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)

Antibodies to the lipopolysaccharide (LPS) and protein antigens of S. typhi in secretions of small intestine obtained from 12 typhoid patients, four typhoid carriers and 16 non-typhoid control subjects were measured by a solid-phase radioimmunoassay technique. Intestinal secretions obtained from typhoid patients as a group had significantly higher anti-LPS and anti-protein antibodies than those from the control group. These antibodies were both IgM and IgA classes. There was no correlation between the IgM or IgA antibody levels in serum and those in the intestinal secretions. In the intestinal secretions obtained from typhoid carriers, on the other hand, only IgA-class antibodies to the LPS and protein antigens of S. typhi were present at high levels.
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PMID:Antibody response to the lipopolysaccharide and protein antigens of Salmonella typhi during typhoid infection. II. Measurement of intestinal antibodies by radioimmunoassay. 733 78

The difference in natural resistance to Salmonella typhimurium between S. typhimurium-resistant A/J mice and S. typhimurium-susceptible C57BL/6 mice was analyzed. In both strains, the growth of S. typhimurium was controlled in the spleen until 48 hr of infection, while serum C3b levels were increased in A/J mice immediately after infection but not in C57BL/6 mice. Incubation of A/J mouse serum with S. typhimurium or its lipopolysaccharide (LPS) generated sufficient amounts of C3b, but that of C57BL/6 mouse serum with them did not. A/J macrophages had higher intracellular killing activity in vitro than did C57BL/6 cells against S. typhimurium pre-opsonized with each corresponding fresh serum. However, the cells from both mice exhibited a similar level of killing activity against S. typhimurium pre-opsonized with fresh A/J serum or rabbit complement. The resistance of C57BL/6 mice was significantly increased by opsonizing S. typhimurium with fresh A/J serum or rabbit complement before inoculation. The serum level of interferon-gamma (IFN-gamma) in A/J mice was 2.7 times as high as in C57BL/6 mice at 48 hr post-infection. Recombinant murine IFN-gamma enhanced the intracellular killing activity of macrophages from both mice when S. typhimurium was pre-opsonized with fresh A/J serum but not with fresh C57BL/6 serum. These findings suggest that A/J macrophages exhibit maximal killing activity against A/J serum-opsonized S. typhimurium in vivo when the cells are activated with IFN-gamma. Therefore, the rapid and sufficient activation of complement by Salmonella LPS may render A/J mice more resistant against murine typhoid.
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PMID:Different sensitivity of complement to Salmonella typhimurium accounts for the difference in natural resistance to murine typhoid between A/J and C57BL/6 mice. 778 91

Circulating proinflammatory mediators have not been found in studies on typhoid fever, although the patients suffer from a systemic disease with characteristic protracted fever. The 14-kDa group II extracellular phospholipase A2 (PLA2) is induced by interleukin-1 and tumor necrosis factor and may mediate some of the effects of these cytokines. Circulating PLA2 concentrations were measured in 12 typhoid fever patients on various days after admission and after recovery. On admission, mean concentrations of PLA2 were elevated (1444 +/- 1560 ng/mL) and decreased gradually and significantly to day 14 (55 +/- 48 ng/mL). patients with complicated disease had significantly higher PLA2 levels on admission. PLA2 was not produced in a lipopolysaccharide-stimulated whole blood culture, indicating that PLA2 originates from other types of cells. These data indicate that PLA2 may be a mediator of disease in protracted inflammatory diseases such as thyroid fever.
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PMID:Phospholipase A2 is a circulating mediator in typhoid fever. 779 37

