IgA antibody response to klebsiella in ankylosing spondylitis measured by immunoblotting

Inverse correlation between CD4+ CD25high CD127low/- regulatory T-cells and serum immunoglobulin A in patients with new-onset ankylosing spondylitis

This study investigated the role of regulatory T (T(reg)) cells in patients with new-onset, treatment-naïve ankylosing spondylitis (AS). Levels of CD4(+)CD25(high)CD127(low/-) T(reg) cells in the peripheral blood of 14 AS patients and 18 age-matched healthy volunteers were investigated by flow cytometry and correlations with serum levels of immunoglobulin A (IgA) and AS activity, as assessed by the Bath AS Disease Activity Index (BASDAI), were analysed. The number of peripheral blood CD4(+)CD25(high)CD127(low/-) T(reg) cells in AS patients was found to be significantly lower than in healthy controls and was inversely correlated with serum IgA levels. There was no significant correlation between CD4(+)CD25(high)CD127(low/-) T(reg) cell numbers and BASDAI scores. It is concluded that CD4(+)CD25(high)CD127(low/-) T(reg) cells may play a role in the pathogenesis and activity of AS.

First report of septic arthritis caused by Klebsiella oxytoca

Klebsiella oxytoca is known to be a pathogen in immunodeficient adults and children. Here we report the first case of a K. oxytoca infection associated with spontaneous arthritis of the knee in a child with no history of immunosuppressive therapy or previous bacterial infections. Despite an initial antibiotic treatment failure, a second treatment led to a cure of the infection with no joint sequelae.

Ankylosing spondylitis is linked to Klebsiella--the evidence

Ankylosing spondylitis (AS) is a chronic inflammatory spinal and large-joint arthritic and potentially disabling condition, mainly affecting males of young age groups. Extensive literature based on the results of various genetic, microbiological, molecular and immunological studies carried out by independent research groups suggests that Klebsiella pneumoniae is the main microbial agent being implicated as a triggering and/or perpetuating factor in the etiopathogenesis of AS. Novel diagnostic markers and criteria based on the association with high anti-Klebsiella antibodies could be used in the detection of AS patients during early stages of the disease, and together with the current treatments might help in implementing the use of new therapeutic anti-microbial measures in the management of AS. Prospective longitudinal studies with the use of anti-microbial measures in patients with AS are required to establish the therapeutic benefit of this microbe-disease association.

Infectious background of patients with a history of acute anterior uveitis

OBJECTIVE

To study the infectious background of patients with a history of acute anterior uveitis (AAU) and healthy control subjects.

METHODS

Sixty four patients with previous AAU and 64 sex and age matched controls were studied. Serum antibodies to Salmonellae, Yersiniae, Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, Campylobacter jejuni, and Borrelia burgdorferi were measured using enzyme linked immunosorbent assay (ELISA), and antibodies to Chlamydia trachomatis and Chlamydia pneumoniae by microimmunofluorescence test. Peripheral blood mononuclear cells (PBMCs), separated by density gradient centrifugation, were studied for Salmonella and Yersinia antigens by means of an immunofluorescence test, and for C pneumoniae DNA with a polymerase chain reaction (PCR).

RESULTS

Neither prevalence nor levels of single microbial antibodies studied differed between the patients and control subjects, or between subgroups of patients created on the basis of clinical characteristics. In logistic regression analysis, the high number of recurrences (>10) of AAU was independently related to the presence of single or multiple bacterial antibodies (p=0.04). None of the PBMC samples of the patients were positive for Yersinia or Salmonella antigens. C pneumoniae PCR was positive in a patient who was negative for C pneumoniae antibodies.

CONCLUSION

Although neither the prevalence nor the levels of single microbial antibodies studied differed between the patients and the controls, current data suggest that the presence of single or multiple antibodies in patients with many recurrences of AAU compared with patients with none or few recurrences may be a sign of repeated infections, antigen persistence, or raised innate immune responsiveness.

