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ID PMID Title PublicationDate abstract
12051394 Prevalence of HTLV-I Tax in a subset of patients with rheumatoid arthritis. 2002 Mar OBJECTIVE: In regions of the world where the human T cell lymphotropic virus type I (HTLV-I) is endemic, it is recognized that infection with this virus is associated with autoimmune diseases such as rheumatoid arthritis (RA). Moreover, mice transgenic for the HTLV-I Tax gene develop a disease akin to RA. The observation that about 8% of healthy American blood donors carry HTLV-I Tax in their lymphocytes (1) prompted studies to determine whether Tax positivity is more prevalent among patients with RA and if so, whether its sequence is homologous with prototypic HTLV-I Tax. This proved to be the case. Of 102 patients with RA tested, one was a carrier of HTLV-I and 25 had the Tax sequences in their mononuclear cells and antibodies to p40 Tax in their sera, while being negative for antibodies to the structural proteins of the virus. METHODS: Blood was collectedfrom 102 RA patients. Lysates of their mononuclear cells were assayed for HTLV-I Tax by PCR/Southern analysis, and in some positive cases Tax sequence analysis was performed. Antibodies to p40 Tax, the gene product of the Tax sequence, were detected by western blot assay using recombinant p40 Tax as antigen. Results Of the 102 patients tested, one proved to be a carrier of the virus, having antibodies and sequences for the viral structural proteins, gag and env in addition to p40 Tax. Twenty-five of the 101 HTLV-I/II seronegative patients carried both HTLV-I Tax sequences in their mononuclear cells and had antibodies to p40 Tax. Sequence analysis confirmed homology with HTLV-I Tax. CONCLUSION: The data show that the prevalence of HTLV-I Tax positivity among patients with RA is -3 times higher than among healthy blood donors. Since Tax is known to be involved in the development of numerous autoimmune diseases, the possibility that it is responsible for the development of RA in a subpopulation of patients with this disease is not remote.
12081195 Expression of the duffy antigen/receptor for chemokines (DARC) by the inflamed synovial en 2002 May The expression of chemokine binding sites on the endothelial cells of venules in inflamed synovia was examined and whether the Duffy antigen/receptor for chemokines (DARC) was involved. In situ binding assays were performed to determine the expression of chemokine binding sites from rheumatoid (n = 10) and non-rheumatoid (n = 10) synovia. The expression of DARC protein and mRNA was examined by immunohistochemistry and northern blotting. The involvement of DARC in chemokine binding was studied by incubating sections with blocking antibodies to DARC (Fy3 and 6), to find out if these reduced 125I-IL-8 binding. Binding of radiolabelled chemokines IL-8, RANTES, MCP-1, but not MIP-1alpha, was found on venular endothelial cells in inflamed synovia from both rheumatoid and non-rheumatoid patients. Excess homologous unlabelled chemokine displaced binding and excess unlabelled RANTES could displace radiolabelled IL-8 binding. DARC protein expression was demonstrated on venular endothelial cells in all samples and DARC mRNA could be detected in extracts from synovia. There was downregulation of DARC protein and mRNA in rheumatoid samples. Binding of IL-8 to both rheumatoid and non-rheumatoid synovia was significantly reduced in the presence of anti-DARC Fy3 and Fy6 monoclonal antibodies. These findings show the expression of a multispecific chemokine binding site on the inflamed synovial endothelium, with evidence for involvement of DARC. This suggests a potential role for DARC in the inflammatory processes involved in synovitis.
