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)

Afipia clevelandensis is a recently described gram-negative bacterium whose potential pathogenic role in human disease is under investigation. Only one strain, from the pretibial lesion of a patient hospitalized with necrotizing pancreatitis for 5 months, has been isolated. Using an indirect immunofluorescence assay to detect anti-A. clevelandensis antibodies, we found a seroprevalence of 1.5% among 30,194 sera routinely submitted for laboratory diagnosis of rickettsial diseases. However, among the 52 patients who were clinically evaluable and who exhibited detectable antibodies against A. clevelandensis, 42% were eventually diagnosed as certainly or probably having brucellosis and 15% were eventually diagnosed as certainly or probably having Yersinia enterocolitica O:9 infection, which is the serotype most often encountered in Europe. Western immunoblotting and cross-adsorption tests showed that an 11.5-kDa proteinase K-labile band and a 21-kDa proteinase-stable band, presumably lipopolysaccharide, were responsible for cross-reactivity among A. clevelandensis, Brucella abortus, and Y. enterocolitica O:9. Other diagnoses included nosocomial infections and various community-acquired diseases for which the role of A. clevelandensis remains undefined. Physicians and clinical microbiologists should be aware of this cross-reactivity in future assessments of the role of A. clevelandensis in human pathology.
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PMID:Afipia clevelandensis antibodies and cross-reactivity with Brucella spp. and Yersinia enterocolitica O:9. 938 2

Sheep brucellosis, a zoonosis mainly due to B. melitensis (biovar 1, 2 or 3), remains widespread world-wide. Pathologically and epidemiologically, the disease is very similar to B. abortus infection in cattle. The live B. melitensis Rev 1 strain is currently considered as the best vaccine available for the control of sheep brucellosis, especially when used at the standard dose by the conjunctival route. Used exhaustively in whole-flock vaccination programmes, it induces a great decrease in the prevalence in both sheep and human populations. The expensive test-and-slaughter strategy should be restricted to the lowest infected areas. Whenever possible, Brucella spp. should be isolated by culture using adequate selective media from uterine discharges, aborted fetuses, udder secretions or selected tissues, such as lymph nodes, testes or epididymides. Species and biovar identification is routinely based on cultural criteria, on lysis by phages and on simple biochemical and serological tests. The recently developed polymerase chain reaction methods provide additional means of detection and identification. Despite the high degree of DNA homology within the genus Brucella, several methods, including PCR-RFLP and Southern blot, have been developed which allow, to a certain extent, the differentiation between Brucella species and some of their biovars. While several ELISA tests have been developed recently, the rose bengal plate agglutination and complement fixation tests, based on the detection of anti-S-LPS antibody, are still recommended for screening flocks and individuals. However, these tests sometimes lack specificity or sensitivity. For pooled samples, there are no useful tests such as the milk ring test in cattle. The brucellin allergic skin test can be used as a screening or complementary test in unvaccinated flocks, provided that a purified, lipopolysaccharide (LPS)-free and standardized antigen preparation is used.
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PMID:Brucella melitensis infection in sheep: present and future. 968 41

An indirect enzyme-linked immunosorbent assay (ELISA) for Brucella abortus antibodies detection in bovine milk and serum samples was validated. The assay use B. abortus smooth lipopolysaccharide as antigen, immobilized on a polystyrene matrix; milk diluted 1:2 or serum diluted 1:50, in a buffer containing divalent cation chelating agents EDTA and EGTA (ethyleneglycol-bis-aminoether-N,N,N',N'-tetraacetic acid) to reduce non-specific reactions; and a mouse monoclonal antibody specific for an epitope of bovine IgG1, conjugated with horseradish peroxidase. A total of 2646 sera and 2119 milk samples from cows older than 24 months were obtained from 12 brucellosis-free herds for at least the previous 5 years. Milk samples were obtained in parallel with serum samples. The remaining 527 serum samples were from dry cows. All cattle were vaccinated with B. abortus strain 19 between 3-10 months of age. Five hundred and fifty-two milk samples and 562 serum samples were obtained from 6 infected herds with abortions where B. abortus was isolated at least once no more than 6 months before sampling. The complement-fixation test (CFT) on serum samples was considered the gold standard. Serum samples were also tested with the official screening test: the buffered plate antigen (BPA) test. The cut-off point was determined using receiver-operating characteristic (ROC) analysis. For milk samples, it was fixed at 36 percent positivity (PP) giving a sensitivity of 99.6% with a 95% confidence interval (CI) of 98.6-99.9%. The specificity was 99.1% (CI 98.9-99.4%). For serum samples, the cut-off was fixed at 53 PP giving a sensitivity of 99.6% (CI 98.6-99.9%) and a specificity 98.6% (CI 98-99%). The BPA test showed a relative sensitivity of 99.6% (CI 98.6-99.9%) and a relative specificity of 98.6% (CI 98.1-99%). Our results indicate that the indirect ELISA is a highly sensitive and specific test and can be adapted to process a large number of samples.
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PMID:Evaluation of an indirect ELISA for the diagnosis of bovine brucellosis in milk and serum samples in dairy cattle in Argentina. 978 76