Cytokines and inhibitors in plasma were measured in 44 patients with typhoid fever. Ex vivo production of the cytokines was analyzed in a whole blood culture system with and without lipopolysaccharide (LPS). Acute phase circulating concentrations of cytokines (+/- SD) were as follows: interleukin (IL)-1 beta, < 140 pg/mL; tumor necrosis factor-alpha (TNF alpha), 130 +/- 50 pg/mL; IL-6, 96 +/- 131 pg/mL; and IL-8, 278 +/- 293 pg/mL. Circulating inhibitors were elevated in the acute phase: IL-1 receptor antagonist (IL-1RA) was 2304 +/- 1427 pg/mL and soluble TNF receptors 55 and 75 were 4973 +/- 2644 pg/mL and 22,865 +/- 15,143 pg/mL, respectively. LPS-stimulated production of cytokines was lower during the acute phase than during convalescence (mean values: IL-1 beta, 2547 vs. 6576 pg/mL; TNF alpha, 2609 vs. 6338 pg/mL; IL-6, 2416 vs. 7713 pg/mL). LPS-stimulated production of IL-1RA was higher in the acute than during the convalescent phase (5608 vs. 3977 pg/mL). Inhibited production of cytokines during the acute phase may be due to a switch from a proinflammatory to an antiinflammatory mode.
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PMID:Patterns of proinflammatory cytokines and inhibitors during typhoid fever. 819 8

The humoral response to Salmonella typhi is important for protective immunity against typhoid fever, as indicated by the protection obtained with killed cell vaccines and component vaccines (outer membrane proteins, Vi antigen) in animals and human beings. Nonetheless, analysis and interpretation of host humoral immune response to S. typhi surface antigens have been difficult because of the complex structure of the S. typhi envelope and the lack of purified reagents for detection of immune response to individual surface components. Normal and convalescent human sera from typhoid fever patients were absorbed with S. typhi lipopolysaccharide. These sera were used in radioimmunoprecipitation assays of whole S. typhi cells and S. typhi membranes labelled with either 125I or 35S-methionine. This strategy has permitted the unequivocal identification of a humoral immune response to structural and in vivo induced outer membrane proteins of S. typhi. In this manner, we have identified the porins, lipoprotein, the iron-starvation-induced proteins, and three proteins of 30, 18.5 and 15 kDa as surface-exposed immunogens of S. typhi in patients with typhoid fever. These studies suggest that further experimental work is needed to characterize the relevance of both anti-S. typhi outer membrane protein and antilipopolysaccharide antibodies in recovery from S. typhi infections and protective immunity.
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PMID:Lipopolysaccharide-independent radioimmunoprecipitation and identification of structural and in vivo induced immunogenic surface proteins of Salmonella typhi in typhoid fever. 842 32

The clinical and immunological responses to typhoid vaccination with parenteral and oral vaccines in two groups of 30 adult male subjects were studied. Specific anti-Salmonella typhi cell-mediated immunity and total or specific anti-lipopolysaccharide faecal immunoglobulin (Ig) A titres in vaccinated subjects were monitored. Cellular antibacterial activity was significantly increased only in orally vaccinated subjects. Serum arming activity and inhibition experiments suggested an IgA-dependent cellular cytotoxicity in those orally vaccinated. In these subjects, a total and anti-lipopolysaccharide faecal IgA increase was observed lasting up to 8 months after completion of the vaccination schedule. In parenteral vaccinated subjects, an early onset transitory increase of IgM rheumatoid factor was observed. Oral vaccine was well tolerated and free of side effects, whereas 65% of parenterally vaccinated subjects reported side effects such as fever, headache, malaise and local tenderness in the injection site.
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PMID:Clinical and immunological response to typhoid vaccination with parenteral or oral vaccines in two groups of 30 recruits. 848 16

An enzyme immunoassay (EIA) for detection of serum antibodies in patients with typhoid fever was developed using Salmonella typhi outer membrane protein (OMP) preparations as antigen. Acute phase (first week) sera from adult typhoid fever patients were tested as well as sera from the following control groups: adult travellers with diarrhea caused by enterotoxigenic Escherichia coli, children infected with Campylobacter jejuni, healthy Mexican adult blood donors, and adults with septicemia caused by other organisms. At a 1:3,125 serum dilution, the mean absorbance values were 1.41 in the typhoid fever patients, and 0.57, 0.55, 0.51 and 0.52 in the respective control groups. Inhibition EIA studies using OMP preparations or lipopolysaccharide (LPS) as free antigen indicated that proteins can play an important role in the detection of antibodies in early typhoid fever. This EIA may be useful for the diagnosis of typhoid fever since results were obtained within about five hours and in an endemic area antibodies against Salmonella typhi OMP preparations appear early in the course of the disease.
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PMID:Early diagnosis of typhoid fever by an enzyme immunoassay using Salmonella typhi outer membrane protein preparations. 851 12

