Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An immune dot blot test (IDBT) to detect the genus specific lipopolysaccharide chlamydial antigen is described, in which the antigen is trapped on nitrocellulose membrane and then detected with a monoclonal antibody labelled with 125iodine. A preliminary comparison of 270 specimens obtained from the endocervix or male urethra showed that the IDBT was more sensitive (sensitivity 90%) than a commercial amplified enzyme immunoassay named IDEIA (sensitivity (60%) for detecting specimens that yielded Chlamydia trachomatis on culture. Subsequent assessment of 950 urogenital tract specimens in the IDBT and by culture confirmed the sensitivity (92%) and specificity (95%) of the IDBT. At least one of 56 specimens obtained from the eye, however, gave a false positive result, which was probably due to staphylococcal protein A in the specimen. The IDBT provides the basis for a novel simple test for detecting the genus Chlamydia.
 ...
PMID:Immune dot blot technique for diagnosing infection with Chlamydia trachomatis. 342 94

In this study, we examined the temporal antibody response by immunoblotting analysis in tears and sera of three cynomolgus monkeys (Macaca fasicularis) with primary acute Chlamydia trachomatis serovar B conjunctivitis. The objective was to identify chlamydial antigens stimulating antibody during the host responses in the course of this self-limiting infection with the rationale that they may be protective antigens. The major outer membrane protein (MOMP), lipopolysaccharide (LPS), and polypeptides of 60 and 68 kilodaltons (kDa) were the predominant antigens recognized by immunoglobulin A (IgA) in monkey tears. Tear IgA antibody specific for the MOMP was first detected 14 days postinfection, whereas tear IgA reactive with LPS or the 68- and 60-kDa polypeptides was first detectable on day 21. Tear IgA antibodies specific for each of these antigens persisted in tears through day 56, 4 weeks after both peak clinical disease and recovery of the organism from the conjunctivae. In contrast, tear IgG antibodies peaked at approximately 28 days postinfection, the time of maximal inflammatory response. The IgG response in monkey sera was similar to that observed for tear antibodies, in that the MOMP, 60-, and 68-kDa polypeptides were the primary immunogens. The exception was that IgG antibody against these antigens was detected 1 week later than that observed for tear IgA antibodies. Of three monkeys that responded with tear IgA antibody against LPS, one did not have detectable serum IgG LPS antibody. The specificity of the tear IgA antibody response of monkeys was determined by immunoblotting nine other C. trachomatis serovars in addition to the homologous B serovar. The tear IgA response to the MOMP was predominantly B complex subspecies-specific (serovars B, Ba, D, and E), whereas the response to chlamydial LPS was found to be species-specific. The significance of these observations in relation to previous vaccine studies in nonhuman primates is discussed.
 ...
PMID:Tear and serum antibody response to Chlamydia trachomatis antigens during acute chlamydial conjunctivitis in monkeys as determined by immunoblotting. 353 9

A panel of monoclonal antibodies (MAb) was generated against Chlamydia trachomatis serovar B, an etiologic agent of blinding trachoma. The specificities of MAb were determined by dot blot assay by using viable elementary bodies of 13 C. trachomatis serovars and two C. psittaci strains. The dot blot assay was used to identify those antigens that were unique and immunoaccessible on the chlamydial surface. MAb were identified that recognized bi-specific (serovars B and Ba) or subspecies-specific (various B complex serovars) surface-exposed antigenic determinants that were either resistant or sensitive to heat denaturation (56 degrees C, 30 min). All of the MAb recognized the major outer membrane protein as determined by either immunoblotting or radioimmunoprecipitation. MAb specific for immunoaccessible major outer membrane protein epitopes protected mice from toxic death after i.v. injection of B serovar elementary bodies and neutralized the infectivity of the organism for monkey eyes. In contrast, MAb reactive against non-immunoaccessible subspecies- or species-specific major outer membrane protein epitopes or against an immunoaccessible genus-specific epitope located on chlamydial lipopolysaccharide did not protect mice from toxic death or neutralize infectivity of the parasite for monkey eyes. These data suggest that those major outer membrane protein antigenic determinants that are serovar or serogroup specific and are accessible to antibody on the chlamydial cell surface may be useful as a recombinant subunit vaccine for trachoma.
 ...
PMID:Protective monoclonal antibodies recognize epitopes located on the major outer membrane protein of Chlamydia trachomatis. 354 Jan 22

