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)

Prolonged dietary exposure of mice to the trichothecene vomitoxin induces abnormally high levels of serum IgA and kidney mesangial IgA accumulation in a manner that is highly analogous to the human glomerulonephritis IgA nephropathy. In this study, the capacity of Peyer's patch and splenic lymphocytes to produce IgA and IgG were compared in B6C3F1 mice that were fed diets with and without 25 ppm vomitoxin for up to 12 wk. Serum IgA increased 2-, 4- and 8-fold after 4, 8 and 12 wk, respectively, of vomitoxin exposure and it became the primary serum isotype, whereas serum IgG was unaffected. On termination of the experiment there were increased numbers of IgA-secreting cells in Peyer's patches after 8 wk of toxin exposure and in the spleen after 4, 8 and 12 wk of toxin exposure. There were also increased numbers of IgG-secreting cells in Peyer's patches on termination of the experiment at 4, 8 and 12 wk but no effects was observed in the spleen. Supernatant IgA and IgA-secreting cell numbers were also markedly elevated in lymphocyte cultures obtained from Peyer's patches and, to a lesser extent, from spleens of treated mice compared with controls. Based on output of treated mice relative to corresponding controls, IgA secretion was greatest in concanavalin-A-stimulated and unstimulated Peyer's patch cultures. Enhanced IgG secretion and IgG-secreting cells were also observed in mitogen-stimulated and unstimulated Peyer's patch lymphocyte cultures of treated relative to control mice, but differences in splenocyte cultures were negligible. Based on total Ig output, IgA production was 8- to 20-fold greater than IgG production in both control and treatment Peyer's patch cultures. In contrast, vomitoxin treatment caused a shift from primarily IgG production in lipopolysaccharide-stimulated spleen cultures to equivalent IgA production. These data provide in vitro evidence that ingestion of vomitoxin promotes terminal differentiation of IgA-secreting progenitors in the Peyer's patch and, to a lesser extent, in the spleen. These functional changes are consistent with the shift from IgG to IgA as the primary serum isotype.
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PMID:Effect of dietary administration of the trichothecene vomitoxin (deoxynivalenol) on IgA and IgG secretion by Peyer's patch and splenic lymphocytes. 227 98

Plasmid p5F which directs the expression of the Escherichia coli heat-labile enterotoxin B subunit (LT-B) from the ptac promoter was introduced into the attenuated Yersinia enterocolitica O:8 aroA mutant strain YAM.1. YAM.1 (p5F) expressed high levels of cell-associated and secreted LT-B in a stable fashion when grown on normal laboratory medium. The strain was used as a live oral vaccine in BALB/c mice and vaccinated mice developed high levels of gut-associated and systemic antibodies to both LT-B and the lipopolysaccharide (LPS) of the vaccine strain. Anti-LT-B and anti-LPS responses in the sera were predominantly of the IgG class whereas gut-associated antibodies were predominantly IgA. ELISPOT assays carried out on selected tissues prepared from vaccinated mice showed significant numbers of cells synthesising IgG and IgA antibodies to LT-B. These results show that Y. enterocolitica aroA mutants can be used effectively as carriers of heterologous antigens to the murine immune system.
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PMID:Yersinia enterocolitica aroA mutants as carriers of the B subunit of the Escherichia coli heat-labile enterotoxin to the murine immune system. 227 86

The relationship between the IgA antibody response in serum (total and polymeric IgA) and intestinal secretions was examined in volunteers subjected to oral and parenteral typhoid vaccination. After oral vaccination (three doses of 10(11) live Ty21a vaccine given at 48-hr intervals), serum pIgA antibody to typhoid lipopolysaccharide (LPS) was detected in seven of the 14 subjects (46.4 +/- 59 U/100 microliters, mean +/- SD). However, all 14 showed a significant intestinal IgA response (993 +/- 2516 and 9349 +/- 6754 U/mg pre- and post-vaccine; t = 5.25, P = 0.0002). The level of pIgA antibody declined rapidly, whereas intestinal IgA antibody levels remained elevated. Serum pIgA antibody was also found after parenteral immunization (two doses of 5 X 10(8) heat-killed bacteria given 14 days apart to six subjects), but an intestinal IgA antibody response was detected in these individuals only after a subsequent course of the oral vaccine given 1 month after initial parenteral immunization. Changes in serum pIgA antibody followed those of total serum IgA antibody rather than those of intestinal antibody. The results indicate that a serum pIgA response can be induced by an antigenic stimulus delivered either orally or parenterally, whereas an intestinal IgA response is induced only by a local antigen stimulus. The regulation of serum pIgA and intestinal IgA appear to be independent.
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PMID:The serum polymeric IgA antibody response to typhoid vaccination; its relationship to the intestinal IgA response. 230 80

