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

The three-dimensional structure of the HLA class I molecules has highlighted the importance of the "groove" formed by the helices. We used site-directed mutagenesis to construct a series of HLA-B27 mutants with different substitutions at the sites of the conserved amino acid residues of HLA-B27 subtypes, specifically residue 77 which is thought to be critical to the binding site of the molecule, and a residue at the CD8 binding site. We formed an anti-B27 CTL line and derived six anti-B27 clones. Each of the six clones showed a different pattern of reaction, reflecting the diversity of the epitopes recognized. All nine mutants were effective in altering allorecognition by HLA-B27 specific CTL, although positions 45 and 77 caused the most drastic effect. The residue in position 77 is also the last amino acid of the peptide sequence shared with Klebsiella. Our results highlight the importance of certain epitopes in allorecognition that may have important implications for the immunotherapy of autoimmune diseases.
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PMID:Effect of the substitution of critical residues on the allorecognition of HLA-B27. 128 53

Only 3 cases of isolated septic arthritis of a lumbar facet joint have been reported, all due to Staphylococcus aureus. We describe a case of Klebsiella pneumoniae septic arthritis of a lumbar facet joint in an HLA-B27 positive patient.
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PMID:Klebsiella pneumoniae septic arthritis of a lumbar facet joint. 149 10

We describe an amino acid homology between a virulence plasmid encoded outer membrane protein of Yersinia, YadA (previously called Yop1) and HLA-B27. This tetrapeptide is also included in the hexapeptide, earlier found to be identical between Klebsiella nitrogenase and HLA-B27. The synthetic peptide based on the HLA-B27 homologous portion of the YadA does not stimulate lymphocytes obtained from HLA-B27+ patients with Yersinia-triggered reactive arthritis or from controls. One-third of the yersiniosis patients have antibodies against the synthetic peptide. Instead of recognizing the HLA-B27 homologous portion, the antibodies are directed against the left flanking sequence of the synthetic peptide. Similar results were obtained regarding antibody response to Klebsiella nitrogenase derived synthetic peptide included in the panel of controls; the response was not restricted to patients with reactive arthritis nor was it specifically directed against the sequence shared by HLA-B27 and Klebsiella pneumoniae nitrogenase. The present results do not support the role of molecular mimicry or cross-reactive antibodies in the pathogenesis of spondyloarthropathies.
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PMID:Molecular mimicry in the pathogenesis of spondyloarthropathies. A critical appraisal of cross-reactivity between microbial antigens and HLA-B27. 155 37

Ankylosing spondylitis is a form of reactive arthritis following Klebsiella infection, usually occurring in an HLA-B27-positive individual. This conclusion is based on evidence obtained from several disciplines: immunogenetic studies show that there is molecular mimicry between HLA-B27 and Klebsiella; increased isolation of fecal Klebsiella has been reported in both Europe and North America; and finally, antibodies to Klebsiella have been demonstrated in ankylosing spondylitis patients in England and Finland. It is suggested that therapeutic trials should be set up with the aim of eliminating Klebsiella microbes, in an endeavor to test the validity of this theory.
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PMID:Ankylosing spondylitis is caused by Klebsiella. Evidence from immunogenetic, microbiologic, and serologic studies. 156 97

Some microorganisms which are pathogenic in humans share amino acid sequences with human proteins (molecular mimicry). It has been suggested that molecular mimicry might be a reason for autoimmunity as a result of immunological cross reactivity. A homologous sequence of six amino acids has been found in both Klebsiella pneumoniae nitrogenase and the HLA-B27.5 molecule. In addition, (auto)antibodies to a synthetic peptide that contained the HLA-B27.5/klebsiella mimicking epitope have been detected in serum samples from HLA-B27 positive patients with ankylosing spondylitis and Reiter's syndrome. Confirmation of these data is important, because ankylosing spondylitis and Reiter's syndrome have so far been assumed to be 'seronegative' rheumatic diseases. It was, however, not possible to confirm the presence of autoantibodies against the mimicking peptide in serum samples from patients with ankylosing spondylitis and Reiter's syndrome. Serum samples from 81 patients with ankylosing spondylitis, 38 patients with Reiter's syndrome, and 81 healthy blood donors were tested against the 'mimicking peptide' in an enzyme linked immunosorbent assay (ELISA). Some of the serum samples from patients showed high but non-specific binding to the mimicking peptide. A highly significant correlation between binding to plastic coated with the mimicking peptide, to plastic coated with an irrelevant peptide, and even to non-coated plastic was observed. The nature of the serum component(s) in these patient serum samples (and some control serum samples) responsible for the high non-specific binding to plastic remains unclear. It was also shown that antibodies to the HLA-B27 peptide (containing the mimicking epitope) induced in rabbits do not cross react with the klebsiella peptide and vice versa.
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PMID:Absence of autoantibodies to peptides shared by HLA-B27.5 and Klebsiella pneumoniae nitrogenase in serum samples from HLA-B27 positive patients with ankylosing spondylitis and Reiter's syndrome. 161 64