Active trachoma is characterized by chronic inflammation of the conjunctiva, and repeated episodes of reinfection are thought to be necessary to sustain this inflammation. It is currently believed that much of the tissue damage is immunologically mediated. To identify which antigens might be responsible for stimulating this continued inflammation, cynomolgus monkeys that had recovered from a previous ocular infection with Chlamydia trachomatis were challenged with various antigen preparations. Purified preparations of formalin- or UV-inactivated elementary bodies did not elicit any inflammation even with daily inoculation. In addition, neither purified chlamydial major outer membrane protein nor lipopolysaccharide, including recombinant organisms expressing the lipopolysaccharide group antigen, elicit inflammation. A soluble triton extract of the organism rapidly induced marked inflammation when inoculated in the eyes of immune monkeys but had no effect in naive animals. These studies suggest that the continual inflammation in trachoma may not be due to repeated exposure to chlamydial surface antigen(s) but rather to a labile product released by the living organisms.
 ...
PMID:Pathogenesis of trachoma: the stimulus for inflammation. 357 82

Studies using the guinea pig model of chlamydial genital infection with the Chlamydia psittaci agent of guinea pig inclusion conjunctivitis (GPIC) have shown that serum and local antibodies play a role both in the resolution of infection and in protection against reinfection. Thus, this model is suited for further exploration of immune mechanisms and for vaccine studies with chlamydial macromolecules. We have further characterized the model by assessing the antigen-specific antibody response to experimental genital infection by using immunoblotting to assay both genital secretions and serum. The GPIC agent was characterized by analysis of outer membrane proteins, which indicated that the GPIC agent possessed a major outer membrane protein (MOMP), with a molecular mass of 39 kilodaltons (kDa), and a 61-kDa protein, analogous to cysteine-rich 60-kDa proteins or doublets of Chlamydia trachomatis strains. As indicated by immunoblotting, most infected animals produced serum immunoglobulin G antibodies to MOMP, the 61-kDa proteins, an 84-kDa outer membrane protein, and lipopolysaccharide. Such serum antibodies persisted for at least 813 days after primary genital infection. Immunoglobulin A antibodies against the 61-kDa proteins, lipopolysaccharide, and MOMP, but not the 84-kDa protein, were detected in secretions. Animals challenged with GPIC 825 days after primary infection became infected again despite the presence of serum antibodies, but the period of chlamydial shedding was significantly shorter and less intense than in primary infections. Although the specific mechanism is not known, these data suggest that a long-lasting immune effect is capable of altering the course of infection late after primary infection. Correlation of the antigen-specific antibody response and other immune parameters with the duration and degree of protective immunity induced by infection or vaccination may be helpful in further understanding the nature of such protective immunity.
 ...
PMID:Analysis of the humoral immune response to chlamydial genital infection in guinea pigs. 361 Mar 14

A total of 77 Chlamydia psittaci strains of avian, human, and mammalian origin were grouped into four serovars with 11 monoclonal antibodies recognizing the lipopolysaccharide and the major outer membrane protein antigens. The avian and human strains, which were closely related to each other, were distinct from the mammalian strains. Immunological typing of C. psittaci with monoclonal antibodies seems practical.
 ...
PMID:Monoclonal antibody typing of Chlamydia psittaci strains derived from avian and mammalian species. 366 18