12371632 Is there an association of plasma homocysteine levels with vascular involvement in patient 2002 Jul OBJECTIVE: To assess whether or not plasma homocysteine levels play a part in vascular involvement in Behçet's syndrome (BS). METHODS: 74 consecutive BS patients fulfilling the criteria of the International Study Group for BS, 35 healthy control (HC) and 14 rheumatoid arthritis (RA) patients on methotrexate (MTX) were studied. BS patients were then classified as those with and without vascular involvement. Fasting plasma homocysteine, folate, and vitamin B12 concentrations were measured by enzyme immunoassay and chemiluminescent immunoassay methods respectively. RESULTS: Plasma homocysteine levels were found to be higher in the BS patients than in the healthy control (16.08 +/- 7.5 vs. 12.9 +/- 6.3 micromol/L, p < 0.03). The homocysteine levels in the RA group on MTX were higher compared with both the BS and HC groups (28.7 +/- 9.9; p < 0.0001). No remarkable difference pertaining to homocysteine levels was found between BS patients with or without thrombosis (p < 0.86). Hyperhomocysteinemia was also detected in 11 out of 22 (50%) of the patients with vascular involvement, which proved to be of no significant difference in comparison with those without vascular involvement (20/52, 38%; chi2 = 0.26, p > 0.05). Active BS smokers exhibited a higher concentration of homocysteine in contrast to non-smoker BS sufferers (20 +/- 8.4 vs 14.1 +/- 6.1 micromol/l; p < 0.004). Smoking was determined to have a positive correlation with vascular involvement (r = 0.26, p < 0.046), as well as with homocysteine levels (r = 0.31, p < 0.012) in BS. Upon logistic regression analysis, smoking was found to have a significant relationship with vascular involvement (odds ratio 3.12 [95% CI 2.02-4.22] p = 0.04). There was no significant difference between the study groups with respect to their B12 vitamin and folate levels. We were unable to make any correlation between homocysteine and vitamin B12 or folate in any of the groups (p > 0.05). CONCLUSIONS: No association was found between homocysteine levels and vascular involvement in our BS patients. We determined that smoking seems to pose a risk for vascular involvement in BS patients.
15082480 Efficacy and safety of adalimumab as monotherapy in patients with rheumatoid arthritis for 2004 May OBJECTIVE: To evaluate the efficacy and safety of monotherapy with adalimumab in patients with RA for whom previous DMARD treatment has failed. METHODS: In a 26 week, double blind, placebo controlled, phase III trial, 544 patients with RA were randomised to monotherapy with adalimumab 20 mg every other week, 20 mg weekly, 40 mg every other week, 40 mg weekly, or placebo. The primary efficacy end point was > or =20% improvement in the ACR core criteria (ACR20 response). Secondary efficacy end points included ACR50, ACR70, EULAR responses, and the Disability Index of the Health Assessment Questionnaire (HAQ DI). RESULTS: After 26 weeks, patients treated with adalimumab 20 mg every other week, 20 mg weekly, 40 mg every other week, and 40 mg weekly had significantly better response rates than those treated with placebo: ACR20 (35.8%, 39.3%, 46.0%, 53.4%, respectively v 19.1%; p< or =0.01); ACR50 (18.9%, 20.5%, 22.1%, 35.0% v 8.2%; p< or =0.05); ACR70 (8.5%, 9.8%, 12.4%, 18.4% v 1.8%; p< or =0.05). Moderate EULAR response rates were significantly greater with adalimumab than with placebo (41.5%, 48.2%, 55.8%, 63.1% v 26.4%; p< or =0.05). Patients treated with adalimumab achieved better improvements in mean HAQ DI than those receiving placebo (-0.29, -0.39, -0.38, -0.49 v -0.07; p< or =0.01). No significant differences were found between adalimumab and placebo treated patients for serious adverse events, serious infections, or malignancies. Injection site reaction occurred in 10.6% and 0.9% of adalimumab and placebo treated patients, respectively (p< or =0.05). CONCLUSION: Among patients with RA for whom previous DMARD treatment had failed, adalimumab monotherapy achieved significant, rapid, and sustained improvements in disease activity and improved physical function and was safe and well tolerated.
