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 effects of techniques commonly used in the collection and processing of human intestinal fluid on the specific secretory immunoglobulin A (sIgA) response following oral immunization with the live typhoid vaccine Salmonella typhi Ty21a were examined. It was observed that the failure to adjust specific intestinal anti-typhoid lipopolysaccharide IgA antibody titres for total secretory IgA resulted in a false-negative detection rate of 19.8% and a false-positive detection rate of 7.4%. Furthermore, these specific responses were significantly diminished if the intestinal fluid was subjected to heat inactivation to reduce intestinal protease activity (p = 0.0083), but were not affected if stored at -70 degrees C for up to 1 year, without heat inactivation. It was concluded that in the processing of the intestinal fluid samples for specific sIgA determination heat inactivation significantly reduced specific sIgA titres, and that the failure to adjust absolute titres for total sIgA content resulted in a significant false-negative detection rate.
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PMID:Effects of sample processing on the measurement of specific intestinal IgA immune responses. 144 35

We carried out a study in patients with severe neutropenia from hematologic malignancy and suspected gram-negative sepsis to evaluate the clinical significance of endotoxin concentrations in plasma before and during a therapeutic intervention with a human polyclonal immunoglobulin M (IgM)-enriched immunoglobulin preparation (Pentaglobin; Biotest, Dreieich, Germany). Twenty-one patients with acute leukemia or non-Hodgkin's lymphoma entered the study upon the development of clinical signs of gram-negative sepsis and received the IgM-enriched immunoglobulin preparation every 6 h for 3 days (total dose, 1.3 liter with 7.8 g of IgM, 7.8 g of IgA, and 49.4 g of IgG), in addition to standardized antibiotic treatment. Concentrations of endotoxin and IgM and IgG antibodies against lipid A and Re lipopolysaccharide (LPS) in plasma were determined by a modified chromogenic Limulus amebocyte lysate test and semiquantitative enzyme linked immunosorbent assay, respectively, before each immunoglobulin infusion and during the following 25 days. Seventeen patients were endotoxin positive; in five of these patients, gram-negative infection was confirmed by microbiologic findings. Prior to therapy, endotoxemia correlated significantly with the occurrence of fever, and a quantitative correlation between the endotoxin concentration and body temperature was found during the individual course of infection in 8 of the 17 patients. Overall mortality from endotoxin-positive sepsis was 41% (7 of 17) and 64% (7 of 11) in patients with symptoms of septic shock. Nonsurvivors had significantly higher maximum concentration of endotoxin in plasma compared with those of survivors at the first study day (median of 126 versus 34 pg/ml; P < 0.05) and during the whole septic episode (median of 126 versus 61 pg/ml; P < 0.05). In survivors, immunoglobulin therapy resulted in a significant decrease in endotoxin levels in plasma within the initial 18-h treatment period, from a pretreatment median value of 28 pg/ml to a value of 8 pg/ml (P< 0.05). In the seven patients who died from uncontrollable infection, no effect of therapy on endotoxin levels in plasma was observed. IgM and IgG antibodies against lipid A and Re LPS increased significantly under immunoglobulin treatment, with significant correlations between antibodies against lipid A and Re LPS. These data strongly suggest a prognostic significance of the endotoxin levels in plasma and a potential effect of treatment with a polyclonal IgM-enriched immunoglobulin preparation. Further studies are needed to substantiate these findings and to assess the impact on the clinical course by way of a prospective placebo-controlled clinical trial.
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PMID:Endotoxin concentration in neutropenic patients with suspected gram-negative sepsis: correlation with clinical outcome and determination of anti-endotoxin core antibodies during therapy with polyclonal immunoglobulin M-enriched immunoglobulins. 144 93

