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 level of serum IgM, IgG and IgA antibodies including IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2 subclass-specific antibodies to Bacteroides (Porphyromonas) gingivalis fimbriae and to lipopolysaccharide (LPS) were analysed in patients with different forms of periodontal disease (PD) and control subjects by ELISA. Among PD subjects, sera obtained from adult periodontitis (AP), rapidly progressive periodontitis (RPP) and gingivitis contained high titres of fimbriae-specific IgG antibodies (7500-15,000 ELISA units) followed by IgA (90-700 units) and IgM (30-90 units). In contrast, sera from localized juvenile periodontitis (LJP) subjects exhibited much lower titres of fimbriae-specific IgG (89 +/- 11 units), IgA (31 +/- 5 units) and IgM (17 +/- 3 units) antibodies. A similar response pattern was also seen in sera from normal subjects aged 35-41 years who practice normal oral hygiene, while sera of younger adults (aged 18-24) with superior hygiene did not have any antigen-specific antibodies. Analysis of IgG subclass anti-fimbriae responses revealed that the major response was IgG3 followed by IgG1, IgG2 and IgG4 in AP, RPP and gingivitis. Although lower, a similar pattern of IgG subclass titre was seen in LJP and normal subjects aged 35-41 years. When IgA subclass responses were measured in AP and RPP, higher titres of the fimbriae-specific response were noted with IgA1 when compared with IgA2. However, lower but approximately equal levels of fimbriae-specific IgA1 and IgA2 titres were seen in other PD groups. When anti-B. gingivalis LPS-specific responses were measured, the sera of AP patients contained high levels of IgG antibodies (2265 +/- 224 units) followed by IgA (411 +/- 90 units) and IgM (214 +/- 56 units). Further, IgG anti-LPS responses were mainly IgG2 followed by IgG4, IgG3 and IgG1. For IgA subclass responses, higher titres of anti-LPS-specific antibodies were noted in IgA2 subclass over IgA1. These results showed that higher anti-B. gingivalis antibody responses occur in PD when compared with healthy individuals and protein and lipid-carbohydrate antigens of B. gingivalis induce distinct patterns of antigen-specific IgG and IgA subclass responses.
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PMID:Bacteroides gingivalis-specific serum IgG and IgA subclass antibodies in periodontal diseases. 197 4

The short-term kinetics and the effects of different dose regimens and formulations on the humoral immune response induced in human subjects by the live attenuated typhoid vaccine Salmonella typhi Ty21a were examined. Antibody responses in jejunal fluid and serum and by specific antibody production in vitro by peripheral blood lymphocytes to S. typhi lipopolysaccharide were determined. A short vaccination schedule of three doses of 10(11) live organisms over 5 days induced significantly greater intestinal IgA antityphoid antibody responses than did two comparable doses 21 days apart. The humoral immune response was dose dependent with 10(10) and 10(11) live organisms stimulating greater intestinal immune responses than did 10(11) killed organisms. No responses were evident with either 10(9) viable organisms or with an enteric-coated preparation. In the continued development and assessment of oral typhoid vaccines, the effects of different doses and formulations and the timing of sampling on the humoral immune response should be considered.
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PMID:The human humoral immune response to Salmonella typhi Ty21a. 198 18

Under endotoxin-free conditions, peripheral blood mononuclear cells and purified monocytes isolated from healthy control subjects and patients with alcoholic cirrhosis disclose elevated tumor necrosis factor alpha messenger RNA level and produce tumor necrosis factor alpha in response to stimulation by either soluble polymeric IgA or monomeric IgA bound to the surface of culture dishes but not by soluble monomeric IgA. Polymeric IgA induces tumor necrosis factor alpha secretion in a dose-dependent fashion. These results suggest that cross-linking of Fc alpha receptors on human monocytes induces the messenger RNA accumulation and the secretion of the cytotoxic and immunoregulatory cytokine tumor necrosis factor alpha. Furthermore, it is shown that lipopolysaccharide-induced tumor necrosis factor alpha secretion by peripheral blood mononuclear cells is synergistically enhanced in the presence of solid phase monomeric IgA but not in the presence of either soluble monomeric or polymeric IgA. Although increased lipopolysaccharide-induced tumor necrosis factor alpha secretion is observed at baseline in alcoholic cirrhotic patients, this synergism is also expressed in this group of patients. These observations could be of pathophysiological relevance in alcoholic cirrhosis because monomeric IgA deposits along the liver sinusoids and increased serum levels of polymeric IgA are common even in the early stages of this disease.
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PMID:IgA triggers tumor necrosis factor alpha secretion by monocytes: a study in normal subjects and patients with alcoholic cirrhosis. 201 Jan 62