14677194 The compliance-questionnaire-rheumatology compared with electronic medication event monito 2003 Nov OBJECTIVE: To validate the 19-item Compliance-Questionnaire-Rheumatology (CQR) against the "gold standard" in compliance measurement, electronic medication event monitoring. METHODS: Among 127 consenting patients, 81 with rheumatoid arthritis taking nonsteroidal antiinflammatory drugs (13 diclofenac, 20 naproxen) or disease modifying antirheumatic drugs (25 sulfasalazine, 23 methotrexate), 17 patients with polymyalgia rheumatica taking prednisone, and 29 patients with gout taking daily prophylactic colchicine (n = 12) or the uric acid lowering drugs allopurinol (10) or benzbromaron (7), 104 used their medication from a regular medication bottle fitted with a special cap containing microelectronics capable of recording time and date of opening and closing, defined as a medication event. Data were processed for the following: (1) the percentage of prescribed medication events during the study period (taking compliance) and (2) the percentage of days with the prescribed number of medication events (i.e., correct dosing). Satisfactory compliance was defined as taking compliance or correct dosing > 80%, while unsatisfactory compliance was defined as taking compliance or correct dosing < or = 80%. All patients were informed about the monitoring, and were followed for 6 months (gout: 1 year). At baseline 85 patients completed a set of questionnaires including the 19-item CQR. RESULTS: A total of 85 patients who had complete questionnaire and electronic monitoring data were analyzed. Multiple linear regression analyses showed that the total, weighted CQR score significantly and adequately predicts taking compliance (p = 0.001, r2 = 0.46) and correct dosing (p = 0.004, r2 = 0.42). Discriminant analyses showed that specificity and sensitivity to detect good taking compliance were 95% and 62%, respectively, with a prevalence of good compliance of 52%. The predictive value to detect unsatisfactory taking compliance was 86%, and to detect good taking compliance was 83%. The likelihood ratio of the CQR-19 to detect low taking compliance was 11.6. Four items were especially predictive: fear of forgetting to take the drug, being able to function well, routines in daily life, and side effects (combined r2 = 0.35). CONCLUSION: These results support the validity of the Compliance Questionnaire Rheumatology.
12177236 Study of the mechanism involved in angiogenesis and synovial cell proliferation in human s 2002 Aug To examine whether synovial cell proliferation is due to angiogenesis, we studied the relationship between the inhibition of synovial cell proliferation and an angiogenesis inhibitor, TNP-470, in human synovial tissues. Human synovial tissues were implanted into the back of SCID mice (SCID-HuAg mice). Sixteen mice were divided into two groups of eight mice each: the untreated group (vehicle group) and the TNP-470-treated group that received a dose of 10 mg/kg body weight by subcutaneous injection. The number of blood vessels and synovial lining cells clearly increased in the vehicle group, but the number of synovial lining cells clearly decreased and the blood vessels were hardly detected in the TNP-470 group. Immunohistochemically, cells that stained positively for the anti-proliferating cell nuclear antigen (PCNA) mAb were abundant in synovial lining cells and endothelial cells in synovial tissues. Cells that stained positively for the anti-CD34 polyclonal antibody were abundant in the endothelial cells in the vehicle group, but these positively stained cells were hardly detected in the TNP-470 group. The PCNA positivity ratio in the vehicle group was 0.64 +/- 0.019, whereas that in the TNP-470 group was 0.199 +/- 0.007. The numbers of cells that stained positively for anti-CD34 polyclonal antibody were 242 +/- 13.4 in the vehicle group and 153 +/- 6.73 in the TNP-470 group per 10 microscopic fields. Cells that stained positively for anti-mouse CD31 mAb were mainly localized in the synovial lining, but invaded the subsynovial lining layer in human synovial tissues. On the other hand, cells that stained positively for anti-human CD31 mAb were mainly localized in the subsynovial lining layer. We found that endothelial cell proliferation is dependent on angiogenesis based on the result that angiogenesis and synovial cell proliferation were inhibited by treatment with TNP-470.
