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Query: UMLS:C0519030 (Klebsiella)
 21,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Various aspects of pathogenesis, or more broadly, aetiopathogenesis, in the field of B27 related disorders are considered. The main conclusions can be expressed as follows: Genetic factors are involved in the causation of the spondarthritides, although there is still controversy within individual disorders concerning the precise mode of inheritance. For instance, in some conditions evidence appears stronger for a Mendelian mechanism, in others for a multifactorial process. The mode of the HLA-B27-receptor interaction is not yet fully established, but there is strong support for the one gene cross-tolerance theory, in ankylosing spondylitis at least. It is likely that environmental factors 'collaborate' with genetic factors in causing spondarthritic disease. The factors in the environment have yet to be proved, but there is some evidence that micro-organisms such as Klebsiella and Yersinia are involved (e.g. ankylosing spondylitis, Reiter's disease, reactive arthritis). Of noninfective environmental factors, trauma could play a part, as suggested by the mode of onset and pattern of development of some examples of ankylosing spondylitis and psoriatic arthritis.
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PMID:Pathogenetic mechanisms in B27 associated diseases. 641 60

The concept of seronegative spondarthritis, linking several diseases around ankylosing spondylitis, has received considerable clinical and genetic support, especially through the discovery of a high frequency of HLA-B27 in these disorders. Exogenous factors would appear to be responsible for some manifestations of the disease, but the role of Klebsiella micro-organisms is equivocal, and dietary control does not affect clinical manifestations. Increased serum and salivary IgA antibodies in active ankylosing spondylitis patients tend to suggest that IgA may act as an acute-phase reactant.
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PMID:Pathogenesis of seronegative arthritis. 660 73

Total serum immunoglobulins and class specific serum antibodies to Klebsiella pneumoniae, Salmonella typhimurium, Yersinia enterocolitica and Pseudomonas aeruginosa were measured in 107 patients with ankylosing spondylitis (AS) and 110 healthy tissue typed controls by enzyme linked immunosorbent assay (ELISA). The specificity of this technique was confirmed by the use of specific bacterial murine antisera and by cross-absorption of human sera by specific bacteria. Total serum IgA in AS patients correlated with both erythrocyte sedimentation rate (ESR) (P less than 0.001) and C-reactive protein (P less than 0.05) and was significantly elevated compared to healthy individuals (P less than 0.001). A significant elevation of IgA antibodies to K. pneumoniae was detected in the serum of AS patients with active disease when compared to healthy controls (P less than 0.01). These studies support the involvement of an enterobacterial micro-organism in the pathogenesis of AS and further relate to the role of HLA-B27 in this disease.
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PMID:HLA-B27 and the immune response to enterobacterial antigens in ankylosing spondylitis. 660 43

Cultured skin fibroblasts of HLA-B27-positive clinically normal individuals specifically bind, and are modified by, a factor in the culture filtrate of some Klebsiella isolates. These modified fibroblasts are serologically similar to the cells (lymphocytes and fibroblasts) of B27-positive patients with ankylosing spondylitis (B27+AS+). By contrast, B27+AS+ cells fail to bind the factor, presumably because a receptor present on B27+AS- cells has already been blocked or modified by a Klebsiella antigen in vivo.
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PMID:A factor in the culture filtrate of some Klebsiella isolates specifically modifies the fibroblasts of HLA-B27-positive normal individuals. 661 Jun 33

A monoclonal antibody that binds specifically to HLA-B27, B7, and B22 is described. Binding to B27 appeared to be slightly stronger than to B7 and stronger than to B22 in an indirect binding assay, but no difference in B7 and B27 binding could be detected by Scatchard analysis. No distinction could be made between B27 on cells from normal and from ankylosing spondylitis patients in any assay system. The antibody, which was not cytotoxic, blocked complement-dependent cytolysis mediated by human HLA typing sera specific for B7 and B27. Competitive binding studies with other monoclonal antibodies showed that ME1 could block the binding of antibodies that recognized different antigenic sites on HLA. ME1 did not bind to Klebsiella pneumoniae. This reagent will be useful in further analysis of the relationship between B27 and ankylosing spondylitis.
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PMID:Recognition of HLA-B27 and related antigen by a monoclonal antibody. 698 36

Klebsiella organisms have been reported in postoperative endophthalmitis. We describe an experimental model of endophthalmitis with anterior segment inflammation over the injection of Klebsiella oxytoca into the rabbit vitreous. Within 24 hours, polymorphonuclear leukocytes were found at the corneal limbus, adjacent to the endothelium, in the iris and ciliary body, throughout the vitreous, and in the optic nerve. Retinal photoreceptor degeneration was widespread within 48 hours. Mononuclear cells appeared in the vitreous within 72 hours. Increased pathologic manifestations concomitant with decreased numbers of recoverable, viable organisms implicate the endotoxins of K oxytoca in the observed pathologic condition. Our model may be useful in further studies on antibiotic therapy in Klebsiella ocular infections and in continuing work on the cross-reaction between Klebsiella and HLA-B27.
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PMID:Experimental Klebsiella-induced endophthalmitis in the rabbit. 698 40