Polyclonal B cell activation (PBA) and autoimmune disease can be induced in immunologically normal mice, or enhanced in lupus-prone mice, by bacterial lipopolysaccharide (LPS). Because immune defects are common in autoimmune diseases and IgA deficiency is prevalent in patients with systemic lupus erythematosus, we investigated: (i) whether LPS might induce IgA deficiency in normal mice; (ii) whether IgA deficiency might be a feature in lupus-prone mice; (iii) whether, if present in lupus-prone mice, IgA deficiency could be further accentuated by LPS; and (iv) whether the effects of LPS on IgA concentrations of normal and lupus-prone mice might be reversible upon withdrawal of LPS. We injected normal (C57BL/6) and lupus-prone (NZB/W) mice with 50 micrograms of LPS from Salmonella minnesota Re595 twice a week for 5 weeks and then discontinued LPS for 6 weeks. We determined the concentrations of plasma immunoglobulins, DNA antibodies, and circulating immune complexes before, during, and after mice were exposed to LPS. Our results indicate that: (i) LPS induces IgA deficiency in normal mice concurrently with PBA; (ii) IgA deficiency is a feature of lupus-prone mice; (iii) LPS accentuates naturally occurring PBA and IgA deficiency in lupus-prone mice; and (iv) LPS induced, or LPS enhanced, IgA deficiency and PBA in normal and lupus-prone mice persist long after withdrawal of LPS. Thus, LPS triggers or enhances autoimmune disease by a mechanism that involves in part PBA with selective increase (IgG, IgM) and concurrent decrease (IgA) of specific isotypes.
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PMID:Bacterial lipopolysaccharide induces long-lasting IgA deficiency concurrently with features of polyclonal B cell activation in normal and in lupus-prone mice. 201 4

This study was designed to (i) delineate the characteristics of serum antibody responses to Actinobacillus actinomycetemcomitans in patients with periodontitis who are infected with A. actinomycetemcomitans; irrespective of disease classification; (ii) assess the relationship of the elevated antibody levels to colonization of the oral cavity by A. actinomycetemcomitans; and (iii) describe the serotype distribution of A. actinomycetemcomitans and antibodies to the microorganism in infected patients with various clinical classifications. To compare the levels of various isotype-specific antibodies to the different antigens, studies were performed that allowed quantitation of each isotype-specific antibody in a human reference standard. By using this reference standard, it was shown that the levels of immunoglobulin G (IgG), IgM, and IgA responses to A. actinomycetemcomitans were similar among the infected patients, irrespective of disease classification. Also, we demonstrated that the serum antibody response to serotype b was quantitatively greater in all isotypes. Our findings indicate that b was the most frequent A. actinomycetemcomitans serotype detected in the patients and appears to be capable of initiating a substantial serum IgG antibody response that may contain cross-reactive antibodies to other serotypes of A. actinomycetemcomitans. Generally, in cases in which the response to a single serotype was elevated, only that type of A. actinomycetemcomitans was detected in the plaque. Individuals exhibiting elevated antibodies to multiple serotypes were most consistently colonized by the serotype b microorganism. This study represents the first report detailing the distribution of IgG subclass antibodies to A. actinomycetemcomitans in periodontal disease. The results demonstrated that the primary responses of patients with periodontitis to A. actinomycetemcomitans were of the IgG1 and IgG3 subclasses, which is consistent with elicited responses to protein antigens. In contrast, the primary subclass response in normal subjects was limited to the IgG2 subclass and may represent broader cross-reactivity to polysaccharide antigens-lipopolysaccharide from the bacteria.
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PMID:Serum antibody in Actinobacillus actinomycetemcomitans-infected patients with periodontal disease. 201 43

