Deletion of LCE3C and LCE3B is a susceptibility factor for psoriatic arthritis: a study in Spanish and Italian populations and meta-analysis.

OBJECTIVE: The LCE3C_LCE3B-del variant is associated with psoriasis and rheumatoid arthritis. Its role in psoriatic arthritis (PsA) is unclear, however, as shown by 3 recent studies with contradictory results. In order to investigate whether LCE3C_LCE3B-del constitutes a risk factor for PsA susceptibility, we first tested this variant in patients with PsA from Spanish and Italian populations and then performed a meta-analysis including the previous case-control studies. METHODS: We genotyped LCE3C_LCE3B-del and its tag single-nucleotide polymorphism (SNP), rs4112788, in an original discovery cohort of 424 Italian patients with PsA and 450 unaffected control subjects. A Spanish replication cohort consisting of 225 patients with PsA and 469 control subjects was also genotyped. A meta-analysis considering 7,758 control subjects and 2,325 patients with PsA was also performed. RESULTS: We observed a significant association between PsA and the LCE3C_LCE3B-del tag SNP in the Italian and Spanish cohorts, with an overall corrected P value of 0.00019 and a corresponding odds ratio of 1.35 (95% confidence interval 1.14-1.59). Stratified analyses by subphenotype indicated a stronger association for patients with oligoarticular disease. Meta-analysis including data from all previous published studies confirmed an association of PsA with the LCE3C_LCE3B-del tag SNP. CONCLUSION: LCE3C_LCE3B-del is a susceptibility factor for PsA, confirming the existence of a shared risk factor involving the epidermal skin barrier in autoimmune disorders.

High-dose etanercept in ankylosing spondylitis: results of a 12-week randomized, double blind, controlled multicentre study (LOADET study).

OBJECTIVES: Etanercept 50 mg a week is approved in the treatment of AS. Increasing the etanercept dose to 100 mg/week improves efficacy in cutaneous psoriasis, a clinical manifestation related to the spondylarthritis family, while maintaining its safety profile. The purpose of this study was to evaluate the efficacy and safety of etanercept 100 vs 50 mg/week in patients with AS. METHODS: Adult patients with AS were randomized to receive etanercept 50 mg twice a week (biw), or etanercept 50 mg once a week (qw) for 12 weeks. The primary efficacy endpoint was Ankylosing Spondylitis Assessment Study (ASAS20) response at Week 12; secondary endpoints included ASAS40, ASAS50, ASAS70 and ASAS5/6 responses, partial remission and quality of life. Safety was assessed until 15 days after the last visit. RESULTS: A total of 108 patients were randomly selected and treated, 54 in each arm. At 12 weeks, ASAS20 response was achieved by 34 (71%) out of 48 patients of the etanercept 50 mg biw group and by 37 (76%) out of 49 patients of the etanercept 50 mg qw group (not statistically significant differences). Other efficacy variables improved significantly over time, but not between treatment groups. Fifty-six patients experienced at least one adverse event (generally, infections and infestations, gastrointestinal disorders and injection site reactions), most of them mild or moderate. CONCLUSIONS: High-dose (100 mg/week) etanercept in the treatment of AS for 12 weeks is as safe as the standard dose (50 mg/week). However, it does not significantly increase its efficacy. Trial Registration. Clinicaltrials.gov, http://clinicaltrials.gov/, NCT00873730.

Synovial cytokine expression in psoriatic arthritis and associations with lymphoid neogenesis and clinical features.

INTRODUCTION: Psoriatic arthritis (PsA) is an autoantibody-negative immune-mediated disease in which synovial lymphoid neogenesis (LN) occurs. We determined whether LN is associated with specific patterns of inflammatory cytokine expression in paired synovial tissue (ST) and fluid (SF) samples and their potential correlation with the clinical characteristics of PsA. METHODS: ST and paired SF samples were obtained from the inflamed knee of PsA patients. ST samples were immunostained with CD3 (T cell), CD20 (B cell), and MECA-79 (high endothelial vessels). Total ST mRNA was extracted, and the gene expression of 21 T-cell-derived and proinflammatory cytokines were measured with quantitative real-time PCR. SF concentrations of Th1, Th2, Th17, and proinflammatory cytokines were determined with the Quantibody Human Th17 Array. Clinical and biologic data were collected at inclusion and after a median of 27 months of follow-up. RESULTS: Twenty (43.5%) of 46 patients had LN. Only two genes showed differences (Wilcoxon test, P < 0.06) in ST between LN-positive and LN-negative patients: interleukin-23A (IL-23A) (P = 0.058) and transforming growth factor-beta (TGF-ß1) (P = 0.050). IL-23A expression was higher, and TGF-ß1 expression was lower in LN-positive patients. ST IL-15 mRNA showed a nonsignificant trend toward higher expression in LN-positive patients, and SF IL-15 protein levels were significantly higher in LN-positive patients (P = 0.002). In all PsA patients, IL-23A mRNA expression correlated with C-reactive protein (CRP) (r = 0.471; P = 0.001) and swollen-joint count (SJC) (r = 0.350; P = 0.018), whereas SF levels of IL-6 and CC chemokine-ligand 20 (CCL-20) correlated with CRP levels (r = 0.377; P = 0.014 and r = 0.501; P < 0.0001, respectively). CONCLUSIONS: These findings suggest differences in the cytokine profile of PsA patients with LN, with a higher expression of IL-23A and IL-15 and a lower expression of TGF-ß1. In the entire group of patients, IL-23 ST expression and CCL20 SF levels strongly correlated with markers of disease activity. This cytokine pattern was not accompanied by gross clinical or biologic differences between LN-positive and -negative patients. Taken together, these results suggest a role of the IL-17/IL-23 cytokine axis in synovial LN in PsA.