12937872 Heavy users of non-steroidal anti-inflammatory drugs: a nationwide prescription database s 2003 Sep OBJECTIVE: To describe characteristics of non-steroidal anti-inflammatory drugs (NSAIDs; Anatomical Therapeutic Chemical code M01A) users in Finland, with emphasis on intensity of use. METHODS: Nationwide prescription database study over years 1997-2000 using a random sample of 500,000 persons. Low use was defined as 30 or fewer defined daily doses (DDDs) per year, moderate between 31 and 181 DDDs, and heavy 182 or more DDDs. Persons with rheumatoid arthritis (RA) were identified and analysed separately from non-RA patients. RESULTS: The total NSAID consumption was 61.2 and reimbursed prescription NSAID use 31.2 DDD/1000 inhabitants per day in 2000. The annual prevalence of use varied between 17.1% and 18.8% throughout 1997-2000, and that of low, moderate and heavy use was 7.6%, 8.0% and 1.5%, respectively, in 2000. Females used more NSAIDs than men in all adult non-RA age groups, and of non-RA patients 58.4% were females. The share of females among the non-RA users increased with the intensity of use, as did the share of female patients 65 years or older. Among RA patients, the intensity of use was independent of age and gender, and 70% of RA patients were females. Of the heavy users in 2000, 27.7% ( n=2117) had continuously used 182 or more DDDs per year throughout the years 1997-2000. Non-RA users accounted for 78.4% of the annual heavy and 64.2% of the continuous heavy users. CONCLUSIONS: Exposure of patients to long-term use of NSAIDs and upper gastrointestinal bleeding should be reduced by regular analysis of patient's pain and consideration of other treatment options.
15334484 Reduced infiltration and increased apoptosis of leukocytes at sites of inflammation by sys 2004 Aug OBJECTIVE: NF-kappaB activation is associated with several inflammatory disorders, including rheumatoid arthritis (RA), making this family of transcription factors a good target for the development of antiinflammatory treatments. Although inhibitors of the NF-kappaB pathway are currently available, their specificity has not been adequately determined. IkappaBalpha is a physiologic inhibitor of NF-kappaB and a potent repressor experimentally when expressed in a nondegradable form. We describe here a novel means for specifically regulating NF-kappaB activity in vivo by administering a chimeric molecule comprising the super-repressor IkappaBalpha (srIkappaBalpha) fused to the membrane-transducing domain of the human immunodeficiency virus Tat protein (Tat-srIkappaBalpha). METHODS: The Wistar rat carrageenan-induced pleurisy model was used to assess the effects of in vivo administration of Tat-srIkappaBalpha on leukocyte infiltration and on cytokine and chemokine production. RESULTS: Systemic administration of Tat-srIkappaBalpha diminished infiltration of leukocytes into the site of inflammation. Analysis of the recruited inflammatory cells confirmed uptake of the inhibitor and reduction of the NF-kappaB activity. These cells exhibited elevated caspase activity, suggesting that NF-kappaB is required for the survival of leukocytes at sites of inflammation. Analysis of exudates, while showing decreases in the production of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-1beta, also revealed a significant increase in the production of the neutrophil chemoattractants cytokine-induced neutrophil chemoattractant 1 (CINC-1) and CINC-3 compared with controls. This result could reveal a previously unknown feedback mechanism in which infiltrating leukocytes may down-regulate local production of these chemokines. CONCLUSION: These results provide new insights into the etiology of inflammation and establish a strategy for developing novel therapeutics by regulating the signaling activity of pathways known to function in RA.
15603272 [Is there a future for COX-2 inhibitors?]. 2004 Nov The two cyclooxygenase isoforms (COX-1 and COX-2--coxibs) have overlapping functions and both are involved in the regulation of homeostatic and inflammatory processes in the various tissues. Treatment with highly selective COX-2 inhibitors is associated with significantly fewer serious adverse gastrointestinal events than is treatment with the dual inhibitors--the non-selective NSAIDs. Of the two coxibs, rofecoxib was shown to be much more selective than celecoxib and with less interaction with other drugs. Various clinical studies have demonstrated that the coxibs are equivalent, in anti-inflammatory, analgesic and antipyretic efficacy to comparator non-selective NSAIDs in osteoarthritis, rheumatoid arthritis, post surgery pain and dysmenorrhea. Perioperative use of coxibs reduces pain, opioid consumption and the risk of bleeding caused by the non-selective NSAIDs. The coxibs show similar tolerability for renal, liver and cardiothrombotic events as compared to the non-selective NSAIDs. Coxibs are contraindicated in pregnancy, in nursing mothers and pediatric patients and should be used with caution in patients with asthma. The impact of the coxibs on the cardiovascular system is controversial. However, coxibs should be used in caution and at the lowest recommended dose in patients with hypertension, ischemic heart disease and heart failure. These drugs do not interfere with the aspirin anti-platelet aggregation activity. Emerging evidence suggest that the coxibs may also find potential use as supportive therapy in various malignant tumors and intestinal polyps where COX-2 is overly expressed.