A rat fetal intestinal transplant model was developed for long-term study of intestinal immune responses. For the model, fetal small intestine is transplanted into the dorsal subcutaneous tissue of syngeneic adults and allowed to mature, providing an accessible site, isolated from the intestinal stream. We previously demonstrated normal histologic maturation of the transplant. Specific antibody-producing cells appeared in the lamina propria of both transplant and native in situ intestine following intraluminal immunization of the transplant with cholera toxin, and conversely, in transplants after immunization of in situ intestine. An enterointestinal lymphocyte migratory pathway (originating in intestine and migrating to another region of the intestine) was thus demonstrated unequivocally. We found a bacterial flora in the transplant, and showed normal villus morphology in scanning electron microscopy. Less than 200 pg, i.e., a 10(-7) fraction, of 2 mg macromolecular lipopolysaccharide placed in the transplant lumen was absorbed per plasma lipopolysaccharide half-life. Immunization of the transplant with cholera toxin resulted in specific IgA and IgG antibody in the transplant lumen and in bile, and specific IgG, but not IgA, antibody in serum. A second dose of antigen gave an anamnestic rise in intra-transplant antibody. Intestinal immune tolerance was also demonstrated: sheep red blood cells (SRBC) administered into the transplant for 7 days suppressed splenic IgM plaque forming responses to subsequent intraperitoneal challenge with SRBC. These studies further demonstrate that the fetal intestinal transplant behaves immunologically like native intestine, and therefore provides a useful model for investigation of the intestinal immune system.
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PMID:Fetal intestinal transplant model for mucosal immune responses. 203 72

The performance of enzyme immunoassays (EIAs) with use of O-antigen-containing lipopolysaccharides (LPSs) extracted with phenol-water from Shigella dysenteriae type 1, Shigella flexneri serotypes 1a-5b, and Shigella sonnei for determination of the serum antibody responses after onset of bacillary dysentery is reviewed. For the purpose of several studies, serum samples from a total of 175 Vietnamese and 47 Swedish patients, for whom Shigella species had been isolated from fecal specimens, were obtained at various intervals until less than or equal to 1 year after the onset of infection. Titers of antibodies in serum samples from infected patients were compared with those in serum samples from healthy control subjects; the combined control population of all studies comprised 426 Vietnamese and 154 Swedes. The sensitivity of the EIAs ranged from 78% to 100% for patients whose fecal culture was positive for Shigella. For diagnosis of S. flexneri, a species-specific but no serotype-specific assay based on LPS antigens is possible. Among Vietnamese patients the EIA with use of S. flexneri was sensitive and diagnostic only for children less than 3 years of age, most likely because healthy older Vietnamese children and adults have high titers of antibody to the O-antigens of S. flexneri. Among Swedish patients the same EIA was diagnostic for adults as well as children. Increased titers of IgA in the early phase and of IgG in the convalescent phase, as determined by EIA, were the best indicators of infection due to Shigella species.
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PMID:Shigellosis in Vietnam: seroepidemiologic studies with use of lipopolysaccharide antigens in enzyme immunoassays. 204 43

