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)

We have previously reported the detection of endotoxin in the amniotic fluid of patients with gram-negative intraamniotic infection. Endotoxin or lipopolysaccharide is a potent biologic product capable of inducing prostaglandin release from several cell types and, therefore, may be involved in the onset of human parturition in the presence of intraamniotic infection. This article describes a technique for the quantification of endotoxin in amniotic fluid. The method uses a computer-assisted quantification of the turbidimetric reaction between the Limulus amebocyte lysate and endotoxin. Serial dilutions of Escherichia coli endotoxin in culture-negative amniotic fluid were prepared, and the samples were run in the assay. Amniotic fluid was found to enhance the reaction, and a dilution of 1:20 was required for this biologic fluid to behave similarly to pyrogen-free water. The sensitivity of this kinetic turbidimetric technique in the detection of endotoxin in amniotic fluid was 40 pg/ml. This method was applied to the quantification of endotoxin concentration in amniotic fluid in 26 patients with intraamniotic infection and premature rupture of membranes. Patients in active labor had higher concentrations of endotoxin (median = 47,514 pg/ml) than nonlaboring patients (median = 635 pg/ml) (p less than 0.025). Therefore, women with preterm labor had a higher median concentration of endotoxin in amniotic fluid than patients who were not in labor.
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PMID:Labor and infection. II. Bacterial endotoxin in amniotic fluid and its relationship to the onset of preterm labor. 336 83

Infection is believed to be a leading cause of preterm premature rupture of membranes (PPROM). The bacterial cell wall component, lipopolysaccharide (LPS), is thought to initiate tissue responses leading to PPROM in the setting of Gram negative infection. LPS is recognized by the innate immune system, including the proteins encoded by the CARD15 and TLR4 genes. A recently described mutation (2936insC) in CARD15 and a polymorphism in TLR4 896 A>G impair responses to LPS. The objective of this study was to determine if African Americans, who have a higher incidence of PPROM than Caucasians, have different frequencies of the mutant CARD15 allele and the TLR4 hyporesponsive variant, and if risk of PPROM is influenced by fetal carriage of these alleles. The allele frequencies for the CARD15 mutation and the TLR4 896G variant in African Americans were similar to those reported for Caucasians. There was no association between the TLR4 alleles examined and PPROM. However, the CARD15 mutation was only detected in controls and not in PPROM cases. We conclude that the CARD15 mutation and hyporesponsive TLR4 allele do not contribute to ethnic variation in the incidence of PPROM.
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PMID:The CARD15 2936insC mutation and TLR4 896 A>G polymorphism in African Americans and risk of preterm premature rupture of membranes (PPROM). 1239 16

CD14, the major receptor for bacterial lipopolysaccharide (LPS) as well as other microbial antigens, is a component of the innate immune system. We hypothesized that a single nucleotide C>T polymorphism at position -159 in the CD14 gene that results in elevated CD14 production would influence susceptibility to preterm premature rupture of membranes (PPROM) and spontaneous preterm birth (SPTB) in multi-fetal pregnancies. DNA from 107 mother-twin and three mother-triplet pairs was analyzed. Pregnancy outcomes were obtained after completion of testing. CD14*T homozygosity was present in 39.3% of 28 women whose pregnancies ended with PPROM, as opposed to 18.1% of 72 pregnancies without a SPTB (P=0.03). There was no relation between the fetal CD14 genotype and PPROM. The likelihood ratio (LR) for PPROM was 2.2 for women homozygous for CD14*T. The LR increased to 3.3 and 3.6 if the CD14 polymorphism was present in combination with previously determined maternal polymorphisms in the genes coding for the inducible 70kDa heat shock protein (hsp70-2) and the interleukin-1 receptor antagonist (IL1RN), respectively. Thus, an enhanced maternal pro-inflammatory immune response to LPS may increase susceptibility to PPROM in multi-fetal pregnancies.
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PMID:Association of a maternal CD14 -159 gene polymorphism with preterm premature rupture of membranes and spontaneous preterm birth in multi-fetal pregnancies. 1642 40

Bacterial infection-associated inflammation is thought to be a major cause of preterm premature rupture of membranes. Proinflammatory cytokines, such as interleukin 1B (IL1B), can weaken fetal membranes (FM) by upregulating matrix metalloproteinases and inducing apoptosis. The mechanism by which infection leads to inflammation at the maternal-fetal interface and subsequent preterm birth is thought to involve innate immune pattern recognition receptors (PRR), such as the Toll-like receptors (TLR) and Nod-like receptors (NLR), which recognize pathogen-associated molecular patterns (PAMPs). The objective of this study was to determine the cytokine profile generated by FMs in response to the bacterial TLR and NLR agonists peptidoglycan (PDG; TLR2), lipopolysaccharide (LPS; TLR4), flagellin (TLR5), CpG ODN (TLR9), iE-DAP (Nod1), and MDP (Nod2). PDG, LPS, flagellin, iE-DAP, and MDP triggered FMs to generate an inflammatory response, but the cytokine profiles were distinct for each TLR and NLR agonist, and only IL1B and RANTES were commonly upregulated in response to all five PAMPs. CpG ODN, in contrast, had a mild stimulatory effect only on MCP-1 and primarily downregulated basal FM cytokine production. IL1B secretion induced by PDG, LPS, flagellin, iE-DAP, and MDP was associated with its processing. Furthermore, FM IL1B secretion in response to TLR2, TLR4, and TLR5 activation was caspase 1-dependent, whereas Nod1 and Nod2 induced IL1B secretion independent of caspase 1. These findings demonstrate that FMs respond to different bacterial TLR and NLR PAMPs by generating distinct inflammatory cytokine profiles through distinct mechanisms that are specific to the innate immune PRR activated.
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PMID:Human fetal membranes generate distinct cytokine profiles in response to bacterial Toll-like receptor and nod-like receptor agonists. 2442 16