14585912 Channelling of patients taking NSAIDs or cyclooxygenase-2-specific inhibitors and its effe 2003 Nov When new drugs with improved safety or efficacy are introduced, they may be preferentially prescribed to specific populations of patients. Safety and efficacy may be underestimated if such channelling effects are not recognized. Meloxicam and cyclooxygenase (COX)-2-specific inhibitors were developed as safer alternatives to non-steroidal anti-inflammatory drugs (NSAIDs) for the treatment of osteoarthritis and rheumatoid arthritis. Studies of the use of meloxicam and COX-2-specific inhibitors demonstrate that both of these drugs are being prescribed to patients at increased risk of gastrointestinal adverse drug events. In the case of COX-2-specific inhibitors, this channelling appears to represent a prescribing pattern consistent with current recommendations. Subsequent analysis of the data, after adjusting for channelling bias, showed that the risk of gastrointestinal toxicity for meloxicam was similar to that for other NSAIDs, while COX-2-specific inhibitors reduced the risk of developing gastrointestinal adverse drug events by approximately 60%. These studies serve as examples of observed channelling bias and highlight the need for adjusting for channelling in order to provide a valid assessment of relevant outcomes for drugs likely to be preferentially prescribed to specific populations.
15161329 Valdecoxib: a review of its use in the management of osteoarthritis, rheumatoid arthritis, 2004 Valdecoxib is an orally administered, highly selective cyclo-oxygenase (COX)-2 inhibitor with anti-inflammatory and analgesic properties. In well designed trials, valdecoxib demonstrated efficacy versus placebo in patients with osteoarthritis (OA), rheumatoid arthritis (RA), primary dysmenorrhoea and postoperative pain. Initial results in patients with migraine headache were promising. The efficacy of valdecoxib appears dose dependent up to 40 mg/day. Valdecoxib 10 mg/day was as effective as naproxen and rofecoxib in improving signs and symptoms of OA. The American College of Rheumatology 20% response rate was similar in recipients of valdecoxib, naproxen and diclofenac in patients with RA. In patients with dysmenorrhoea, valdecoxib 20 or 40 mg up to twice daily provided as effective pain relief as naproxen sodium 550 mg twice daily. In acute post-surgical pain, single-dose valdecoxib 40 mg had a rapid onset of action, provided similar analgesia to oxycodone 10 mg plus paracetamol (acetaminophen) 1000 mg and provided a longer time to rescue medication than rofecoxib or oxycodone/paracetamol after oral surgery. Pre-emptive administration of valdecoxib 10-80 mg was particularly effective in dental pain. Valdecoxib had opioid-sparing effects after hip or knee arthroplasty and reduced pain after laparoscopic cholecystectomy. Valdecoxib is generally well tolerated. The incidence of gastroduodenal ulcers was generally lower than with nonselective NSAIDs (i.e. NSAIDs not specifically developed as selective COX-2 inhibitors). With concomitant aspirin, the ulcer rate in valdecoxib recipients increased significantly, but was still lower than that in recipients of aspirin plus nonselective NSAIDs. In conclusion, valdecoxib, a COX-2-selective inhibitor, is as efficacious in pain relief as nonselective NSAIDs, with better gastrointestinal tolerability. It was as effective in RA, OA and primary dysmenorrhoea (the approved indications) as nonselective NSAIDs and as effective as rofecoxib in RA flare. In acute post-surgical pain, valdecoxib provided similar pain relief to oxycodone/paracetamol, had a long duration of action, a rapid onset of analgesia and was opioid-sparing. Valdecoxib provides a valuable alternative in the treatment of chronic arthritis pain and acute pain.