Because of the limited value of Widal's test in the diagnosis of typhoid fever in areas of endemicity, individual serum levels of IgM, IgA, IgG, and IgG subclass antibodies to Salmonella typhi lipopolysaccharide were evaluated in samples collected in Egypt. The study involved 106 febrile patients, including 40 patients for whom cultures were positive for S. typhi and 66 patients for whom diseases other than typhoid were diagnosed. Multivariate regression modeling revealed that detection of the combination of IgA, IgG, and IgG2 correlated best, although not perfectly (adjusted r(2) = 68), with a positive culture; the sensitivity and specificity of testing for IgA, IgG, and IgG2 (i.e., all three tests positive vs. all three tests negative) were 91.7% and 98.1%, respectively. These results suggested that testing for IgA, IgG, and IgG2 in combination is of diagnostic value for S. typhi infection.
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PMID:Evaluation of the response of human humoral antibodies to Salmonella typhi lipopolysaccharide in an area of endemic typhoid fever. 864 89

The phoP/phoQ virulence regulatory genes of Salmonella typhi Ty2 were deleted, and the resultant strain (Ty800) was tested as a live attenuated typhoid fever vaccine in human volunteers. Groups of 2 or 3 subjects received single oral doses of 10(7), 10(8), 10(9), or 10(10) cfu. Two volunteers who received the largest dose had self-limited side effects; no bacteremias were detected. Ten of 11 subjects had evidence of intestinal immune responses to the vaccine as measured by increases in S. typhi lipopolysaccharide-specific IgA-secreting cells in peripheral blood samples. Humoral immune responses were measured and compared with those of control vaccinees who received 4 oral doses of S. typhi Ty21a. In the most sensitive assays, 9 of 11 volunteers and 5 of 8 Ty21a control vaccinees had evidence of IgG directed against S. typhi antigens. Ty800 is safe, and single oral doses are highly immunogenic in humans.
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PMID:phoP/phoQ-deleted Salmonella typhi (Ty800) is a safe and immunogenic single-dose typhoid fever vaccine in volunteers. 864 13

Whole blood cultures are used to study cytokine stimulation and release ex vivo. In the present study this method was compared with a more direct approach and a quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to assess mRNA expression for IL-1 beta and tumour necrosis factor alpha (TNF-alpha) and mRNA in whole blood. Stimulation of whole blood from normal donors with lipopolysaccharide (LPS) at various time intervals showed a parallel rise of immunogenic IL-1 beta and TNF-alpha as well as a rise of mRNA expression for IL-1 beta and TNF-alpha with peak levels for IL-1 beta after 4-6 h stimulation and for mRNA TNF-alpha expression after 2 h stimulation. These methods were used to explore cytokine production during the course of typhoid fever and after a 5 km run. In both conditions circulating cytokine concentrations were not influenced, but the TNF-alpha and IL-1 beta mRNA gene expression in circulating whole blood cells was increased in patients with typhoid fever. The LPS-stimulated production of TNF-alpha and IL-1 beta was decreased in both but there was no change for the mRNA content in whole blood for these cytokines. These findings demonstrate that RT-PCR is an attractive method to study the gene expression of cytokines in whole blood, an increased TNF-alpha and IL-1 beta gene expression is present in typhoid fever, and that the LPS stimulated downregulation of cytokines in exercise and typhoid fever may be mediated by post-transcriptional processes.
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PMID:A semi-quantitative reverse transcriptase polymerase chain reaction method for measurement of MRNA for TNF-alpha and IL-1 beta in whole blood cultures: its application in typhoid fever and exentric exercise. 893 86


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