One hundred and fourteen patients with acute anterior uveitis were studied for the presence of the HLA-B27 tissue type, the prevalence of spondylitis and arthritis and the occurrence of gastro-intestinal and urogenital infections or diarrhoeal illness in the history. Eighty-seven (76%) were B27+ and 27 (24%) B27-. Forty-two (48%) of the B27+ group had ankylosing spondylitis (AS); 13 (30%) of them were females. Sacroilitis (SI) with no spinal involvement was present in 21 patients (24%), 13 (61%) males and 8 (38%) females. Peripheral arthritis occurred in 6 patients. Thus, 68 (78%) of the HLA-B27+ positive patients had inflammatory spinal and/or joint disease, compared with 1 (4%) of the HLA-B27- group (p less than 0.001). The AS diagnosis was unknown previous to our examination in 31% of the males and 54% of the females, and SI was undiscovered in 61% of the males and 62% of the females. The occurrence of acute enteric infections was significantly increased in the B27+ AAU group, compared with the B27- patients and the patients reported exacerbation of AAU in connection with episodes of diarrhoea. An increased occurrence of urogenital infections was shown only in co-comparison with the males of the B-27+ AAU group. Thirty-three out of 47 AAU patients assayed by enzyme immuno-assay (EIA) for the quantification of IgM, IgA and IgG antibodies against Klebsiella pneumoniae, E coli, and Proteus mirabilis had significantly raised antibody titres against one or more of the antibodies studied, as compared to 62 healthy controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Acute anterior uveitis, arthritides and enteric antigens. 180 94

A study was made of immunity in seronegative spondylarthritis. In ankylosing spondylarthritis, reactive arthritides and psoriatic arthritis, the decrease of T cells, T helpers and T suppressors was identified. Patients with ankylosing spondylarthritis and reactive arthritides manifested an increase of the B-lymphocyte count. Patients with ankylosing spondylarthritis were demonstrated to be sensitive to Klebsiella (52%), those with reactive arthritides to intestinal yersinia (44%). The phenotype of antigen-binding cells was examined. Of these, 39% appeared to be T lymphocytes, 29% B lymphocytes. The presence of Fc receptors in an appreciable portion of those cells suggests their functional maturity. The inhibition test demonstrated the participation of HLA-B27 in reception of Klebsiella antigens in ankylosing spondylarthritis.
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PMID:[Immune disorders and sensitization to microbial antigens in seronegative spondylitis]. 188 24

We previously reported elevated serum antibody levels to a peptide representing the HLA-B27 polymorphic region (B27 peptide) in HLA-B27(+) ankylosing spondylitis (AS) patients. A plasmid (pHS-2) isolated from arthritogenic Shigella flexneri strains had been shown to encode an amino acid sequence homologous to HLA-B27. Rabbit antibody to this sequence (pHS-2 peptide) strongly cross-reacted with B27 peptide and, to a much lesser extent, with Klebsiella nitrogenase peptide. Serum antibody levels to pHS-2 peptide were studied in 160 spondylarthropathy patients. 12 of 115 (10.4%) AS patients, 2 of 45 (4.4%) patients with Reiter's syndrome or reactive arthritis as well as 6 of 147 (4.1%) normal controls were shown to have elevated anti-pHS-2 peptide antibodies. Antibody levels to B27 and pHS-2 peptides were significantly correlated in 134 HLA-B27(+) patients (r = 0.333, P less than 0.001). 13 of 15 affinity-purified anti-B27 peptide antibodies from patients strongly cross-reacted with pHS-2 peptide, whereas only 3 weakly cross-reacted to nitrogenase peptide. Leucine appeared to be a critical residue for this cross-reaction. AS patients' anti-B27 peptide antibodies reacted with HLA-B27 transfected L cells. These results may suggest that pHS-2 peptide more efficiently "mimics" B27 peptide than does nitrogenase peptide. Involvement of pHS-2 in pathogenesis of spondylarthropathy through molecular mimicry mechanisms requires further study.
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PMID:Autoantibodies to the HLA-B27 sequence cross-react with the hypothetical peptide from the arthritis-associated Shigella plasmid. 221 8

Geczy found that rabbit sera raised against Klebsiella strain K43 cross-reacted with the cells from HLA-B27 positive patients with ankylosing spondylitis (AS). Other laboratories failed to reproduce these results. After a series of unsuccessful attempts, however, we managed to prepare one selective antiserum, using E. coli, isolated from a Dutch Bechterew patient, in offspring of rabbits Geczy sent us. Ever since we obtained irreproducible results only. This paper reports about the many attempts we have made to produce a discriminating antiserum for use in a combined vital stain and dye-exclusion assay.
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PMID:Trial and error in producing ankylosing-spondylitis-selective antisera according to Andrew Geczy. 225 90

1. Twenty-eight patients with active definite primary ankylosing spondylitis and fifty-four healthy control subjects were studied. 2. The HLA-B27 antigen was found in 75% of patients and 3.7% of controls. 3. Fecal samples from these subjects were cultured for gram-negative enteric bacteria on two occasions within one month. Positive cultures for Klebsiella sp were found in 32.1% of patients and in 22.2% of healthy controls, but this difference was not statistically significant. All other microorganisms detected were qualitatively and quantitatively similar in both groups. 4. Significantly increased mean values of serum IgA levels were found in the patient group when compared with the control group (P less than 0.01). The mean serum IgG and IgM levels did not differ statistically between the two groups. There was no correlation between any laboratory or clinical parameter and presence of Klebsiella sp carriage in ankylosing spondylitis patients. 5. These data are consistent with the view that a long time elapses between exposure to a trigger factor and clinical manifestations of the disease.
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PMID:A study of the gram-negative bacterial flora in patients with ankylosing spondylitis. 238 46


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