Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003864 (arthritis)
 69,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Antibodies to recombinant heterogeneous nuclear RNP core protein A1 were detected in sera from 27 of 58 patients with rheumatoid arthritis (RA) and from 7 of 31 patients with systemic lupus erythematosus, by immunoblotting and enzyme-linked immunosorbent assay. Protein A1 consists of 2 distinct domains: The N-terminal sequence is identical to a single-stranded DNA binding protein termed UP1, and the C-terminal domain shows a partial homology with keratin. All 7 A1-positive systemic lupus erythematosus sera reacted with UP1, whereas 9 of the 27 A1-positive RA sera did not. In RA, anti-A1 activity was significantly associated with antikeratin antibodies (AKA); these antibodies were present in 23 of 27 A1-positive sera and 10 of 31 A1-negative sera (P less than 0.01). Immunoabsorption with recombinant protein A1 resulted in a significant reduction of AKA titers in 6 of 10 RA sera tested, suggesting that AKA from RA patients may cross-react with the C-terminal portion of the heterogeneous nuclear RNP protein A1.
Arthritis Rheum 1990 Feb
PMID:Antibodies from patients with rheumatoid arthritis and systemic lupus erythematosus recognize different epitopes of a single heterogeneous nuclear RNP core protein. Possible role of cross-reacting antikeratin antibodies. 168 80

Serum antibodies reactive with the keratin layer of rat esophagus (AKA) were found in 46 of 80 (57.5%) rheumatoid arthritis (RA) patients. In contrast, AKA were present in only 7 of 82 (9.5%) patients with other types of rheumatic disorders and in 2 of 47 (4.2%) healthy subjects. AKA were not specific for RA, however, because in the former group, AKA were present in 4 of 20 (20%) systemic sclerosis patients and in 3 of 12 (25%) ankylosing spondylitis patients. AKA belong predominantly to the IgG class and are complement fixing. Although found in some RA joint fluids, AKA were not selectively concentrated in the joint fluid. Absorption of RA serum with type I human collagen or with human epidermal keratin did not remove AKA activity. The frequency of AKA in RA patients both negative and positive for DR4 was equal. There was no relationship between the frequency of AKA and the occurrence of other serum autoantibodies such as antibodies to intermediate filaments, smooth muscle, and nuclear antigens. Serum antibody reactive with human stratum corneum found in patients with psoriatic arthritis was shown to be different from AKA. Rabbit antiserum to human keratin did not inhibit the reaction of AKA against the keratin layer of rat esophagus. Autoimmunity to structural proteins including collagen, vimentin intermediate filaments, smooth muscle antigens, and keratin is a characteristic feature of RA.
Arthritis Rheum 1983 Apr
PMID:Reactivity of serum antibodies to the keratin layer of rat esophagus in patients with rheumatoid arthritis. 618 70

Experimental intervertebral disc degeneration produced in rabbits by ventral nuclear herniation reliably produces vertebral osteophytes. Osteophytes arise from proliferating inner annular fibers which undergo metaplasia into cartilage, calcify, and proceed through an endochondral ossification sequence. Proteoglycans extracted from the osteophytes reveal that the degree of aggregation, molecular size of the monomer, and the chondroitin sulfate/keratin sulfate ratio are directly related to the cartilage state of the tissue.
Arthritis Rheum 1980 Mar
PMID:Vertebral osteophyte formation in experimental disc degeneration. Morphologic and proteoglycan changes over time. 736 83

Human parvovirus B19 infection in adults shows some clinical features similar to those found in autoimmune connective tissue diseases. To better clarify the relationship between viral infection and autoimmunity, we have evaluated the ability of anti-parvovirus antibodies to specifically recognize autoantigens in ten patients with chronic symmetric arthritis resembling rheumatoid arthritis or with recurrent episodes of arthritis and cutaneous manifestations and persistence of specific IgM antibodies against B19 parvovirus. We synthetized a 24-amino acid immunodominant peptide corresponding to a part of the virus protein 1 and virus protein 2 overlapping region. The peptide has been used to test patients' sera at different time points with an enzyme-linked immunosorbent assay (ELISA) and to purify anti-virus antibodies by affinity chromatography on a peptide-Sepharose column. Eluted immunoglobulins recognized the B19 peptide in both direct and competitive ELISA. Affinity-purified anti-parvovirus antibodies were then tested on a panel of autoantigens including human keratin, collagen type II, thyreoglobulin, single-strand (ss)DNA, cardiolipin and ribonucleoprotein antigen Sm. Eluted antibodies specifically recognized keratin, collagen type II, ssDNA and cardiolipin. Autoantibody activity was not detected in the immunoglobulin fraction after complete removal of anti-peptide antibodies and in antibodies eluted from normal donors. Epstein-Barr virus-transformed cell clones obtained from two subjects produced antibodies which simultaneously recognize the viral peptide and several autoantigens. To further confirm the role of the virus in inducing an autoantibody response, eight BALB/c mice were immunized with the viral peptide coupled to a carrier protein. Autoantibody activity against keratin, collagen II, cardiolipin and ssDNA was detected in six of the eight mice which developed a strong anti-virus response. Together, these data indicate that B19 parvovirus may be linked to the induction of an autoimmune response.
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PMID:Chronic parvovirus B19 infection induces the production of anti-virus antibodies with autoantigen binding properties. 954 89