We conducted a prospective, community-based study of healthy breast-fed Mexican infants to determine the protective effects of anti-Shigella secretory IgA antibodies in milk. Milk samples were collected monthly, and stool culture specimens were obtained weekly and at the time of episodes of diarrhea. Nineteen breast-fed infants were found to have Shigella flexneri, Shigella boydii, or Shigella sonnei in stool samples. Ages of the 10 infants with symptomatic infection and the nine with asymptomatic infection did not differ significantly. Milk samples collected up to 12 weeks before infection were evaluated by enzyme-linked immunosorbent assay for secretory IgA antibodies against lipopolysaccharides of S. flexneri, S. boydii serotype 2, S. sonnei, and virulence plasmid-associated antigens. The geometric mean titers of anti-Shigella antibodies to virulence plasmid-associated antigens in milk received before infection were eightfold higher in infants who remained well than in those in whom diarrhea developed. The significance of milk secretory IgA directed against lipopolysaccharide was less clear. We conclude that human milk protects infants against symptomatic shigella infection when it contains high concentrations of secretory IgA against virulence plasmid-associated antigens.
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PMID:Concentration of milk secretory immunoglobulin A against Shigella virulence plasmid-associated antigens as a predictor of symptom status in Shigella-infected breast-fed infants. 144 44

Interleukin-2, pokeweed mitogen, and lipopolysaccharide were evaluated for their ability to accelerate involution and to stimulate local cellular defenses in the nonlactating bovine mammary gland. Twelve cows were divided into three treatment groups of 4 cows each to receive interleukin-2, pokeweed mitogen, or lipopolysaccharide. One day after drying off, 3 mammary quarters of each cow were infused with 100 micrograms of immunostimulant daily for 21 d; the remaining control quarter received PBS. Secretion samples were collected weekly to determine bacteriologic status, total SCC, and differential cell counts. On d 21, cows were killed, and tissues were collected for microscopy. Overall, SCC were higher in immunostimulated quarters, but only those infused with interleukin-2 were significantly elevated over controls. By wk 3, the percentage of neutrophils decreased in interleukin-2 and pokeweed mitogen quarters over pretreatment values, percentage of macrophages increased in interleukin-2 quarters, and percentage of lymphocytes increased in pokeweed mitogen and lipopolysaccharide quarters. Percentage of alveolar lumina was reduced, and connective tissue stroma increased, in all immunostimulated quarters compared with those of controls, suggesting accelerated involution. Involution was greatest in quarters treated with interleukin-2. Leukocyte infiltration was greater in immunostimulated quarters than in control quarters. Similarly, concentrations of Ig-producing plasma cells were greater in immunostimulated quarters than in control quarters. Quarters infused with interleukin-2 exhibited the greatest concentration of plasma cells, followed by quarters treated with pokeweed mitogen and lipopolysaccharide; IgG1 plasma cells predominated, followed by IgG2, IgA, and IgM. Interleukin-2 accelerated involution and stimulated local antibody production more than did the two mitogens, suggesting a potential role for this cytokine as a general immunostimulant at drying off.
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PMID:The effect of chronic immunostimulation of the nonlactating bovine mammary gland with interleukin-2, pokeweed mitogen, and lipopolysaccharide. 147 3

B lymphocytes expressing surface IgM with or without IgD may switch to the expression of other isotypes (IgG, IgA, or IgE) in the course of immune responses. Analyses of genomic DNA from cloned myelomas and hybridomas have shown that the isotype switch is accompanied by a rearrangement characterized by deletion of DNA between the switch (S) region of the mu gene and that associated with the new isotype, resulting in the formation of a composite S region. Measurement of this deletional rearrangement has been difficult in populations of normal B cells but would be useful for investigating the mechanism of the rearrangement and determining whether deletional rearrangement is responsible for all instances of class switching. We have developed a sensitive assay for deletional rearrangement that we designate the digestion-circularization polymerase chain reaction (PCR). In this assay, genomic DNA is digested with a restriction enzyme that recognizes sites that flank the recombined composite S region. The digested DNA is then ligated at low concentrations to favor the formation of circles. The ligation joins the 5' and 3' ends of each restriction fragment, making it possible to amplify by PCR across the ligated restriction site by using appropriate primers. From DNA that has undergone deletional rearrangement, a single-sized PCR product is produced and can be quantitated. We demonstrate here that the digestion-circularization PCR assay can detect S mu-S gamma 1 rearrangements in B cells cultured with lipopolysaccharide and interleukin 4. The assay is sensitive enough to quantitate switched cells constituting only 1-2% of the population.
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PMID:Quantitation of immunoglobulin mu-gamma 1 heavy chain switch region recombination by a digestion-circularization polymerase chain reaction method. 149 89