Acute anterior uveitis (AAU) is a disease of unknown etiology, although it is frequently associated with various autoimmune diseases. It has recently been shown in patients with ankylosing spondylitis (AS), a disease often associated with AAU, that antiserum raised against a particular isolate of Klebsiella pneumoniae would cross-react with lymphocytes possessing HLA-B27. The present study was performed to evaluate the response of lymphocytes of patients to K. pneumoniae and to determine the correlation with HLA-B27. The circulating immune complex levels in the serum of the patients were also determined for correlation with the presence of HLA-B27 antigen. We were able to demonstrate this cross-reactivity in the samples of AAU patients; however, we did find an increased immune complex level that was independent of HLA-B27 antigen. From our results, we conclude that although AAU is clinically associated with AS, the role of K. pneumoniae in these disease states remains unclear.
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PMID:HLA-B27, Klebsiella pneumoniae, and the relation to acute anterior uveitis. 703 95

Although the strong association of HLA-B27 with ankylosing spondylitis (AS) is well documented, the significance of this association is largely unknown. It has recently been reported that Klebsiella pneumoniae was present in the faeces of patients with AS more frequently than in healthy individuals, and that there appeared to be some cross-reactivity between HLA-B27 and Klebsiella. We have therefore attempted to gain an insight into the possible role of Klebsiella in the pathogenesis of AS. The results presented here indicate that HLA-B27 positive individuals with AS have a significantly lower in vitro lymphocyte responsiveness to Klebsiella antigens, as compared with B27 positive and B27 negative healthy controls. By contrast, B27 positive patients with AS as well as B27 positive and negative controls respond equally well to phytohaemagglutinin, Staphylococcus, Streptococcus, Yersinia and Shigella. To investigate a possible cross-reactivity between Klebsiella and HLA-B27, antisera were raised in rabbits against various isolates of Klebsiella. An antiserum to one isolate (427) of Klebsiella lysed the lymphocytes of B27 positive AS patients but not of B27 positive or B27 negative controls. These observations strongly suggest that some Klebsiella antigens cross-react with a gene product closely associated with HLA-B27 or possibly with a modified B27 antigen in patients with AS.
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PMID:The role of Klebsiella in the pathogenesis of ankylosing spondylitis. II Evidence for a specific B27-associated marker on the lymphocytes of patients with ankylosing spondylitis. 738 24

Ankylosing spondylitis and reactive arthritis are seronegative spondyloarthropathies, which are strongly associated with HLA-B27. Despite intensive investigation, the basis for this association is not clear. However, in recent years one favored hypothesis to explain this linkage has been that of molecular mimicry, i.e., sharing of linear or conformational epitopes common to microbial antigens and host structures. During the past few years several examples of molecular mimicry between HLA-B27 and microbial antigens have been described. Heat shock proteins, among others, have been considered as target candidates for autoimmune phenomena, because of the high degree of homology between bacterial and mammalian species. Reactive arthritis triggered by Yersinia or Salmonella provides a unique model for studying the pathogenetic mechanisms underlying human inflammatory joint diseases in general, because the arthritogenic microbes are known and well-characterized. We have described two bacterial proteins that share amino acid homology with HLA-B27, namely YadA (Yersinia adhesin) and OmpH, outer surface proteins of Yersinia and Salmonella, respectively. Notably, the area of identity of these amino acid sequences is located in the same place on the HLA-B27 molecule as a hexapeptide identical between Klebsiella nitrogenase and HLA-B27, and a pentapeptide shared by a Shigella flexneri protein and HLA-B27. We have investigated immune responses to a panel of synthetic peptides based on the HLA-B27-homologous portions of pathogen-specific antigens in patients with reactive arthritis and ankylosing spondylitis. One third of the patients have antibodies to the synthetic peptides. However, instead of recognizing the HLA-B27-homologous portion, the antibodies are directed against the flanking sequences of the synthetic peptides. The concept of the role of molecular mimicry between HLA-B27 and microbial antigens in the pathogenesis of spondyloarthropathies is discussed, with a conclusion that no convincing evidence for its significance exists at the present.
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PMID:Molecular mimicry: any role in the pathogenesis of spondyloarthropathies? 750 16

This study was performed in order to probe the possible pathogenesis of Klebsiella pneumoniae (KP) in ankylosing spondylitis (AS). 34 anti-KP antibody positive serum samples, including 26 patients with AS, 5 patients with rheumatoid arthritis (RA) and 2 healthy individuals, were selected to detect anti-subtypical KP antibodies by using an immunoblotting technique. The results showed that the number of antigenic bands to KP on nitrocellulose membrane was higher in AS patients than in RA patients and healthy individuals. Patients with AS had common antibodies response to KP components weight 64,600 (80.7%), 48,200 (61.5%) and 36,000 (65.4%), patients with RA and healthy individuals had anti-36,000 (75%) and anti-30,000 (50%) antibodies. Human anti-HLA-B27 serum and rabbit antisera against KP-derived synthetic peptide containing the hexapeptide sequence shared by HLA-B27 were able to cross react with 64,600 and 48,200 KP components. Our findings suggest that KP might play a role in the pathogenesis of AS by molecular mimicry between it and HLA-B27.
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PMID:[Serum anti-subtypical Klebsiella pneumoniae antibodies in ankylosing spondylitis]. 764 43


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