Smooth Brucella strains are classified into three serotypes, i.e., A+M-, A-M+, and A+M+, according to slide agglutination with A and M monospecific polyclonal sera. The epitopes involved have been located on the O-polysaccharide (O-PS) moiety of the smooth lipopolysaccharide (S-LPS), which represents the most exposed antigenic structure on the surface of Brucella spp. By use of monoclonal antibodies (MAbs) a number of epitope specificities on the O-PS have been reported: A, M, and epitopes shared by both A and M dominant strains, which have been named common (C) epitopes. The latter have been further subdivided, according to relative MAb binding in enzyme-linked immunosorbent assays (ELISA) to A- and M-dominant Brucella strains and to cross-reacting Yersinia enterocolitica O:9, into five epitopic specificities: C (M>A), C (M=A), C/Y (M>A), C/Y (M=A), and C/Y (A>M). In the present study, we studied the occurrence of these epitopes at the surface of representatives of all Brucella species and biovars including the live vaccine strains by analyzing the levels of MAb binding to whole Brucella cells in ELISA and flow cytometry assays. In ELISA, the level of MAb binding correlated well with the previously defined epitope specificity and the serotype defined by polyclonal sera for each Brucella species, biovar, or strain. However, MAbs to the C (M=A) and C (M>A) epitopes showed insignificant binding to B. suis biovar 2 strains and bound at lower titers to B. suis biovar 3 and B. neotomae than to the other Brucella strains. Some of the flow cytometry results were contradictory to those obtained by ELISA. In fact, it appeared by flow cytometry that all O-PS epitopes, including the A and M epitopes, are shared to different degrees by Brucella spp. which nevertheless show a high degree of O-PS heterogeneity according to MAb binding intensities. The subdivision of MAb specificities and Brucella serotypes was therefore less evident by flow cytometry than by ELISA. Whereas in ELISA the MAb specific for the A epitope showed insignificant binding to Y. enterocolitica O:9, this MAb bound strongly to Y. enterocolitica O:9 in flow cytometry. One of the two MAbs specific to the C (M=A) epitope also bound at a low but significant level to B. suis biovar 2 strains. However, as in ELISA the MAb specific for the C (M>A) epitope did not bind at all to B. suis biovar 2 strains in flow cytometry. Flow cytometry provided new information regarding specificity of the MAbs and may further explain some aspects of the capacity of passive protection of some MAbs against smooth Brucella infection in mice. As shown in the present study the occurrence of Brucella strains apparently completely devoid of one specific C O-PS epitope (e.g., B. suis biovar 2 devoid of the C [M>A] epitope) offers the possibility of obtaining vaccine strains devoid of a diagnostic O-PS epitope, which could further help to resolve the problem of discriminating infected from vaccinated animals that remains a major goal in brucellosis research.
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PMID:O-Polysaccharide epitopic heterogeneity at the surface of Brucella spp. studied by enzyme-linked immunosorbent assay and flow cytometry. 980 49

The possibility of using brucellar protein antigens with mol. weights of 18 and 38 kD, synthesized in E.coli cells, as sensitins on polystyrene plates in the enzyme immunoassay (EIA) for the detection of antibodies in the blood sera of patients with different forms of brucellosis. The use of antigens with mol. weights of 18 and 38 kD made it possible to detect antibodies in patients with the acute form of the disease in 68.97% and 75.86% of cases, and in patients with the chronic form in 33.3% and 22.9% of cases respectively. The main advantage of using antigen with a mol. weight of 38 kD in EIA was its specificity. Antibodies to heterologous microorganisms (Yersinia enterocolitica O:9) having common antigenic determinants with Brucella were not detected. Still the titers of antibodies isolated with the use of these antigens were lower than those obtained in reactions with B.abortus 99 S-lipopolysaccharide.
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PMID:[Use of Brucellar protein antigen synthesized in Escherichia coli cells in the enzyme immunoassay]. 982 7

A procedure for standardizing Brucella abortus smooth lipopolysaccharide used in diagnostic tests for brucellosis is proposed. The procedure is based on the reactivity of antigen preparations with a panel of sera with or without antibody to B. abortus using a set of parameters established with 13 antigen preparations. For each serum dilution, a mean and two standard deviations were calculated in the indirect and competitive enzyme immunoassays. If data obtained with an antigen preparation, using the same serum dilutions, falls within the range established using two standard deviations, the antigen would be considered acceptable for diagnostic use.
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PMID:Standardization of smooth lipopolysaccharide preparations for use in diagnostic serological tests for bovine antibody Brucella abortus. 984 Feb 96