Patient global assessment in psoriatic arthritis: a multicenter GRAPPA and OMERACT study.

OBJECTIVE: During OMERACT 8, delegates selected patient global assessment (PGA) of disease as a domain to be evaluated in randomized controlled trials in psoriatic arthritis (PsA). This study assessed the reliability of the PGA, measured by means of 0-100 mm visual analog scale (VAS), and the additional utility of separate VAS scales for joints (PJA) and skin (PSA). METHODS: In total, 319 consecutive patients with PsA (186 men, 133 women, mean age 51 ± 13 yrs) were enrolled. PGA, PJA, and PSA were administered at enrolment (W0) and after 1 week (W1). Detailed clinical data, including ACR joint count, Psoriasis Area and Severity Index (PASI), and Hospital Anxiety and Depression Scale, were recorded. RESULTS: Comparison of W0 and W1 scores showed no significant variations (intraclass correlation coefficients for PGA 0.87, PJA 0.86, PSA 0.78), demonstrating the reliability of the instrument. PGA scores were not influenced by patient anxiety or depression, but were dependent on PJA and PSA (p = 0.00001). PJA was dependent on the number of swollen and tender joints (p < 0.00001). PSA scores were influenced by the extent of skin psoriasis and by hand skin involvement (p = 0.00001). Joint and skin disease were found not to correlate in terms of disease activity as evidenced by the swollen joint count compared to PASI (r = 0.11) and by the PJA compared to PSA (r = 0.38). CONCLUSION: PGA assessed by means of VAS is a reliable tool related to joint and skin disease activity. Because joint and skin disease often diverge it is suggested that in some circumstances both PJA and PSA are also assessed.

Work disability in patients with ankylosing spondylitis.

OBJECTIVE: To determine the prevalence of work disability in Spanish patients with ankylosing spondylitis (AS) and to identify factors related to it. METHODS: A cross-sectional study based on data from Regisponser (National Spanish Registry of Patients with Spondyloarthropathy). Demographic and disease-related variables were collected. AS patients were classified as work-disabled according to the Spanish Social Security System criteria. Variables that discriminated between AS patients with and those without work disability were identified using chi-square test or unpaired t test when appropriate. Multiple logistic regression was performed. RESULTS: In total 699 AS patients, age 48.7 +/- SD 12.7 years and with disease duration 14.1 +/- 10.1 years, were analyzed; 179 patients (25.6%) had permanent work disability. Several variables had significantly different values in patients with compared to those without work disability. In the regression model (pseudo R(2) = 0.26, p < 0.0001), age (p = 0.001), sex (p = 0.04), disease duration (p = 0.006), total Bath AS Radiological Index (p = 0.007), Bath AS Functional Index (BASFI; p = 0.007), and chest expansion (p = 0.03) retained an independent association with work disability. When BASFI was excluded from the model the independent association with sex did not remain, and a significant association with finger to floor distance was found (p = 0.040). CONCLUSION: The prevalence of permanent work disability in Spanish patients with AS is significant, and the main factors related to it are age, disease duration, structural damage, and physical functioning. Longitudinal studies are needed to confirm these results.

Pig chondrocyte xenoimplants for human chondral defect repair: an in vitro model.

