction of macroglobulins by 2-mercaptoethanol. Within 3 hr after establishment of experimental pseudomonas pneumonia, a fourfold increase in local pseudomonas opsonins was found in bronchial fluids from vaccinated animals, presumably secondary to diffusion of serum proteins into local inflammatory fluids. Thus, Pseudomonas-specific opsonic antibody appears necessary to augment alveolar macrophage phagocytosis after LPS vaccination, and local vaccination of the respiratory tract is not required to provide adequate local pseudomonas opsonins during acute pneumonia.
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PMID:Mechanism for pulmonary protection by lipopolysaccharide pseudomonas vaccine. 677 32

The serum antibody response in BALB/c mice to a lipopolysaccharide-protein (LPS-P) complex was monitored by the enzyme-linked immunosorbent assay, total and 2-mercaptoethanol-resistant hemagglutination, and radial immunodiffusion. Dose-response analyses demonstrated that suitable primary doses of LPS-P injected IV or IM induced substantial concentrautions of specific serum immunoglobulin (Ig) M and IgG. Moreover, these values were greatly enhanced with small-dose booster injections. Inoculation of mice with a suitable primary IM dose of aluminum hydroxide-precipitated LPS-P-induced specific IgM and IgG amounts that were detectable for 120 days. An enhanced secondary response to antigen booster injections was generated 105 days after primary inoculation, providing direct evidence that LPS-P can induce immunologic memory. Similar results were obtained for IV inoculations of LPS-P, although the primary IgG response was not as persistent. Seemingly, the memory response to LPS-P was largely dependent on the protein component of the molecule.
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PMID:Induction of immunologic memory by a lipopolysaccharide-protein complex isolated from Fusobacterium necrophorum: humoral response. 680 41

The study of 270 serum samples obtained from chronic brucellosis patients in the passive hemagglutination test have revealed that in the presence of specific brucellosis hemagglutinins cross reactions with Yersinia antigen may occur. This phenomenon is probably due to the presence of common antigenic determinants in the lipopolysaccharide fractions of Brucella abortus 99 and Yersinia enterocollitica 09. The passive hemagglutination test has revealed that 2-mercaptoethanol-sensitive antibodies (IgM) to both homologous and heterologous antigens are mainly present in chronic brucellosis patients.
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PMID:[Importance of cross reactions in evaluating the serological diagnosis of human brucellosis. II. Examination of brucellosis patients by the passive hemagglutination reaction using homologous and heterologous erythrocyte diagnostica]. 681 29

Staphylococcal peptidoglycan (PG) is a B cell mitogen and immunomodulator in mice. The ability of PG to induce the secretion of polyclonal antibodies in murine lymphocyte cultures was studied using the protein A hemolytic plaque assay. PG was as effective as or more effective than lipopolysaccharide as an inducer of polyclonal antibodies in spleen, lymph node, and bone marrow lymphocytes. The highest numbers of immunoglobulin (Ig) secreting cells were induced in the spleen, and the lowest in the bone marrow cell cultures. All major classes of Ig (IgM, IgG, and IgA) were induced, and the maximal numbers of Ig-secreting cells were detected between days 4 and 5 of culture. The induction of Ig secretion by Pg was T cell, 2-mercaptoethanol, and to a large extent macrophage independent.
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PMID:Polyclonal activation of immunoglobulin secretion in B lymphocytes induced by staphylococcal peptidoglycan. 696 84