Streptokinase promotes development of dipeptidyl peptidase IV (CD26) autoantibodies after fibrinolytic therapy in myocardial infarction patients

Dipeptidyl peptidase IV (DPP IV) (CD26) plays a critical role in the modulation and expression of autoimmune and inflammatory diseases. We recently reported that sera from patients with rheumatoid arthritis and systemic lupus erythematosus contained low levels of DPP IV and high titers of anti-DPP IV autoantibodies of the immunoglobulin A (IgA) and IgG classes and found a correlation between the low circulating levels of DPP IV and the high titers of anti-DPP IV autoantibodies of the IgA class. Since streptokinase (SK) is a potent immunogen and binds to DPP IV, we speculated that patients with autoimmune diseases showed higher DPP IV autoantibody levels than healthy controls as a consequence of an abnormal immune stimulation triggered by SK released during streptococcal infections. We assessed this hypothesis in a group of patients suffering from acute myocardial infarction, without a chronic autoimmune disease, who received SK as part of therapeutic thrombolysis. Concomitant with the appearance of anti-SK antibodies, these patients developed anti-DPP IV autoantibodies. These autoantibodies bind to DPP IV in the region which is also recognized by SK, suggesting that an SK-induced immune response is responsible for the appearance of DPP IV autoantibodies. Furthermore, we determined a correlation between high titers of DPP IV autoantibodies and an augmented clearance of the enzyme from the circulation. Serum levels of the inflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) increased significantly after 30 days of SK administration, while the levels of soluble IL-2 receptor remained unchanged during the same period, suggesting a correlation between the lower levels of circulating DPP IV and higher levels of TNF-alpha and IL-6 in serum in these patients.

Correlation between the immune responses to collagens type I, III, IV and V and Klebsiella pneumoniae in patients with Crohn's disease and ankylosing spondylitis

BACKGROUND

Increased levels of collagen types I, III and V are found in strictures of patients with Crohn's disease (CD) compared with normal gut tissue. Type IV collagen is present in the basement membranes, basal lamina, retina and cornea. Elevated levels of antibody to Klebsiella pneumoniae are found in both active CD and active ankylosing spondylitis (AS) patients compared with healthy controls.

METHODS

Reactivities for immunoglobulin class-specific antibodies (IgM, IgG and IgA) against collagen types I, III, IV, V and whole K. pneumoniae were measured by ELISA in nine patients with early CD and 10 with late CD from King's College Hospital and 12 late CD patients and 36 HLA-B27-positive AS patients from Middlesex Hospital and was compared with values for 26 healthy controls from the Blood Transfusion Service in London.

RESULTS

Levels of class-specific IgM, IgG and IgA antibodies to collagen types I, III, IV, V and K. pneumoniae were significantly elevated in early and late CD patients compared with healthy controls (P<0.001). Levels of IgM, IgG antibody to the four collagen types and K. pneumoniae were also significantly elevated (P<0.001) in AS patients compared with healthy controls. In addition, the level of IgA antibody to K. pneumoniae was elevated in AS patients (P<0.001). Furthermore, a positive correlation between antibody levels to collagen types I, III, IV and K. pneumoniae was demonstrated in both early and late CD patients and in those with AS, whilst a positive correlation to type V was found in early CD.

CONCLUSION

The role of K. pneumoniae and anti-collagen antibodies in the aetiopathogenesis of CD and AS requires further study.

Molecular mimicry between HLA-DR alleles associated with rheumatoid arthritis and Proteus mirabilis as the Aetiological basis for autoimmunity

Molecular mimicry is one of the pathological mechanisms proposed to explain the association between microorganisms and autoimmune diseases. This review deals with the association between bacteria and rheumatic diseases with a special emphasis on rheumatoid arthritis where upper urinary tract infection by Proteus mirabilis is the possible cause of this severe, arthritic condition. Prospective trials involving anti-Proteus therapy should be carried out.

Juvenile-onset spondyloarthropathies

This article discusses the clinical spectrum and characteristics of juvenile-onset spondyloarthropathies and includes a review of the demographic, clinical, radiographic (and other imaging techniques), and laboratory data of conditions, syndromes, and diseases making up this group. The pathogenic role of several factors in the context of adult-onset patients, but also in regards to studies already performed in juvenile-onset patients, is discussed.

Ig A antibodies to klebsiella in ankylosing spondylitis

In this study anti-klebsiella Ig A values were compared in 40 patients with definite diagnosis of ankylosing spondylitis and a control group of 40 healthy subjects. Anti-Klebsiella Ig A antibody values were significantly higher in patients with ankylosing spondylitis as compared to the control group (p < 0.001). Correlation between these antibodies and erythrocyte sedimentation rate, CRP, serum Ig A, HLA B 27, age, sex and disease duration was searched, but no correlation was found. In our opinion, these results support the suggestion that inflammatory response in ankylosing spondylitis is triggered by Klebsiella but is insufficient to prove the causal relationship between ankylosing spondylitis and Klebsiella.