Enzyme immunoassays (EIA) were used to estimate titres of class-specific antibodies against purified and chemically defined phenol-water-extracted lipopolysaccharide (LPS) antigens of Salmonella serogroup B (BO), Shigella dysenteriae type I, Plesiomonas shigelloides (the same O-antigen as Shigella sonnei) and Shigella flexneri Y. Titres in colostrum and breast milk of Swedish, Vietnamese and Costa Rican mothers from various socioeconomic conditions were compared. The antibodies were mainly of the IgA isotype. IgM antibodies were also present, but only very low concentrations of IgG were found. In Costa Rican mothers, the IgA antibody titres were significantly higher (P less than 0.05) in women of low and middle socioeconomical conditions than were those in mothers of high socioeconomical level. The low titres in the last group were comparable to those found in Swedish mothers. The IgA antibody titres found in Vietnamese mothers were similar to those of Costa Rican mothers from the low and middle socioeconomic conditions, being highest against S. flexneri Y LPS. The IgM antibody titres were also highest in Vietnamese mothers, immediately followed by the Costa Rican mothers of low socioeconomic conditions. The low IgM titres in the Costa Rican women of high socioeconomic level were comparable to those seen in Swedish mothers. The results suggest that, in Costa Rica and Vietnam, S. flexneri is the most prevalent Shigella sp. causing infection and that Salmonella serogroup B infections are rare in all three countries. The results also show that the antibody repertoire in colostrum and breast milk varies. Furthermore, in addition to the prevalence of a specific micro-organism in a determined geographical area, such differences may be associated mainly with exposure to certain pathogens in particular socioeconomic conditions.
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PMID:Titres of class-specific antibodies against Shigella and Salmonella lipopolysaccharide antigens in colostrum and breast milk of Costa Rican, Swedish and Vietnamese mothers. 152 29

A 10-month-old Arabian foal was evaluated for a suspected immunoglobulin (Ig) M deficiency. Decreased to nondetectable concentrations of IgM, IgA, and IgG (T), and a normal concentration of IgG, were present. Results of in vitro testing of the blood lymphocyte blastogenesis showed a weak response to the B-cell mitogen, lipopolysaccharide (LPS), but normal responses to T-cell mitogens. Results of postmortem examination showed synovitis of the left tibiotarsal and both scapulohumeral joints. Atrophy and edema of the lymph nodes and lymphocyte depletion in the thymus and spleen were seen. A subacute inflammatory infiltrate was observed in the kidney, synovium, liver, and brain. Etiologic agents were not identified. This case represents a previously unreported form of immunodeficiency disease in the horse.
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PMID:Unusual selective immunoglobulin deficiency in an Arabian foal. 152 50

CD23 is a surface marker of activated B cells as well as a low-affinity Fc receptor for IgE. In this study, we enumerated CD23-positive peripheral blood lymphocytes and evaluated their clinical significance in patients with IgA nephropathy (IgAN). Twenty-five patients with IgAN and 16 patients with non-IgA proliferative glomerulonephritis (PGN) were studied. Twenty-seven healthy adults served as controls. CD23-bearing cells were enumerated by flow cytometry, and serum IgE levels were measured by latex photometric immunoassay. Significant increases in the number of CD23-positive cells were observed in patients with IgAN (p less than 0.01) and PGN (p less than 0.05) compared with controls. A significant elevation of serum IgE levels was also observed in the patients with IgAN and PGN (p less than 0.05). No positive correlation between the number of CD23-positive cells and serum IgE levels was observed. We also examined the induction of surface CD23 expression on peripheral lymphocytes by interleukin (IL)-2, IL-3, IL-4, IL-5, IL-6, interferon (IFN)-gamma, IFN-alpha, phytohemagglutinin, concanavalin A, pokeweed mitogen, lipopolysaccharide and phorbol myristate acetate. IL-4 was revealed to have a significantly potent effect on the induction of cell surface CD23 compared with other stimulants. It was concluded that many patients with IgAN or PGN show high serum IgE levels and/or high CD23-positive cell counts in their peripheral blood, suggesting that hyperactivation of B cells might be involved in the development of IgAN and non-IgA PGN. It appeared that IL-4 may play a significant role in the etiology of these types of glomerulonephritis.
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PMID:Increase of CD23-positive cells in peripheral blood from patients with IgA nephropathy and non-IgA proliferative glomerulonephritis. 153 1