12660227 NF-kappaB-dependent lymphocyte hyperadhesiveness to synovial fibroblasts by hypoxia and re 2003 Apr Hypoxia/reoxygenation has been incriminated as a major factor in the pathogenesis of ischemia/reperfusion injury in various ischemic diseases such as rheumatoid arthritis (RA). In this study, we have investigated the effect of hypoxia/reoxygenation on the expression of intercellular adhesion molecule-1 (ICAM-1) in synovial fibroblasts and adherence of lymphocytes to synovial fibroblasts. Hypoxia/reoxygenation strongly activated nuclear factor-kappaB (NF-kappaB) in synovial fibroblasts to the levels produced by phorbol 12-myristate 13-acetate and caused lymphocyte hyperadhesiveness to synovial fibroblasts as well as up-regulation of ICAM-1, both of which were completely blocked by a NF-kappaB antagonist (pyrrolidine dithiocarbamate). These results indicate that hypoxia/reoxygenation has a major role in sequestration of inflammatory cells to synovium mediated by the activation of NF-kappaB. Our data suggest that hypoxia/reoxygenation could be an important target for the development of new, therapeutic strategies in RA.
15320901 Immune complex-stimulated production of interleukin-12 in peripheral blood mononuclear cel 2004 Sep Immune complexes (IC) can induce cytokine production in vitro. While immune aggregates (IA) consisting of heat-aggregated gamma globulin (HAGG) as model IC increased interleukin (IL)-10 levels in cell cultures with native human serum, IL-12p40/p70 production was inhibited. Three series of experiments suggested that the effects of IA on IL-12 production depended on a functionally intact complement system: (1) heat-inactivation of serum inverted the inhibitory effect of IA on IL-12p40/p70 production; (2) IA-induced IL-12p40 production in a C4 deficient serum was lowered by addition of C4; and (3) addition of the peptide compstatin, which blocks C3 activation, mimicked the effects of heat inactivation on IL-12p40 levels. Neutralization of IL-12 resulted in modestly increased IL-10 levels, while neutralization of IL-10 had no effects on IL-12p40 production. IA-induced production of IL-10 was partially blocked by anti-Fcgamma RII antibodies, whereas Fcgamma R or CR blockade had no effect on IL-12p40 production. IC and local or systemic complement activation characterize rheumatoid arthritis, systemic lupus erythematosus and many malignancies. Different and complement-dependent effects on the production of IL-10 and IL-12 can be of importance in these diseases, where control of the complement system might be a way to direct IC-induced cytokine production in either a type 1 or type 2 direction.
12458822 Cost-effective use of NSAIDs: issues pertinent to coxib use in managed care. 2002 Nov The gastrointestinal toxicity of nonsteroidal anti-inflammatory drugs (NSAIDs) is well established. The management of patients requiring NSAID therapy has been revolutionized by the cyclooxygenase (COX)-2 inhibitors (coxibs), equally efficacious agents that significantly reduce GI complications. The safety advantage of coxibs comes at the expense of higher drug acquisition costs. To make informed decisions regarding the "value" of these added expenditures, a careful analysis of the clinical and economic impact of these new agents is warranted. This article focuses on the issues pertinent to healthcare payers as they evaluate the coxibs, and provides a review of the studies that calculate the cost-effectiveness of these innovative drugs in a number of patient populations and health systems.
11904958 [Overview of recent monoclonal antibody therapy]. 2002 Mar It has been 27 years since Milstein and Köhler stunned the world of biology by announcing the discovery of monoclonal antibodies. Novel MoAb improved forms of chimeric and humanized antibodies with high antigen-binding affinities are currently being developed by both genetic and chemical methods. The rapid growth of molecular techniques will permit the development of novel antibodies, which should significantly improve conventional therapeutic strategies. This report overviews recent advances in the field of monoclonal antibodies and provides insight regarding the promises and limitations of this novel therapeutic approach.