The addition of transforming growth factor type beta to lipopolysaccharide-stimulated murine B-cell cultures enhances isotype switching to IgA and induces the appearance of two sizes of alpha mRNA transcripts. One of these is the same size as mRNA for secreted IgA but the other, which is 300-400 base pairs (bp) shorter, does not correlate in size with any form of productive alpha mRNA. Both sizes of transcript were shown to contain germ-line sequences 5' to the alpha switch region, suggesting that the longer transcripts included both germ-line and productive forms of alpha mRNA, whereas the shorter transcripts were only germ-line alpha mRNA. We isolated cDNA clones corresponding to the shorter, 1.3-kilobase (kb), transcript by using an anchored polymerase chain reaction and a specific primer for the constant region. Analyses of these cDNA clones show that the short transcript consists of a 126-bp exon located approximately 1.5 kb 5' to the alpha switch region spliced to the first exon of the alpha constant region locus. Furthermore, a minor fraction of the longer, approximately 1.7 kb, transcripts also contains this exon. These results demonstrate that transforming growth factor type beta-mediated isotype switching to IgA is preceded by transcriptional activation of the heavy-chain locus.
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PMID:Molecular characterization of germ-line immunoglobulin A transcripts produced during transforming growth factor type beta-induced isotype switching. 233 32

The subclass distribution of the IgG and IgA antibody response in serum was studied in humans exposed to aerosolized metal-working fluid containing Pseudomonas pseudoalcaligenes. This species was consistently found in concentrations of 10(8) bacteria per milliliter of metal-working fluid during 1 year of observation. No increased frequency of respiratory infections or discomfort was related to the exposure to the infected fluid. The antibody response to the bacterium consisted predominantly of IgG1 and IgG2 antibodies. IgG2 antibodies dominated the antibody response to the lipopolysaccharide of the bacterium. IgA1 and IgA2 antibodies were also found. Smokers had significantly reduced antibody levels of all subclasses compared with nonsmokers. The antibody levels in smokers did not differ from levels of the unexposed control group. Analyses of the total serum immunoglobulin concentrations with respect to subclasses revealed that the total IgG2 levels were also significantly reduced in smokers. In nonsmokers, the age of the individuals influenced the antibody levels of the IgG1, IgG2, IgA1, and IgA2 subclasses, the levels decreasing with increasing age. For smokers, the correlation between age and antibody levels was only obvious for IgG2 antibodies. Decreased IgG2 antibody levels in the smokers were also accompanied by decreased FEV1 values (p less than 0.01). Subclass analysis of the antibody response to P. pseudoalcaligenes demonstrated that the subclass pattern for the whole bacterium differed from the pattern of the major cell wall component, the lipopolysaccharide. The significance of qualitative and quantitative differences in the subclass antibody response is discussed.
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PMID:Subclass distribution of IgG and IgA antibody response to Pseudomonas pseudoalcaligenes in humans exposed to infected metal-working fluid. 238 50

A quantitative analysis of immunocompetent cells in the middle ear mucosa of mice was carried out by an indirect immunostaining method using various monoclonal antibodies. Mice bred in germ-free, specific pathogen-free, and conventional conditions were used to examine nonimmunized middle ear mucosa. Middle ear mucosae of otitis media-induced mice were also examined. In normal middle ear mucosa, mast cells were substantial, followed by Mac-1-positive cells and lymphocytes. Even though IgA-, IgM-, and Lyt-1-positive cells were seen in the mucosa of conventional mice, IgM-positive cells were seen only in mucosae of specific pathogen-free and germ-free mice. In otitis media-induced mice by inoculation with nontypable Haemophilus influenzae or lipopolysaccharide, Mac-1-positive cells were dominant. Although the numbers of IgM- and Lyt-1-positive cells increased markedly, the numbers of other lymphocyte subsets did not increase until 14 days after inoculation. These findings suggest that the middle ear is immunologically a potential organ as long as it is not exposed to antigenic stimulation. It is considered to be an immunoreactive site only after it has been activated with pathogens.
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PMID:Analysis of immunocompetent cells in the middle ear mucosa. 240 71