Serum secretory immunoglobulins in ankylosing spondylitis

Humoral mucosal immunity may be implicated in pathophysiology of ankylosing spondylitis (AS). The aim of the study was to evaluate serum levels of IgA, IgM and secretory IgA (sIgA), secretory IgM (sIgM) as well as free secretory component (FSC) in patients with AS compared to controls and rheumatoid arthritis (RA) patients. Levels of sIgA, sIgM and FSC were measured with a specific ELISA in 37 AS patients, 45 controls and 27 RA. The results were as follows: Serum levels of IgA were higher in AS vs controls and in RA vs controls (p = 0.01). Levels of sIgA were higher in AS vs controls (p = 0.01), but higher in RA vs AS (p = 10(-4)). There was no difference of sIgM in AS vs controls, FSC levels were higher in AS vs controls, and higher in AS patients with elevated CRP. In view of elevated FSC, this increase of sIgA in AS may have been due to excessive production of mucosal IgA after bacterial stimulation according to the current hypothesis of the disease.

IgA antibodies against Klebsiella and other Gram-negative bacteria in ankylosing spondylitis and acute anterior uveitis

Mucosal infections, especially of the gastrointestinal tract, are thought to trigger the onset and/or reactivation of ankylosing spondylitis (AS). Previous investigations into the role of Klebsiella and other Gram-negative bacteria in AS patients show contrasting results. In the present study prevalence of IgA antibodies against Klebsiella, Yersinia, Salmonella, Shigella, and Campylobacter was examined in serum samples from 30 patients having HLA-B27 associated ankylosing spondylitis, 32 patients with HLA-B27 associated acute anterior uveitis (AAU), and 27 HLA-B27 positive patients having both AS and AAU. Numbers of antibodies were compared with those in sera from 29 HLA-B27 negative patients with AAU, 26 healthy HLA-B27 positive and 31 HLA-B27 negative controls. IgA antibodies were detected using an indirect immunofluorescence assay on whole bacteria. In case of Yersinia, Salmonella, Shigella and Campylobacter, reference strains were used. Examination for anti-Klebsiella antibodies was performed using three different strains, isolated from patients with ankylosing spondylitis. The sera were tested on antibodies against Klebsiella K43 (BTS1) as well. The number of IgA positive sera against Yersinia, Salmonella, Shigella, Campylobacter and Klebsiella K43 (BTS1) did not differ between HLA-B27 positive patients and controls, nor among the various groups. Differences were neither observed when the Klebsiella strains from AS patients had been used as antigen. These results do not confirm a relationship between HLA-B27 associated AS or AAU and infection with Klebsiella or other Gram-negative bacteria.

IgA antibodies in HLA-B27 associated acute anterior uveitis and ankylosing spondylitis

Acute anterior uveitis (AAU) and ankylosing spondylitis (AS) are, like reactive arthritis (ReA), strongly associated with HLA-B27. Mucosal infections play a role in the pathogenesis of ReA. To investigate whether these microorganisms are also involved in the pathogenesis of AAU and AS, we examined blood samples from patients with AAU, AS or both, and healthy controls for presence of antibodies against Klebsiella pneumoniae (K 30), Salmonella enteritidis and S. typhimurium, Chlamydia trachomatis, Proteus mirabilis and Borrelia burgdorferi. The IgA, IgG and IgM classes of these antibodies were measured using an enzyme-linked immunosorbent assay. No significant differences were found in the frequency in which these antibodies occurred in HLA-B27 positive patients with AAU or AS and healthy controls. However, IgA antibodies against K. pneumoniae (p < 0.01) and IgA and IgG antibodies against P. mirabilis (p < 0.01 and p < 0.05) were detected more frequently in HLA-B27 negative patients with AAU than in healthy controls. The results of this study are in contrast with various earlier reports in which antibodies against Klebsiella strains were more frequently found in patients with HLA-B27 associated ankylosing spondylitis than in healthy controls.

IgA1 and IgA2 subclass antibodies against Klebsiella pneumoniae in the sera of patients with peripheral and axial types of ankylosing spondylitis

OBJECTIVE

To study further the Klebsiella specific serum antibody response in patients with axial and peripheral types of ankylosing spondylitis (AS).