The caprine arthritis-encephalitis virus (CAEV) and Visna Maedi virus cause persistent infections with long latent periods and induce degenerative and chronic inflammatory lesions of the central nervous system, joints, lungs and udder. Monocyte/macrophage lineage is the main target cell for CAEV and Visna Maedi virus but we speculate that mammary epithelial cells may also be infected. Primary cultures of milk cells, mammary tissues of experimentally and naturally infected goats and ewes were used. Primary cultures of mammary tissue from ewes and goats were infected with the CAEV Cork strain. The lentiviral infection of the primary culture was demonstrated by a typical cytopathic effect in mammary epithelial cells and the presence of an infectious virus in coculture with permissive fibroblasts. To identify the epithelial cells in explants and demonstrate the antigenic expression of CAEV, primary cultures were immunostained with polyclonal anti-keratin and monoclonal anti-CAEV p30. Colocalisation studies under a UV fluorescence microscope and by epifluorescence microscopy showed the expression of specific viral antigens in mammary epithelial cells from the eight animals used. Infected mammary epithelial cells may act as a reservoir for the virus which may play an important role in the virus dissemination and in the pathogenesis of the mammary lentiviral disease.
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PMID:Infection of primary cultures of mammary epithelial cells by small ruminant lentiviruses. 1054 81

STATEMENT OF FINDINGS: An inception cohort of 238 patients having peripheral joint synovitis of less than 12 months duration was evaluated clinically and followed prospectively for 1 year to determine the clinical significance of a number of rheumatoid arthritis (RA) associated autoantibodies. Serum samples collected at the time of the initial evaluation were tested for rheumatoid factor (RF) and antibodies to Sa (anti-Sa), RA-33, (pro)filaggrin [antifilaggrin antibody (AFA)], cyclic citrullinated peptide (anti-CCP), calpastatin, and keratin [antikeratin antibody (AKA)]. RF had a sensitivity of 66% and a specificity of 87% for RA. Anti-Sa, AFA, and anti-CCP all had a specificity of more than 90%, but a sensitivity of less than 50% for this diagnosis. Overall, there was a high degree of correlation between AFA, AKA, anti-Sa or anti-CCP, this being highest between anti-Sa and anti-CCP (odds ratio, 13.3; P < 0.001). Of the 101 patients who were positive for at least one of these four autoantibodies, 57% were positive for only one. Finally, anti-SA identified a subset of predominantly male RA patients with severe, erosive disease. Anti-SA, AFA and anti-CCP are all specific for early RA but, overall, have little additional diagnostic value over RF alone. Although these antibodies may preferentially recognize citrullinated antigens, the modest degree of concordance between them in individual patient sera suggests that it is unlikely a single antigen is involved in generating these responses.
Arthritis Res 2000
PMID:Rheumatoid arthritis associated autoantibodies in patients with synovitis of recent onset. 1105 69

Methylsulfonylmethane (MSM) is a popular dietary supplement used in a variety of conditions including pain, inflammation, allergies, arthritis, parasitic infections and the maintenance of normal keratin levels in hair, skin and nails. Despite its popularity, there is little published toxicology data on MSM. The objective of this study was to evaluate the acute and subchronic toxicity of MSM in rats at a dose five to seven times the maximum recommended dose in humans. MSM administered in a single gavage dose of 2 g/kg resulted in no adverse events or mortality. MSM administered as a daily dose of 1.5 g/kg for 90 days by gavage resulted in no adverse events or mortality. Necropsy did not reveal any gross pathological lesions or changes in organ weights. Renal histology of treated animals was normal. It is concluded that MSM is well tolerated in rats at an acute dose of 2 g/kg and at a subacute chronic dose of 1.5 g/kg.
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PMID:Toxicity of methylsulfonylmethane in rats. 1238 9