This study was done to define antigens important in the immune response to infection with Neisseria gonorrhoeae. Sera were obtained from men and women with uncomplicated gonorrhea (UGC), women with disseminated gonococcal infection, and women with gonococcal pelvic inflammatory disease (PID); sera were also obtained from uninfected controls. Vaginal fluids were taken from 15 patients with UCG or PID. The sera and vaginal fluids were tested against gonococcal isolates from the same patients to examine homologous antibody-antigen interactions by use of the western blot technique. Antibodies in the serum reacted with more gonococcal antigens compared with antibodies in the vaginal fluid. IgG in serum and vaginal fluid reacted with more antigens than did IgA in the same specimens. The predominant antigens reactive with IgG in serum were pili, protein II, a broad 23-33-kDa band of antigen, and presumptive lipopolysaccharide; and for IgA, protein II and a 46-48-kDa protein. The control sera also reacted with the 46-48-kDa protein. The predominant antigens reactive with IgG in vaginal fluid were protein I, protein II, pili, and the 46-48-kDa protein; and for IgA, protein I, protein II, and pili. Immunoglobulin in vaginal fluid reacted comparatively more with protein I than did immunoglobulin in serum.
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PMID:Antibody-antigen specificity in the immune response to infection with Neisseria gonorrhoeae. 241 48

The antibody specificity repertoire of lipopolysaccharide (LPS)-reactive B cells has been determined in the spleens and bone marrow (BM) of C57BL/Ka athymic nude mice using a limiting dilution culture system that allows the growth and development of every LPS-reactive B cell into a clone of IgM-secreting cells. In addition, the numbers of "spontaneously" occurring ("background") IgM-, IgG-, and IgA-secreting cells as well as the "background" IgM antibody specificity repertoire has been assessed in spleens and BM. The frequencies of antigen-specific LPS-reactive B cells of C57BL/Ka nude and thymus-bearing mice showed a great similarity and ranged from 1 in 1000 to 1 in 2500 for sheep red blood cells (SRBC), horse red blood cells (HRBC), and goat red blood cells (GRBC), from 1 in 10 to 1 in 25 for 5-iodo-3-nitrophenyl-coupled (SRBC), from 1 in 15 to 1 in 150 for 4-hydroxy-3,5-dinitrophenyl-coupled SRBC, and from 1 in 70 to 1 in 140 for 2,4,6-trinitrophenyl-coupled SRBC. The specificity repertoire of the "background" IgM-secreting cells differed from that of age-matched thymus-bearing controls and was different in young and old C57BL/Ka nude mice. Within the limitations of having assessed only a minor fraction of the total B-cell antibody specificity repertoire and supposing that nude mice are largely devoid of functional T cells, the data presented suggest that the generation of the specificity repertoire of newly-formed B cells is hardly or not affected by T cells. On the other hand, T cells do affect the expression of the established repertoire, represented by "background" immunoglobulin-secreting cells.
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PMID:Frequency analysis of the antibody specificity repertoire of mitogen-reactive B cells and "spontaneously" occurring "background" plaque-forming cells in nude mice. 241 79

An IgA monoclonal antibody (MUM/F1-1/copenhageni) was produced from a mouse immunised with Leptospira interrogans serovar copenhageni. The antibody showed partial serogroup specificity by agglutination and by reaction in enzyme immunoassay, and opsonised homologous leptospires for phagocytosis by cultured mouse macrophages. Immunodiffusion and Western-blotting experiments indicated that MUM/F1-1/copenhageni reacted with a carbohydrate determinant in the leptospiral lipopolysaccharide. Daily administration of purified MUM/F1-1/copenhageni IgA before and after challenge with 2 X 10(8) virulent homologous leptospires passively protected newborn guinea pigs against lethal leptospirosis.
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PMID:A monoclonal antibody reacting with a determinant on leptospiral lipopolysaccharide protects guinea pigs against leptospirosis. 243 Jan 3

We genetically modified attenuated Salmonella typhi strain Ty21a to express the form I O polysaccharide antigen of Shigella sonnei. Three doses of this bivalent, live oral vaccine strain (1-8 X 10(9) organisms/dose) were given to young adults who, along with unvaccinated controls, were challenged one month later with pathogenic S. sonnei. The vaccinees had 40% protection against diarrhea and 56% against Hematest-positive diarrhea. Two of three vaccine lots provided higher levels of protection (53% against diarrhea and 71% against Hematest-positive diarrhea), but the third lot, prepared for a large-scale field trial, demonstrated no protective efficacy. Vaccinees had serum and local intestinal immune responses to S. sonnei lipopolysaccharide, and the presence of specific serum IgA or IgG antibody before challenge with pathogenic S. sonnei was correlated with protection from illness. Some lots of this bivalent vaccine strain provide significant protection against S. sonnei disease, but the problem of lot-to-lot variability must be overcome.
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PMID:Prevention of shigellosis by a Salmonella typhi-Shigella sonnei bivalent vaccine. 243 20


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