METHODS

IgA1 and IgA2 subclass antibodies to Klebsiella pneumoniae were measured by enzyme linked immunosorbent assay in the sera of 171 patients with axial or peripheral type AS, and in sera of 100 healthy controls. The effect of 26 weeks of sulphasalazine treatment on the antibody levels in the two types of AS was also analysed.

RESULTS

K pneumoniae specific antibody levels of both IgA1 and IgA2 subclasses were increased in the sera of patients with AS compared with healthy controls. The increased levels were present in patients with axial and with peripheral AS, and there were no statistically significant differences in the antibody levels between these two groups. Sulphasalazine treatment decreased the Klebsiella specific antibody level of IgA1 subclass in patients with axial AS, but there were no statistically significant changes in the IgA2 subclass, or in the patients with peripheral type AS.

CONCLUSIONS

These results agree with earlier published findings suggesting that IgA (especially Klebsiella specific IgA) may have a role in the pathogenetic mechanisms of both peripheral and axial types of AS. In addition, it seems that both IgA1 and IgA2 subclasses are involved in the disease process.

Spondylarthropathy and selective IgA deficiency

No serum IgA was detected in a young male patient suffering from spondylarthropathy (SpA) with bilateral sacroiliitis arthritis, enthesopathy and inflammatory low back pain, whose symptoms occurred in reaction to a sexually induced urethritis. After a period of several months in which the spondylarthropathy was active, disease activity came to a rest. Three years later no progression of the SpA was observed. This finding might be an indication that IgA is not involved in the pathogenesis of spondylarthropathy.

Comparison of the antibody responses to the 77 Klebsiella capsular types in ankylosing spondylitis and various rheumatic diseases

The production of antibodies to Klebsiella capsular polysaccharides was measured in sera from either HLA-B27-positive (HLA-B27+) or HLA-B27-negative (HLA-B27-) patients with classical ankylosing spondylitis (n = 54). These sera were compared with sera from patients with various rheumatic diseases (n = 82) and HLA-B27+ or HLA-B27- healthy individuals (n = 85). All sera were analyzed by means of an enzyme-linked immunosorbent assay specific to each of the 77 Klebsiella serotypes. The sera from HLA-B27+ patients with ankylosing spondylitis showed a significantly higher antibody frequency to the capsular types K26, K36, and K50 than the sera from HLA-B27- ankylosing spondylitis patients, patients with psoriatic arthritis, systemic lupus erythematosus, rheumatoid arthritis, or reactive arthritis after Yersinia enterocolitica infection, or healthy controls (P < 0.02). The antibodies were of the immunoglobulin G type. No significant antibody response to the other 74 Klebsiella serotypes, noncapsulated mutants of K26, K36, and K50, or preparations of Citrobacter, Serratia, Hafnia, or Morganella spp. or Streptococcus pneumoniae could be detected. The results might suggest a specific association between these capsular types and HLA-B27+ ankylosing spondylitis and might imply their predominance in this disease.

Serum antibodies to Klebsiella capsular polysaccharides in ankylosing spondylitis

OBJECTIVE

To measure antibodies to Klebsiella capsular polysaccharides in the sera of HLA-B27 positive patients with ankylosing spondylitis (AS), compared with HLA-B27 positive and HLA-B27 negative healthy control subjects.

METHODS

Antibodies were detected by means of an enzyme-linked immunosorbent assay specific for each of the 77 known Klebsiella serotypes.

RESULTS

Significantly elevated frequencies and titers of antibodies to capsular polysaccharides K26, K36, and K50 were detected in sera from AS patients, compared with controls.

CONCLUSION

These results suggest the predominance of Klebsiella serotypes K26, K36, and K50 in patients with AS.

[Spondylarthropathies and the IgA system]

The spondyloarthropathies (SA) implicate bacterial infections of mucosal origin. IgA synthesis capacity in vitro is normal in AS. IgA increase is secondary to a specific immune response to the bacterial antigens implicated in the disease's pathogenesis. IgA participate to immune complex formation, which may lead to some extraarticular features of the disease (e.g. renal, cutaneous or vascular). There is also an increase of secretory IgA reflecting the activation of the two compartments of this humoral immune response, part of a coherent pathophysiological scheme of the disease. In a practical point of view, IgA serum levels may be considered as a biological parameter of SA activity.