A sandwich enzyme-linked immunosorbent assay (ELISA) with monoclonal antibody coupled to the solid phase was evaluated for the detection of brucella antigen in serum samples. Under optimum conditions, 100 brucella cells/well or 10(5) fg/ml of lipopolysaccharide (LPS) were detected in spiked specimens. The standardised assay was performed on 1607 sera from random blood donors, 146 patients with brucellosis, 20 persons in high risk groups and 264 sera from patients with diseases other than brucellosis. Sensitivity was 100% compared with positive blood culture, and 44% compared with serological tests for brucella antibodies. Specificity was 99.5% among random blood donors and 99.2% in the patient population. These data showed a strong agreement between ELISA antigen detection and blood culture for the detection of brucella positive blood samples. Moreover, the results indicated that antigen detection by ELISA could be an acceptable alternative to blood culture for the diagnosis of brucellosis.
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PMID:Enzyme-linked immunosorbent assay for brucella antigen detection in human sera. 987 60

Between 1983 and 1996 a total of 1386 samples of serum were taken from four species of seal and three species of whale in the waters west of Iceland, the area of pack-ice north-west of Jan Mayen, the northern coast of Norway and the Kola Peninsula, the waters west of Svalbard, and the Barents Sea; they were tested for the presence of anti-Brucella antibodies with an indirect ELISA (protein G conjugate). The positive sera were re-tested with classical brucellosis serological tests, such as the serum agglutination test, the EDTA-modified serum agglutination test, the Rose Bengal test, and the complement fixation test, as well as an anti-complement ELISA. Anti-Brucella antibodies were detected in all the species investigated, except for the bearded seal (Erignathus barbatus), with the following prevalences: hooded seals (Cystophora cristata) 35 per cent; harp seals (Phoca groenlandica) 2 per cent; ringed seals (Phoca hispida) 10 per cent; minke whales (Balaenoptera acutorostrata) 8 per cent; fin whales (Balaenoptera physalus) 11 per cent; and sei whales (Balaenoptera borealis) 14 per cent. An isolate belonging to the genus Brucella was obtained from the liver and spleen of one of the seropositive minke whales. The findings suggest that antibodies against the surface lipopolysaccharide of Brucella species are widely distributed among marine mammals in the North Atlantic Ocean.
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PMID:Evidence of Brucella infection in marine mammals in the North Atlantic Ocean. 1037 90

The diagnosis of human neurobrucellosis usually relies on the detection of antibodies to Brucella lipopolysaccharide (LPS) in cerebrospinal fluid (CSF) by agglutination tests or enzyme-linked immunosorbent assay (ELISA). Here we describe the detection of immunoglobulin G (IgG) to cytoplasmic proteins (CP) of Brucella spp. by ELISA and Western blotting in seven CSF samples from five patients with neurobrucellosis. While IgG to CP (titers of 200 to 12, 800) and IgG to LPS (800 to 6,400) were found in the CSF of these patients, these antibodies were not detected in CSF samples from two patients who had systemic brucellosis without neurological involvement. The latter, however, had serum IgG and IgM to both LPS and CP. No reactivity to these antigens was found in CSF samples from 14 and 20 patients suffering from nonbrucellar meningitis and noninfectious diseases, respectively. These findings suggest that, in addition to its usefulness in the serological diagnosis of human systemic brucellosis, the ELISA with CP antigen can be used for the specific diagnosis of human neurobrucellosis.
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PMID:Detection of antibodies to Brucella cytoplasmic proteins in the cerebrospinal fluid of patients with neurobrucellosis. 1047 31

The methods commonly used for human brucellosis serological testing are agglutination tests and the complement fixation test (CFT). Among the newer serological tests, primary binding assays were developed to improve sensitivity and specificity. The competitive enzyme immunoassay (CELISA) for the detection of serum antibody to Brucella is a multispecies assay which appears to be capable of differentiating vaccinal and cross-reacting antibodies from antibodies elicited by field infection in cattle. The competing monoclonal antibody used in this assay is specific for a common epitope of smooth lipopolysaccharide (S-LPS). In this study, we compared the CELISA to the classical tests for the diagnosis of human brucellosis. The CELISA cutoff value was determined to calculate its diagnostic specificity and sensitivity. A survey was performed with 911 sera. Of the sera, 341 were from an asymptomatic population that tested negative with conventional serological tests (screening and confirmatory). Based on these samples, the CELISA specificities were determined to be 99.7 and 100% with cutoff values of 28 and 30% inhibition (%I), respectively. In a further study with 393 additional sera from an asymptomatic population found negative by the conventional screening tests, the CELISA specificities were calculated to be 96.5 and 98.8% with cutoff values of 28 and 30%I. The CELISA sensitivities were determined to be 98.3 and 94.8% with cutoff values of 28 and 30%I, respectively, for sera from 116 individuals found positive by the classical tests. For the 51 culture-positive patients, CELISA was positive for 100%, the CFT was positive for 92%, and the standard tube agglutination test (TAT) was positive for 100%. The CELISA specificity was 100% for 31 sera from patients found negative by conventional serological tests but with brucellosis-like symptoms. The CELISA is fairly rapid to perform, somewhat faster than TAT, and cross-reacts less with other antigens (or antibodies) than the conventional tests. Further, the CELISA is simpler to perform that the CFT and may readily be standardized by the use of purified S-LPS antigen and monoclonal antibody for competition.
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PMID:Competitive enzyme immunoassay for diagnosis of human brucellosis. 1048 86


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