12415587 HLA and cytokine gene polymorphisms in relation to occurrence of palindromic rheumatism an 2002 Nov OBJECTIVE: Palindromic rheumatism (PR) is an episodic arthropathy that may precede typical rheumatoid arthritis (RA), although pathogenetic relationships between these disorders remain unclear. The predictive value for those immunogenetic risk factors implicated in RA for disease progression in PR remains to be established. A previous retrospective analysis from our group has implicated rheumatoid factor in disease progression. Our objective was to determine the contribution of HLA and cytokine gene polymorphisms implicated in RA to predisposition to PR and to progression of PR to chronic joint inflammation. METHODS: We studied 147 patients with PR seen in a tertiary referral center; 87 were selected retrospectively from the period 1986-96 using a structured selection process and 60 were selected prospectively in the period 1997-2001. Comparison groups included 149 patients with RA and 149 ethnically matched controls. Typing for HLA-DRB1 alleles and HLA-DRB1-04 subtypes was performed following polymerase chain reaction (PCR) amplification using sequence-specific primers (SSP). Cytokine genotypes were ascertained following PCR-SSP with and without digestion with restriction enzymes. Time-adjusted survival analysis (Kaplan-Meier) and multivariate logistic regression were used to assess the independent contribution of immunogenetic markers in assessing progression of PR to chronic joint inflammation. RESULTS: Thirty-one percent of patients progressed to connective tissue disease after a mean of 10.6 (retrospective group) and 3.9 (prospective group) years. A significantly increased prevalence of the shared epitope (SE) allele was noted in patients with PR (65%) versus controls (39%) (OR 2.9, 95% CI 1.8-4.6, p < 0.001). This primarily reflected increased prevalence of the DRB1-0401 and 0404 and not DRB1-01 alleles. A weak contribution to disease susceptibility was also noted with carriage of the IL4 promoter -590T (OR 1.8, 95% CI 1.1-3.0, p = 0.02) and IL4 intron 3 RP1 (OR 1.7, 95% CI 1.1-2.9, p = 0.03) alleles. The TNFa +489A allele was associated with RA (OR = 2.7, 95% CI 1.5-5.1, p = 0.001) in both SE+ and SE- patients, but not with PR. Time-adjusted and multivariate Cox regression analysis revealed that only homozygosity for SE alleles was a significant independent risk factor for disease progression to chronicity in PR (hazard ratio 2.9, 95% CI 1.2-6.9, p = 0.02). However, none of 8 patients homozygous for SE- DRB1 XP4n alleles developed chronic disease after 10 years of followup (p = 0.07). CONCLUSION: The immunogenetic risk profile for PR resembles that for RA, indicating that PR is likely not an independent entity. A significant gene dose effect for SE alleles is operative in determining risk for progression from PR to RA.
15290745 Autoantibodies in juvenile idiopathic arthritis: glucose-6-phosphate isomerase is not a sp 2004 Aug OBJECTIVE: Antibodies recognizing the ubiquitous cytosolic enzyme glucose-6-phosphate isomerase (GPI) cause arthritis in the K/BxN mouse model. Studies have shown that these antibodies are not specific for rheumatoid arthritis (RA) in humans. We evaluated GPI as a target of autoantibodies in juvenile idiopathic arthritis (JIA). METHODS: We studied 324 serum and 48 synovial fluid (SF) samples from 103 patients with JIA, 36 with RA, and 8 with arthralgia and 11 controls. Anti-GPI antibodies were assessed by densitometrically evaluating immunoblots and ELISA using native and recombinant GPI. We determined the GPI activity of the soluble antigen in serum and SF. RESULTS: Although several samples contained anti-GPI-IgG antibodies, this was not specific for JIA or its subgroups, or for RA. Other proteins in the GPI preparation were also frequently recognized by antibodies. Additionally, we observed increased GPI activity in patients with the systemic manifestation of JIA, but not in other patients. Neither anti-GPI concentrations nor GPI activity were associated with disease activity. CONCLUSION: In addition to the findings in RA, our results indicate that GPI is not a general target of autoantibodies in JIA.
14600836 Human osteoclasts express different CXC chemokines depending on cell culture substrate: mo 2003 Nov Chemokines are important mediators of chemotaxis, cell adherence, and proliferation and exert specific functions in bone remodeling. Despite the potential intriguing role of chemokines in the regulation of osteoclast (OC) functions, little is known about the expression of chemokines and their receptors in human OCs at different stages of differentiation. Therefore, we analyzed the expression of CXC chemokine receptors (CXCR1, CXCR2, CXCR3, CXCR4 and CXCR5) and ligands (CXCL8, CXCL10, CXCL12 and CXCL13) both at molecular and protein levels, in human OCs grown on plastic or calcium phosphate-coated slides at different stages of differentiation. Real-time PCR showed that CXCR1, CXCR2, CXCR3, CXCR4, CXCR5 and CXCL8 were expressed in undifferentiated cells and significantly decreased during OC differentiation. By contrast, CXCL10 and CXCL12 were strongly upregulated from day 0 to day 8 in cells grown on calcium phosphate-coated slides. Immunocytochemistry showed that OCs grown on plastic expressed CXCR3, CXCR4, CXCR5, CXCL8 and CXCL12, while they were negative for CXCR1, CXCR2 and CXCL10. Interestingly, both at molecular and protein levels CXCL10 and CXCL12 significantly increased only when cells were differentiated on calcium phosphate-coated slides. These data suggest that the selection of a substrate that better mimics the tridimensional structure of bone tissue, thus favoring OC maturation and differentiation, may be necessary when studying osteoclastogenesis in vitro.