We analysed the presence of anti-cyclic citrullinated peptide (anti-CCP) and anti-keratin (AKA) antibodies of the IgG class in sera of patients with defined juvenile idiopathic arthritis (JIA) of various subgroups with more than one year duration of the disease. Enzyme-linked immunosorbent assay (Immunoscan RA, Eurodiagnostica, The Netherlands) and an indirect immunofluorescence (IIF) test on rat oesophagus substrate (ImmuGloTM, Immco Diagnostics, Buffalo, USA) were used for the detection and quantification of anti-CCP and AKA antibodies in 140 patients with JIA (64 male and 76 female) aged 2-47 years (median 16.5 years). Overall, anti-CCP were found in 7/140 (5.0%) patients including 3/52 RF negative polyarthritis, 2/18 RF positive polyarthritis, 1/15 enthesitis related arthritis and 1/5 unclassifiable arthritis. AKA were detected in 40/140 patients (28.6%, p = 0.04) including 2/11 systemic arthritis, 2/32 oligoarthritis, 18/52 patients with RF negative polyarthritis (34.6%, p = 0.01), 14/18 RF positive polyarthritis (77.8%, p = 0.000002), 2/15 enthesitis related arthritis and 2/3 psoriatic arthritis. While simultaneous negativity for AKA and anti-CCP occurred in most (97/140; 69.3%) studied cases, simultaneous antibody positivity was found only in few (4/140; 2.9%) studied samples. We conclude that while AKA measured using IIF on rat esophagus can be detected approximately in one third of patients with definite JIA with more than 1 year duration of the disease, only rare occurrence of anti-CCP was observed. We conclude that AKA seem to be partly useful to confirm JIA diagnosis, however, useless to follow-up severity or activity in JIA patients. Anti-CCP do not have any additional value in MA cohort in comparison to RA where their diagnostic and prognostic importance was reported.
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PMID:Anti-cyclic citrullinated peptide antibodies in patients with juvenile idiopathic arthritis. 1256 20

The objective of the study was to determine the diagnostic value for rheumatoid arthritis (RA) of anti-filaggrin autoantibodies (autoAb) recognizing citrullinated recombinant rat filaggrin (ACRF) in community cases of very early arthritis. To evaluate the diagnostic value of ACRF, were studied sera from patients with different classified rheumatic diseases and healthy subjects (group 1, n= 422) and 314 community cases of very early arthritis (group 2) that were classified as RA (n = 176), non-RA (n = 63) and undifferentiated (n = 75) arthritides after 1 years of follow-up. ACRF were measured using a new ELISA, with results expressed as the difference between the OD value obtained on citrullinated minus that on noncitrullinated rat filaggrin (differential ACRF; dACRF). For both groups, rheumatoid factors (RF), anti-keratin autoAb (AKA) and anti-perinuclear factor (APF) were tested; for group 2, anti-CCP autoAb were also tested. Different reactivity patterns against citrullinated and noncitrullinated filaggrin were observed. Almost all sera reacting with citrullinated but not noncitrullinated filaggrin were from RA patients. Among RA and non-RA sera that recognized both forms of filaggrin, a positive result was obtained only with RA sera. For groups 1 and 2, dACRF sensitivity was 58.4% and 30.7%, and specificity for RA was 99.5% and 98.4%, respectively. In group 2, dACRF specificity for RA was better than that of RF (92.1%), APF (95.2%), AKA (96.8%) and anti-CCP (95.2%). dACRF positive predictive value was high (98.2) and close to that given by the concomitant positivity of RF and anti-CCP autoAb. Despite a high positive correlation between AKA, APF, anti-CCP and dACRF test results, they were complementary since some sera were positive for only one test. Thus, in a community setting, anti-citrullinated rat filaggrin reactivity detected by a new ELISA, whose originality is based on the difference between serum's reactivities on the citrullinated and native forms of filaggrin, had a higher diagnostic value for RA than other autoAb.
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PMID:Autoantibodies recognizing citrullinated rat filaggrin in an ELISA using citrullinated and non-citrullinated recombinant proteins as antigens are highly diagnostic for rheumatoid arthritis. 1467 80

Interleukin-1 receptor antagonist-deficient (Il1rn-/-) BALB/c mice developed inflammation localized to the skin of the ear pinna in 64% of the cases examined. Histopathologically, the disease had many features resembling human psoriasis, suggesting that it might be a useful disease model. The epidermis became thickened and hypertrophic, and expressed the immature keratin, K6, throughout. The stratum corneum showed parakeratotsis. Large epidermal projections formed into a grossly thickened dermis and both tissues were infiltrated by leukocytes. Neutrophil-rich microabscesses formed beneath the stratum corneum. Dendritic cells and activated T cells of both helper classes were identified in both the dermis and epidermis, while a high density of macrophages was seen in the dermis, where mast cells were also prominent. Dense patterns of apparently activated small dermal vessels were seen in the diseased dermis. Cutaneous inflammation, along with arterial inflammation and arthritis, is the third site-specific, inflammatory disease to be found to affect Il1rn-/- BALB/c mice. None of the diseases affected Il1rn-/- C57BL/6. In F2 hybrids of Il1rn-/- BALB/c and C57BL/6, cutaneous inflammation was absent, aortic inflammation was common, and arthritis was rare, indicating that the sets of background modifier genes that cause susceptibility to each disease are not fully overlapping.
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PMID:Psoriasis-like cutaneous inflammation in mice lacking interleukin-1 receptor antagonist. 1508 51


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