The lipopolysaccharide (LPS) of Chlamydia psittaci was extracted from yolk sac-grown elementary bodies, purified, and characterized chemically, immunochemically, and biologically. The LPS contained D-galactosamine, D-glucosamine, phosphorus, long-chain fatty acids, and 3-deoxy-D-manno-2-octulosonic acid in the molar ratio of approximately 1:2:2:6:5. The antigenic properties of the isolated LPS were compared with those of the LPS from Chlamydia trachomatis and Salmonella minnesota Re by the passive hemolysis and passive hemolysis inhibition tests, absorption, hydrolysis kinetics, and Western blot analysis with rabbit polyclonal antisera against chlamydiae and with a mouse monoclonal antibody recognizing a genus-specific epitope of chlamydial LPS. Two antigenic determinants were identified, one of which was chlamydia specific and the other of which was cross-reactive with Re LPS. Both determinants were destroyed during acid hydrolysis, whereby a third antigen specificity was exposed which was indistinguishable from the lipid A antigenicity. In rabbit polyclonal antisera prepared against Formalin-killed elementary bodies or detergent-solubilized membranes, two antibody specificities were differentiated. One of these was chlamydia specific, and the other was cross-reactive with Re LPS. The LPS of C. psittaci was inactive within typical endotoxin parameters (lethal toxicity, pyrogenicity, local Shwartzman reactivity); it was, however, active in some in vitro assays, such as those testing for mouse B-cell mitogenicity and the induction of prostaglandin E2 in mouse peritoneal macrophages.
 ...
PMID:Chemical, biological, and immunochemical properties of the Chlamydia psittaci lipopolysaccharide. 377 Sep 53

The value of several serological tests was assessed by studying sera from 30 women with clinical findings of perihepatitis and a high chlamydial antibody titre in the indirect immunofluorescence antibody test (IFAT). The other tests included the complement fixation test and enzyme immunoassays in which the antigen comprised either partially purified particles (EIA kit) or purified major outer membrane protein (MOMP EIA) of Chlamydia trachomatis L2 or lipopolysaccharide isolated from an Re mutant of Salmonella (Re LPS EIA). High IgG titres were noted in most (88-96%) of the patients by MOMP EIA and EIA kit, and in fewer patients (50%) by Re LPS EIA or complement fixation test. Seroconversion was found in 11-44% of the patients for IgG and in 28-36% for IgM; high IgG titre was thus the best diagnostic indicator for each test. The enzyme immunoassay tests have the advantage of being automated either with partially purified corpuscular or purified MOMP antigen and would allow a sensitive easy screening for chlamydial aetiology of women with pain of the right upper quadrant.
 ...
PMID:Comparative sensitivity of different serological tests for detecting chlamydial antibodies in perihepatitis. 389 92

The chlamydial genus-specific antigen was extracted with phenol/chloroform/petroleum ether (PCP) from preparations of Chlamydia trachomatis and C. psittaci, and quantities measured using an assay for lipopolysaccharide (LPS). The LPS from C. trachomatis contained 2.2% (w/w) of ketodeoxyoctanoic acid. Five IgG monoclonal antibodies reacted in an ELISA with LPS from both species, the antigen being periodate-sensitive and heat-resistant, confirming that all antibodies were against the genus-specific antigen. All the antibodies bound to the PCP extract of C. trachomatis on an immunoblot, at a position corresponding to the periodate-Schiff-stained bands of both C. trachomatis extract and Salmonella Re-LPS. When linked to trypsin-treated sheep erthrocytes and used in reverse passive haemagglutination tests, all antibodies gave indicator cells capable of detecting chlamydial LPS or crude preparations of chlamydiae grown in McCoy cells, the sensitivity varying with the antibody used. The antibodies varied in IgG subclass (either IgG2a or IgG3), and in ability to precipitate in immunodiffusion tests. Two antibodies cross-reacted with one strain of Acinetobacter in ELISA and with Salmonella Re-LPS in both ELISA and immunodiffusion tests. The other three did not react in ELISA with Acinetobacter strains or Salmonella Re-LPS, and none of the five reacted with LPS of E. coli or Pseudomonas morsprunorum.
 ...
PMID:Properties of monoclonal antibodies to the genus-specific antigen of Chlamydia and their use for antigen detection by reverse passive haemagglutination. 392 56

The group-specific antigen of Chlamydia trachomatis serotype L2 was chemically analyzed. It is composed of typical lipopolysaccharide (LPS) components, i.e., D-glucosamine, long-chain 3-hydroxy fatty acids, 2-keto-3-deoxyoctonic acid, and phosphate in a molar ratio of approximately 2:5:3:2.6, respectively, resembling enterobacterial LPS of the Re chemotype. For the first time, 3-hydroxydocosanoic acid (3-OH C22:0) was found as an LPS constituent.
 ...
PMID:Chemical characterization of Chlamydia trachomatis lipopolysaccharide. 398 47


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>