The objective of this study was to evaluate the use of cultured porcine chondrocyte xenotransplantation for the repair of human chondral defects. Two-millimeter-diameter defects were drilled into explants of femoral cartilage from healthy adult donors. No cells were implanted in the chondral defects of the control group, while pig chondrocytes from normal femoral cartilage were deposited into the treated chondral defects. Cartilage explants were cultured for 4, 8, and 12 weeks. Tissue sections were processed for standard histologic staining and immunostaining with monoclonal antibodies against types I and II collagen, chondroitin-4-sulfate, chondroitin-6-sulfate, keratan sulfate, and integrin subunit beta1. The porcine origin of chondrocytes was confirmed using a specific pig monoclonal anti-CD46. Repair was only observed in the cell-treated defects. Mono- or bilayers of cells were detected after 4 culture weeks on the bottom of the defects, while after 8-12 weeks a repair tissue filled near 30-40 percent of the defect. At 8 weeks, the newly synthesized tissue was composed of a fibrous mesh including some cells. However, at 12 weeks it showed a hypercellular hyaline-like region. This hypercellular region showed excellent bonding with the native cartilage, cells were located in numerous lacunae, and a high content of proteoglycans as indicated by an intense toluidine blue stain was observed. The repaired tissue showed positive immunostaining for both type I and II collagen, as well as chondroitin-4-sulfate, chondroitin-6-sulfate, keratan sulfate, and integrin subunit beta1. Positive staining for porcine anti-CD46 was localized exclusively in the neo-synthesized tissue. We conclude that xenotransplantation of pig chondrocytes can repair, in an in vitro model, defects in human articular cartilage.

Mitochondrial respiratory activity is altered in osteoarthritic human articular chondrocytes.

OBJECTIVE: Osteoarthritis (OA) is a degenerative rheumatic disease that is associated with extracellular matrix degradation and chondrocyte apoptosis in the articular cartilage. The role of mitochondria in degenerative diseases is widely recognized. We undertook this study to evaluate mitochondrial function in normal and OA chondrocytes and to examine age-related changes in mitochondria. METHODS: Mitochondrial function was evaluated by analyzing respiratory chain enzyme complexes and citrate synthase (CS) activities as well as changes in mitochondrial membrane potential (Delta Psi m). The activities of mitochondrial respiratory chain complexes (complex I: rotenone-sensitive NADH-coenzyme Q(1) reductase; complex II: succinate dehydrogenase; complex III: antimycin-sensitive ubiquinol cytochrome c reductase; and complex IV: cytochrome c oxidase) and CS were measured in human articular chondrocytes isolated from OA and normal cartilage. Delta Psi m was measured by JC-1 using flow cytometry. Statistical analysis was performed using the Mann-Whitney U test and Student's t-test as well as several models of multiple linear regression. RESULTS: OA articular chondrocytes had reduced activities of complexes II and III compared with cells from normal cartilage. However, the mitochondrial mass was increased in OA. Cultures of OA chondrocytes contained a higher proportion of cells with de-energized mitochondria. We found no relationship between mitochondrial function and donor age either in normal or in OA chondrocytes. CONCLUSION: These findings suggest the involvement of mitochondrial function in the pathophysiology of OA. Cartilage degradation by OA and cartilage aging may be two different processes.

Xeno-implantation of pig chondrocytes into rabbit to treat localized articular cartilage defects: an animal model.

Articular cartilage has only a limited ability to regenerate. The transplantation of autologous chondrocytes is currently used to treat focal defects in human articular cartilage, although use of organs, tissues, or cells from different species is being investigated as an alternative treatment. The object of this study was to use xeno-transplantation of cultured pig chondrocytes for the repair of rabbit chondral defects, and to analyze the significance of tissue rejection in this animal model. Partial chondral defects, including removal of cartilage tissue and a part of the subchondral bone, were created in the lateral femoral condyles of 30 adult New Zealand White rabbits. A periosteal flap was sutured to the native cartilage with the cambium layer facing the defect. As a control, culture medium was injected into the defect void of one group of rabbits while in a treatment group, chondrocytes, isolated from normal femoral pig cartilage, were injected into the defect void. All rabbits were killed by 24 weeks. Macroscopic changes of the cartilage were analyzed using Mankin's score. The distal femoral portion was studied histologically using hematoxylin and eosin, alcian blue, toluidine blue, and Mason's trichrome. Pig cells and pig genetic material were detected in the neo-synthesized tissue by immunohistochemical detection of SLA-II-DQ and polymerase chain reaction analysis of the gene SLA-II-DQB. The synovial membrane was studied histologically by hematoxylin and eosin staining. In the control group, on average, less than 25 percent of the chondral defect was filled. The repair tissue had an irregular surface with few cells similar to chondrocytes or fibroblasts and a minimal formation of extracellular matrix. In the treatment group, the chondral defect was approximately 90 percent filled with good integration between the neo-synthesized cartilage and the native cartilage. The repair tissue had a smooth surface with cells similar to chondrocytes and a hyaline-like extracellular matrix. The neo-synthesized cartilage was morphologically similar to hyaline cartilage. Importantly, there were no signs of graft-vs.-host rejections or infiltration by immune cells. In the neo-synthesized tissue, pig genetic material was detected in 27 +/- 5 percent of all cells. These cells containing pig genetic material were distributed throughout the neo-synthesized cartilage. We conclude that the xeno-transplantation of chondrocytes could be an alternative method for the repair of articular cartilage defects.