Seven thiol compounds, namely, 2-mercaptoethanol (2-ME), alpha -thioglycerol (alpha -TG), dithiothreitol (DTT), cysteamine, L-cysteine (Cys), glutathione (GSH), and sodium thioglycollate (TGL) were examined for their mitogenic activities, the effects on mitogen-induced 3H-thymidine uptake, and the effects on antibody synthesis in vitro in murine spleen lymphocytes. All these thiols showed mitogenic activities in RPMI-1640 medium containing 10% fetal calf serum (FCS) with the following order of effectiveness: 2-ME greater than or equal to alpha -TG greater than DTT greater than cysteamine greater than Cys greater than or equal to GSH greater than TGL. A close correlation was observed between the enhancement of the response to lipopolysaccharide (LPS) and the mitogenic activities of these thiol compounds in their magnitude and dose-response profiles. The primary antibody response in vitro to sheep red blood cells (SRBC) (thymus-dependent) or dinitrophenyl (DNP)-Ficoll (thymus-independent) was augmented in a similar fashion by these compounds. T-cells depletion did not influence the enhancement by 2-ME of the antibody response to DNP-Ficoll. There was a discrepancy between the dose-response profiles of mitogenic activities of these compounds and their augmenting effects on antibody responses. Particularly, 2-ME and DTT significantly enhanced the antibody response to DNP-Ficoll or SRBC even at the nonmitogenic doses. Ethyl mercaptan (HSCH2 CH3) showed similar activities to 2-ME, but methylthioethanol (CH3 SCH2 CH2 OH) and ethanol (CH3 CH2 OH) were inactive, thus indicating that the thiol group would play an essential role in the above activities of 2-ME.
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PMID:Activation of murine lymphocytes by 2-mercaptoethanol and related thiol compounds and its mechanism. I. Relationship between mitogenic activities and augmenting effects on antibody synthesis in vitro. 697 54

We investigated the ability of various polyclonal B-cell activators (PBA) to induce immunoglobulin synthesis, circulating immune complexes, and rheumatoid-factor-like autoantibodies. We found that, following the injection of a PBA--bacterial lipopolysaccharide, dextran sulfate, polyriboinosinic-polyribocytidilic acid, or purified protein derivative of tubercle bacteria--a transitory formation of circulating immune complexes occurred simultaneously with an increase in immunoglobulin production. The presence of circulating immune complexes after PBA administration was documented by the 125I-Clq-binding assay and the conglutinin-binding assay, and a partial characterization of this material was achieved. Although the kinetic properties, size, and composition of the immune complexes tested varied with the PBA used, the complexes detected in each group were inactivated by mild reduction and alkylation with 2-mercaptoethanol and were unaffected by DNase treatment. In the mice injected with bacterial lipopolysaccharide, the induction of circulating immune complexes correlated significantly with the presence of rheumatoid-factor-like antibodies, suggesting that this autoantibody may be present within the detected immune complexes. In tissues, glomerular deposits of IgM, IgG, and C3 were observed in a pattern compatible with the deposition of immune complexes. These deposits were progressively associated with marked glomerular abnormalities in mice chronically injected with LPS during 1 year. These data suggest that the induction of polyclonal antibody synthesis, which occurs in a variety of infectious or autoimmune diseases, may be responsible for the high incidence and persistence of immune complexes in these diseases. Such complexes would involve primarily autoantigens and corresponding autoantibodies, such as rheumatoid factor IgG complexes, without the participation of any specific bacterial, viral, or parasitic antigen.
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PMID:Induction of circulating immune complexes and their renal localization after acute or chronic polyclonal B-cell activation in mice. 698 26