One-hundred serum samples from 41 patients suffering from Mediterranean spotted fever (MSF) were tested by microimmunofluorescence (MIF) and Western blot (WB; immunoblot). Immunoglobulin G (IgG), IgM, and IgA antibody-specific responses to the high-molecular-mass species-specific protein antigens (115 kDa and 135 kDa) of Rickettsia conorii, as well as to cross-reactive lipopolysaccharide (LPS) antigens, were observed. The WB assay detected IgM-type antibodies earlier than did the MIF assay. These antibodies were often directed against nonspecific LPS and may have a questionable positive predictive value. In addition, an IgG reaction to a 60-kDa protein was observed in four cases of malignant forms of MSF but was never observed in cases of mild forms. This reaction could be correlated with a marker of the severity of the development of MSF. From a previous MIF survey of blood donors, 9 negative, 11 IgG-positive, and 6 IgM-positive serum samples were selected for comparison by WB. Sera negative by MIF were also negative by WB. MIF IgG-positive sera showed a specific response to R. conorii in the WB assay, but the six serum samples from this seroepidemiological study positive for IgM by MIF were almost all negative by the WB assay. One was positive for IgM against the LPS but was considered a false positive. The WB is shown to provide a new tool for serodiagnosis.
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PMID:Comparison of Western immunoblotting and microimmunofluorescence for diagnosis of Mediterranean spotted fever. 153 16

During the second half of murine pregnancy there is a characteristic increase in the number of spontaneous immunoglobulin-secreting cells in the maternal spleen (IgM, IgG and IgA), the uterus-draining lymph nodes (IgG) and Peyer's patches (IgA). There are indications that signals originating from the feto-placental unit are of importance for the generation of at least some of these changes. To evaluate further the role of placental factors as regulators of maternal Ig-secretion, placental extract (PE) was separated into eight fractions by gel-chromatography and each fraction was screened for its effect on splenic (1) background DNA-synthesis, (2) background Ig-secretion and (3) Ig-secretion in lipopolysaccharide (LPS) activated B-cells (anti-Thy1.2 + complement-treated splenocytes). Similarly prepared extracts of fetuses, maternal spleen and maternal liver served as controls. All tissue extracts and splenocytes were syngeneic to avoid reaction to allogeneic determinants. Placental extract fractions did not differ significantly from the other tissue extracts in affecting background lymphocyte activity. However, fraction number 3 from placental extract (PE3, corresponding to an approximate molecular weight of 18-70 kDa) was found strongly to increase the number of IgA-secreting cells (P less than or equal to 0.001) in LPS-activated B-cells. This effect was absent or much less pronounced in the corresponding controls. Blocking of PE3-activity by antibodies against rat prolactin indicated that the enhancing activity may be attributed to proteins of the prolactin/placental lactogen/growth hormone family. This assumption was further strengthened by experiments demonstrating that prolactin exerted preferential enhancement of IgA secretion when added to LPS-activated B-cell cultures in vitro. The possible role of placental prolactin-like molecules as regulators of maternal IgA secretion is discussed.
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PMID:A fraction of murine placental extract enhances IgA production in cultured splenocytes. 154 31


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