Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01889 (ankylosing spondylitis)
 5,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prognosis in the majority of patients with acute reactive arthritis is usually good, with most patients recovering in a few months. In about 15% to 30% of such patients, the disease progresses, and spondyloarthropathy and even ankylosing spondylitis develop in the following 10 to 20 years. A recurrent attack of reactive arthritis is common in patients with chlamydia-triggered arthritis, but it is rare in patients who have had enteroarthritis. In patients with chronic spondyloarthropathy without evidence of preceding infection, the disease can progress slowly into ankylosing spondylitis. When reactive chlamydia arthritis is indicated, a prolonged course of antibiotics is needed. For other forms of reactive arthritis, solid evidence in favor of antibiotic therapy is still lacking. Presence of hip pain, decreased mobility of thoracic cervical or thoracic spine, heel pain, inflammatory gut lesions, high erythrocyte sedimentation rate, positive family history, and presence of human leukocyte antigen B27 are indicators for chronicity. Sulfasalazine might be of use in chronic arthritis and ankylosing spondylitis, especially if the patient has peripheral arthritis.
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PMID:Prognosis, course of disease, and treatment of the spondyloarthropathies. 989 8

Eye inflammation, especially uveitis, is a prominent feature of spondyloarthropathies. Uveitis associated with ankylosing spondylitis and Reiter's syndrome usually is a unilateral acute anterior uveitis with a high tendency to recur sometimes in the contralateral eye. Uveitis associated with undifferentiated spondyloarthropathy, inflammatory bowel disease, and psoriasis may be less characteristic in its presentation, with a higher tendency to posterior pole involvement, bilaterality, and chronicity. Although acute anterior uveitis is grouped into the spectrum of human leukocyte antigen B27-related disease, other genetic and environmental factors including infections by gram-negative bacteria and gut inflammation can play a role in its pathogenesis. The prognosis of uveitis usually is excellent with topical treatment, and only those with posterior pole involvement or a high tendency to recur or to chronicity might benefit from immunosuppressive therapy.
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PMID:Eye involvement in the spondyloarthropathies. 989 10

In the spondyloarthropathies human leukocyte antigen (HLA) B27 confers a strong genetic predisposition to the development and to the chronicity of disease after extra-articular infection with certain gram-negative bacteria. The close relationships between infection, HLA-B27, other genetic factors, and the host immune system, however, still are unexplained. HLA-B27-positive arthritis continues to be an area of intensive investigation in basic and clinical research. New animal models with HLA-B27 transgenic mice and rats, as well as recent developments in understanding the processes involved in signal transduction, cytokine production, and human T-lymphocyte activation, contribute to the development of new pathogenic models of the spondyloarthropathies. This article summarizes the current concepts of the cause and pathogenesis of the spondyloarthropathies resulting from studies of clinical materials. The host-microbial interplay in human disease, namely in bacteria-induced reactive arthritis, may eludicate principle disease mechanisms in acute disease and in the development of chronic autoimmune arthritis or ankylosing spondylitis.
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PMID:Pathogenesis of human leukocyte antigen B27-positive arthritis. Information from clinical materials. 989 15

One of the strongest known association between human leukocyte antigen (HLA) phenotype and disease is that of ankylosing spondylitis and HLA-B27. Thus, the determination of HLA-B27 status is an useful tool in the diagnosis of ankylosing spondylitis. To date, the 2 reference methods for HLA typing (microlymphocytotoxicity and molecular biology techniques), are costly in terms of both technician time and materials, and require a great deal of experience. In total, these techniques are not well-suited for routine application in clinical immunology laboratories. Use of flow cytometry has recently been applied for HLA-B27 typing. Nevertheless, it requires an extensive validation protocol. We developed a flow cytometry technique as standardized as possible (whole blood, automated lysing system, automated photomultiplier voltage calibration, definition of thresholds stable with time) and validated our results by comparison with microlymphocytotoxicity. In total, 326 samples were analyzed. We found 99% of concordant results between the 2 techniques, and neither false positive results nor false negative results with flow cytometry could be observed. These results illustrate the reliability of the protocol. It should be remembered that reference technique remains necessary to confirm the few results (< 1%) found in "grey zone" by flow cytometry. Standardization of flow cytometry techniques, as described in this work for HLA B27, seems to be a reasonable goal for the next decade in clinical immunology laboratories.
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PMID:[Standardization and automation of HLA B27 typing by flow cytometry: validation and comparison with microlymphocytotoxicity]. 1093 47

A growing body of evidence suggests that T lymphocytes play an important role in initiating and maintaining the inflammatory process characteristic of the human leukocyte antigen (HLA)-B27-associated spondyloarthropathies. T cells seem to be involved in the primary defense reaction against arthritis-triggering gram-negative bacteria at the site of extra-articular infection, in determining the systemic cytokine pattern, in the recirculation process between gut mucosa and the joint, and in mediating secondary autoimmune joint inflammation. The factors involved in disease chronicity (namely in ankylosing spondylitis and psoriatic arthritis) are still unknown. Autoreactive T cells may contribute to this process by recognition of cross-reactive self-epitopes (ie, molecular mimicry between bacterial and self-antigens). Autoreactive T cells may as well be inappropriately upregulated by bacterial superantigens, or by local inflammatory reactions leading to the uncovering of former cryptic self-epitopes. In this paper, we review recent studies on peripheral blood and synovial T cells in patients with reactive arthritis, enteropathic spondyloarthropathy, psoriatic arthritis, and ankylosing spondylitis.
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PMID:T-cell studies in the spondyloarthropathies. 1112 74