The differential effect of 2-mercaptoethanol (2-ME) on spleen and bone marrow cells of young and old mice was determined in vitro. Both the ability of spleen cells to proliferate and to generate Ig-secreting cells and the capacity of bone marrow cells to generate myeloid colonies were assessed. All three activities assessed in both young and old mice were enhanced by the presence of 2-ME, but a differential effect with respect to age was noted in only one. This was the polyclonal activating antibody response to bacterial lipopolysaccharide (LPS) in which 2-ME enhanced young spleen cells to a greater extent than old spleen cells, although their mitogenic responses to LPS were enhanced to the same extent. The ability of 2-ME to enhance old spleen B cells to proliferate but not differentiate in their response to LPS would suggest that aging alters certain subpopulations of spleen cells, some of which are sensitive and others insensitive to the potentiation effects of 2-ME. The enhancing action of 2-ME on the proliferative activity of LPS-stimulated young spleen cells was reduced drastically by decreasing the number of T cells by prior treatment of spleen cells with anti-T cell reagent. The proliferative activity was then brought back to normal pretreatment level by adding enriched T cells. Therefore it would appear that regulatory T cells are the target of the enhancing action of 2-ME. The failure of old spleen cells to respond vigorously to the polyclonal activating action of LPS and 2-ME individually and in combination would indicate that age-related alterations may be taking place in the B cells and/or the regulatory cells. Young-old spleen cell mixture study indicates that there are regulatory cells in old spleen cells which can inhibit B cell differentiation but not B cell proliferation.
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PMID:Restoration of impaired immune functions in aging animals. VI. Differential potentiating effect of 2-mercaptoethanol on young and old murine spleen cells. 698 45

The mechanism of augmentation of the primary antibody response in vitro by 2-mercaptoethanol (2-ME) was investigated. By using cystine-free RPMI 1640 medium, it was demonstrated that cyst(e)ine was absolutely required for eliciting the following murine lymphocyte reactions: antibody response to sheep erythrocytes, proliferative response to concanavalin A or lipopolysaccharide (LPS), and polyclonal antibody response induced by LPS. The maximal antibody response was attained with 2.5-5 mM cysteine or half-cystine. The serial feeding of fresh cysteine markedly amplified its capacity to support antibody response particularly when cysteine concentration was suboptimal. Such an effect was not observed in the serial addition of cystine. On the other hand, the dose-response curve of cystine was dramatically shifted to lower concentrations by the addition of 2-ME (1 x 10(-5) M), which alone could not elicit the antibody response in the absence of cystine, nor could it augment furthermore the maximal response induced by 2.5 mM half-cystine. Commercially available RPMI 1640 medium contains 0.41 mM half-cystine, which proved to be a suboptimal concentration for eliciting the maximal response. 35S-cystine was incorporated into murine lymphocytes five to six times more slowly than 35S-cysteine. The rate of cystine uptake, however, was accelerated by 2.5-fold in the presence of 1 x 10(-5) M 2-ME. A close correlation was observed between dose-response profiles of 2-ME in augmenting the antibody response and the stimulation of cystine uptake. These results strongly suggest that one of the roles of 2-ME in augmenting the antibody response in vitro is to facilitate the use of cystine contained in RPMI 1640 medium only at a suboptimal concentration.
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PMID:Mechanism of augmentation of the antibody response in vitro by 2-mercaptoethanol in murine lymphocytes. I. 2-Mercaptoethanol-induced stimulation of the uptake of cystine, an essential amino acid. 704 May 90

A broad spectrum of agents known to block various steps in the lipid peroxidation process were tested for their ability to protect mouse spleen cells and thereby enhance their activities, in vitro, in either the primary antibody response or the lipopolysaccharide-stimulated proliferation response. Each agent (superoxide dismutase, butylated hydroxyanisole/butylated hydroxytoluene/n-propyl gallate, lucigenin, and alpha-tocopherol) was able to enhance the cellular response in both assay systems. The degree of enhancement of these immune functions was in proportion to the efficacy of each agent in blocking the overall process in lipid peroxidation. Previous work in this laboratory has shown that the enhancement of the primary antibody response by 2-mercaptoethanol (2-ME) is mediated by the enhanced availability of reduced glutathione in the culture medium. Suboptimal doses of each lipid antioxidant agent were able to enhance the antibody response in the additive manner with a suboptimal dose of 2-ME up to a maximum response equal to that achieved with an optimal dose of 2-ME alone. These data support the hypothesis that the enhancement of cellular responses in the presence of 2-ME is mediated by the lipid antioxidant activity of reduced glutathione.
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PMID:Agents which block membrane lipid peroxidation enhance mouse spleen cell immune activities in vitro: relationship to the enhancing activity of 2-mercaptoethanol. 726 79


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