Shigellosis is a major cause of infant morbidity and mortality in developing countries. To find immunological correlates of specific protection against shigellosis, we examined chronological samples of sera, stool extracts, duodenal aspirates, and saliva samples from 39 adults and 22 children with shigellosis from Peru for the presence of specific antibody to invasion plasmid antigens (Ipa) common to all virulent Shigella strains, by using both a whole-organism enzyme-linked immunosorbent assay (ELISA) and a Western blot (immunoblot) assay. Antibody responses to lipopolysaccharide (LPS) from Shigella serotypes both homologous and heterologous to the infecting strain were also determined by ELISA. ELISAs showed that the highest serum immunoglobulin G (IgG) antibody titers to Shigella whole organisms both with and without surface Ipa were found in adults and malnourished children, the two groups with the shortest and longest durations of disease, respectively. Mucosal IgA antibody titers to Shigella strains decreased over time to a much greater extent than serum IgG titers, and IgA to Ipa in mucosal secretions was found in adults and well-nourished children but not in malnourished children. The presence of mucosal antibody to Ipa may limit the spread and severity of the infection, as indicated by the prolonged illness observed in malnourished children who have no significant mucosal antibody to Shigella Ipa. Serum antibody titers to the Ipa antigens were high relative to anti-Shigella LPS antibody titers, especially in pediatric patients. In contrast to the anti-Ipa responses observed, no differences in antibody responses to LPS in children compared by nutritional status were found. High levels of serum and mucosal cross-reacting antibody to heterologous serotype LPS were found between Shigella flexneri serotypes 1a and 2a. Different patterns of immune response to Ipa proteins and LPS that may aid in the definition of Shigella antigens important in host protection were observed in adults, well-nourished children, and malnourished children.
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PMID:Prospective study of systemic and mucosal immune responses in dysenteric patients to specific Shigella invasion plasmid antigens and lipopolysaccharides. 205 Apr 2

Oral immunization with a delta cya delta crp Salmonella typhimurium strain has been shown to preclude colonization by wild-type, virulent S. typhimurium and induces humoral and cellular immune response in chickens. Intestinal tract colonization by the virulent challenge strain was used to determine the level of protection conferred by immunization with the delta cya delta crp mutant. The associated humoral and cellular immune responses were measured by ELISA and delayed-type hypersensitivity (DTH) tests, respectively. The levels of colonization by both Salmonella strains were determined by enumeration of viable cells in the intestinal tract. A reduction in faecal excretion of the wild-type strain was observed with a single oral immunization with the delta cya delta crp mutant, but caecal colonization was not affected. However, double oral immunization with the delta cya delta crp mutant precludes caecal colonization by the virulent strain. IgM, IgA and IgG were detected against sonicated Salmonella whole-cell antigens. Outer membrane and flagella proteins induced DTH responses, whereas lipopolysaccharide failed to do so. The effectiveness of the delta cya delta crp strain in reducing caecal colonization by the highly virulent challenge strain in chickens demonstrates that oral vaccination with the delta cya delta crp S. typhimurium should aid in eliminating Salmonella carriers in chickens. The elimination of these carriers on the poultry farm should help to control Salmonella contamination of poultry products, therapy improving public health.
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PMID:Control of colonization by virulent Salmonella typhimurium by oral immunization of chickens with avirulent delta cya delta crp S. typhimurium. 210 73

Peripheral blood B-lymphocyte markers and functions were observed in 21 patients with IgA nephropathy (IgA NP) and in 16 controls. IgA NP B lymphocytes expressed significantly higher positivity with Leu 1 (CD 5) monoclonal antibody than controls. CD 5 positive B lymphocytes are thought to be a distinct subset of the B cells (autoregulatory B lymphocytes) inducible in IgA NP by lipopolysaccharide (LPS) stimulation parallel to the higher expression of surface IgM heavy chain positivity. The activated state of IgA NP B lymphocytes has been proved by their higher OKIa (HLA-DR) positivities but lower IOB1a (CD 21, C3d-receptor) and decreased IgG-Fc-receptor (ox-rosette) expression. IgA NP B lymphocytes showed a higher IgA but also IgG and IgM polyclonal immunoglobulin production than control B lymphocytes in co-cultures with T lymphocytes. Not only regulatory T lymphocyte subsets but also serum derived from IgA NP patients stimulated the immunoglobulin production of IgA NP B cells.
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PMID:Peripheral B-lymphocyte markers and function in IgA nephropathy. 210 34


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