The pathology of ankylosing spondylitis (AS) and related spondyloarthropathies (SpA) characteristically involve a sacroiliitis and inflammation of the intervertebral discs (IVD) in the lumbar spine, and an enthesitis at sites of ligamentous insertions into bone. The proteoglycans aggrecan and versican are large molecules that aggregate with hyaluronic via a globular 1 domain. These domains share significant homology at the level of B and T cell epitope recognition. Both proteoglycans are present in the intervertebral disc and hyaline cartilages of the sacroiliac joint, as well as in entheses. Whereas aggrecan is most concentrated in the nucleus of the IVD and in articular cartilages and endplates, versican is generally absent from these tissues except in the sacroiliac joint, but is concentrated in ligaments and the annulus. Immunity to these molecules in BALB/c mice results in an AS-like pathology, including sacroiliitis, enthesitis, and discitis. The pathology of AS is closely associated with the expression of the class I molecule human leukocyte antigen-B27. Rats bearing this transgene develop an AS-like pathology, as well as other various signs of autoimmunity. Ankylosing spondylitis is characterized by an ankylosing pathology whereby bone formation in the annulus leads to intervertebral fusion. Mice bearing the ank/ank defect gene develop a bony ankylosis of the spine like that seen in advanced AS and related SpA. These three animal models provide insight into the pathogenesis of SpA, and opportunities to investigate their pathology in relationship to human disease where investigation of the pathobiology is very difficult, because of restricted access to involved tissues.
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PMID:Animal models of ankylosing spondylitis. 1242 66

To perform an investigation regarding the distribution of the human leukocyte antigen (HLA)-B27 subtypes in the Zulian population with ankylosing spondylitis (AS), 48 unrelated Mestizos, HLA-B27 positive by serology, were studied using the polymerase chain reaction-specific sequence oligonucleotides probe (PCR-SSOP) and specific sequence primers (SSP) to analyze the polymorphism in exons 2 and 3 of the HLA-B27 gene. Only two of eight HLA-B27 subtypes studied (B*2701-B*2708) were found. The distribution of these alleles in the population of patients was: B*2705, 68.8%, and B*2702, 31.2%. B*2705 subtype showed significant association with patients being male. In the healthy controls, the most common subtype was B*2708. These results were compared with frequencies reported in other Mestizo and Spanish populations and showed significant differences, such as a high frequency of B*2702. Such results show that HLA*B2705 and HLA*B2702 are the subtypes most frequently associated with AS in our Mestizo population and suggest a possible protector role for HLA*B2708, which was found only in the healthy population.
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PMID:HLA-B27 subtypes determination in patients with ankylosing spondylitis from Zulia, Venezuela. 1282 78

The products of the human leukocyte antigen subtypes HLA-B*2705 and HLA-B*2709 differ only in residue 116 (Asp vs. His) within the peptide binding groove but are differentially associated with the autoimmune disease ankylosing spondylitis (AS); HLA-B*2705 occurs in AS-patients, whereas HLA-B*2709 does not. The subtypes also generate differential T cell repertoires as exemplified by distinct T cell responses against the self-peptide pVIPR (RRKWRRWHL). The crystal structures described here show that pVIPR binds in an unprecedented dual conformation only to HLA-B*2705 molecules. In one binding mode, peptide pArg5 forms a salt bridge to Asp116, connected with drastically different interactions between peptide and heavy chain, contrasting with the second, conventional conformation, which is exclusively found in the case of B*2709. These subtype-dependent differences in pVIPR binding link the emergence of dissimilar T cell repertoires in individuals with HLA-B*2705 or HLA-B*2709 to the buried Asp116/His116 polymorphism and provide novel insights into peptide presentation by major histocompatibility antigens.
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PMID:Dual, HLA-B27 subtype-dependent conformation of a self-peptide. 1473 27

For more than 30 years, human leukocyte antigen B27 (HLA-B27) has been known to be closely related to the autoimmune disease ankylosing spondylitis, yet little is known about the molecular mechanisms of pathogenesis. Crystal structures of two closely related, but differently disease-associated, subtypes (B*2705 and B*2709) also did not resolve this situation as they revealed the bound nonapeptide in essentially identical conformations. As the peptide is part of putative binding epitopes for the T cell receptor, we performed molecular dynamics simulations to gain deeper insight into the dynamic behaviour of HLA-B27 molecules. We find increased flexibility of the peptide in the binding groove of subtype B*2709 due to weaker interactions in the F pocket. Possible implications of this flexibility for T cell recognition and signalling are discussed.
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PMID:A single residue exchange between two HLA-B27 alleles triggers increased peptide flexibility. 1501 9

In 2003, several manuscripts on the classification of patients as having ankylosing spondylitis and the further development of outcome assessment tools have been published. It is obvious that the use of radiographic sacroiliitis is a problematic part of the classification criteria because there is major interobserver variation and is one of the causes of a long delay between onset of symptoms and diagnosis. Especially in patients without human leukocyte antigen B27, the diagnostic delay is long. Existing outcome tools, such as the Bath Ankylosing Spondylitis Disease Activity Index, have been adapted and validated for use in other languages. New instruments to assess quality of life (Ankylosing Spondylitis Quality of Life Index; Patient Generated Index) and physical functioning (World Health Organization Disability Assessment Schedule II) have been developed and validated for the use in ankylosing spondylitis. In addition, a new and feasible tool to assess enthesitis has been constructed and validated. Because fatigue is an important symptom for patients with ankylosing spondylitis, a recommendation to use a specific fatigue instrument was created. The statistically derived Assessment in Ankylosing Spondylitis response criteria have been compared with expert opinion and are strict criteria. Responders as defined by the Assessment in Ankylosing Spondylitis response criteria also are considered by the experts as responders.
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PMID:New directions in classification and outcome assessment in ankylosing spondylitis. 1501 39


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