15331725 Rheumatoid factors induce signaling from B cells, leading to Epstein-Barr virus and B-cell 2004 Sep B-cell antigen receptor signaling is initiated upon binding of the antigen to membrane-bound immunoblobulin (Ig), and the anti-Ig antibody (Ab) mimics this signaling. In B cells latently infected with Epstein-Barr virus (EBV), the same signals induce virus activation. We examine here whether rheumatoid factors (RFs), autoantibodies directed against the Fc portion of IgG, induce EBV and B-cell activation. As a source of RFs, RF-producing lymphoblastoid cell line (LCL) clones were isolated from peripheral blood mononuclear cells (PBMC) and synovial cells from patients with rheumatoid arthritis (RA) by EBV transformation. Burkitt's lymphoma-derived Akata cells, which are highly responsive to EBV activation by anti-Ig Abs, were used for the assay of EBV activation. Akata cells expressed IgG3 as membrane-bound Ig. RFs from a synovium-derived LCL were directed to IgG3 and induced EBV activation in 16 to 18% of Akata cells, whereas RFs from another synovium-derived LCL were directed to IgG1 and did not induce EBV activation. Pretreatment of RFs with the purified Fc fragment of human IgG completely abolished EBV activation. Furthermore, B-cell activation was assessed by incorporation of [3H]thymidine. RFs from synovium-derived LCLs efficiently induced B-cell activation, and the addition of CD40 ligand had a synergistic effect. On the other hand, RFs from PBMC-derived LCLs were polyreactive, had a lower affinity to IgG, and did not induce EBV and B-cell activation. The present findings imply a possible role for RFs as EBV and B-cell activators.
12759454 T cells of atopic asthmatics preferentially infiltrate into human bronchial xenografts in 2003 Jun 1 T cells play an important role in the pathogenesis of bronchial asthma. However, it is not completely known how circulating lymphocytes infiltrate into the airways of asthmatic patients. Because SCID mice are unable to reject xenogenic transplants, many xenotransplant models using various human tissues have been developed. Therefore, to examine the interaction between bronchi and T lymphocytes of asthma, it may be possible to use the human bronchial xenograft and PBMC xenograft in SCID mice. We transplanted human bronchi into the subcutaneum of SCID mice and i.p. injected PBMCs that were obtained from patients with atopic asthma, atopic dermatitis and rheumatoid arthritis, and normal subjects (asthmatic, dermatitis, rheumatic, and normal huPBMC-SCID mice). There was no difference in the percentage of CD3-, CD4-, CD8-, CD25-, CD45RO-, CD103-, and cutaneous lymphocyte Ag-positive cells in PBMCs among the patients with asthma, dermatitis, rheumatoid arthritis, and normal subjects, and CD3-positive cells in peripheral blood of asthmatic, dermatitis, rheumatic, and normal huPBMC-SCID mice. The number of CD3-, CD4-, and CD8-positive cells in the xenografts of asthmatic huPBMC-SCID mice was higher than those of dermatitis, rheumatic, and normal huPBMC-SCID mice. IL-4 mRNA and IL-5 mRNA were significantly higher in the xenografts of asthmatic huPBMC-SCID mice than those in the xenografts of normal huPBMC-SCID mice, but there were no significant differences in the expressions of IL-2 mRNA or IFN-gamma mRNA between them. These findings suggest that T cells, especially Th2-type T cells, of asthmatics preferentially infiltrate into the human bronchi.