Timing the therapeutic window of opportunity in early rheumatoid arthritis: proposal for definitions of disease duration in clinical trials.

The effects of treatment in early rheumatoid arthritis (RA) and the consequences of delayed therapy represent important areas for research. The concept of a 'window of opportunity' is now well established and considerable attention has been paid to when it might close. However, in order to study how long the window of opportunity lasts, the timing of its opening must be precisely defined. An analysis of definitions of 'onset' in clinical studies reveals imprecision and heterogeneity, making accurate assessment of this important concept of the 'window of opportunity' very difficult. In this paper we propose that, in clinical trials in early RA, data on durations since onset of symptoms and onset of joint swelling as well as disease duration based on fulfilment of classification criteria should be routinely presented.

Angiogenesis and blood vessel stability in inflammatory arthritis.

OBJECTIVE: To assess blood vessel stability in inflammatory synovial tissue (ST) and to examine neural cell adhesion molecule (NCAM), oxidative DNA damage, and hypoxia in vivo. METHODS: Macroscopic vascularity and ST oxygen levels were determined in vivo in patients with inflammatory arthritis who were undergoing arthroscopy. Vessel maturity/stability was quantified in matched ST samples by dual immunofluorescence staining for factor VIII (FVIII)/alpha-smooth muscle actin (alpha-SMA). NCAM and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) were examined by immunohistochemistry. Angiogenesis was assessed in vitro, using human dermal endothelial cells (HDECs) in a Matrigel tube formation assay. RESULTS: A significant number of immature vessels (showing no pericyte recruitment) was observed in tissue from patients with inflammatory arthritis (P < 0.001), in contrast to osteoarthritic and normal tissue, which showed complete recruitment of pericytes. Low in vivo PO(2) levels in the inflamed joint (median [range] 22.8 [3.2-54.1] mm Hg) were inversely related to increased macroscopic vascularity (P < 0.04) and increased microscopic expression of FVIII and alpha-SMA (P < 0.04 and P < 0.03, respectively). A significant proportion of vessels showed focal expression of NCAM and strong nuclear 8-oxodG expression, implicating a loss of EC-pericyte contact and increased DNA damage, levels of which were inversely associated with low in vivo PO(2) (P = 0.04 for each comparison). Circulating cells were completely negative for 8-oxodG. Exposure of HDEC to 3% O(2) (reflecting mean ST in vivo measurements) significantly increased EC tube formation (P < 0.05). CONCLUSION: Our findings indicate the presence of unstable vessels in inflamed joints associated with hypoxia, incomplete EC-pericyte interactions, and increased DNA damage. These changes may further contribute to persistent hypoxia in the inflamed joint to further drive this unstable microenvironment.

Long-term remission and biologic persistence rates: 12-year real-world data.

BACKGROUND: Biologic therapies have greatly improved outcomes in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Yet, our ability to predict long-term remission and persistence or continuation of therapy remains limited. This study explores predictors of remission and persistence of the initial biologic therapy in patients after 12 years. Furthermore, outcomes with adalimumab and etanercept are compared. PATIENTS AND METHODS: RA and PsA patients were prospectively recruited from a biologic clinic. Outcomes on commencing therapy, at 1 year and 12 years were reviewed. Demographics, medications, morning stiffness, patient global health score, tender and swollen joint counts, antibody status, CRP and HAQ were collected. Outcomes at 1 year and 12 years are reported and predictors of biologic persistence and EULAR-defined remission (DAS28-CRP < 2.6) are examined with univariate and multivariate analysis. RESULTS: A total of 403 patients (274 RA and 129 PsA) were analysed. PsA patients were more likely to be male, in full-time employment and have completed higher education. PsA had higher remission rates than RA at both 1 year (60.3% versus 34.5%, p < 0.001) and 12 years (91.3% versus 60.6%, p < 0.001). This difference persisted when patients were matched for baseline disease activity (p < 0.001). Biologic continuation rates were high for RA and PsA at 1 year (49.6% versus 58.9%) and 12 years (38.2% versus 52.3%). In PsA, patients starting on etanercept had lower CRP at 12 years (p = 0.041). Multivariate analysis showed 1-year continuation [OR 4.28 (1.28-14.38)] and 1-year low-disease activity [OR 3.90 (95% CI 1.05-14.53)] was predictive of a 12-year persistence. Persistence with initial biologic at 12 years [OR 4.98 (95% CI 1.83-13.56)] and male gender [OR 4.48 (95% CI 1.25-16.01)] predicted 12 year remission. CONCLUSIONS: This is the first study to show better response to biologic therapy in PsA compared to RA at 12 years. Long-term persistence with initial biologic agent was high and was predicted by biologic persistence and low-disease activity at 1 year. Interestingly, PsA patients had higher levels of employment, educational attainment, and long-term remission rates compared to RA patients.

The effects of alcohol consumption and its associations with disease activity among 979 patients with inflammatory arthritis.

OBJECTIVE: The role of alcohol in inflammatory disease remains debated. This study explores the relationship between alcohol and disease activity in patients with inflammatory arthritis. METHODS: Patients attending a rheumatology clinic between 2010 and 2020 were prospectively followed. Information on demographics, alcohol use, smoking habits and disease outcome measures were collected from these patients. Statistical analysis included univariate and multivariate linear and binary logistic regressions, Mann-Whitney U tests and one-way analysis of variance with Tukey's honest significant difference (HSD) test. RESULTS: Of the 979 analysed patients, 62% had rheumatoid arthritis (RA), 26.7% had psoriatic arthritis (PsA) and 11.2% had ankylosing spondylitis. Mean DAS28-CRP (Disease Activity Score 28 - C-reactive protein) in RA and PsA at 1 year was 2.96±1.39, and 64.2% of patients were in remission (DAS28-CRP ≤2.6 or BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) ≤4). Both male gender and risky drinking (>15 units of weekly alcohol) were significantly associated with remission. Compared with women, men had an OR of 1.8 (1.1, 2.5) (p=0.034) for any alcohol consumption and 6.9 (4.7, 9.1) (p=0.001) for drinking at least 15 weekly drinks. When adjusted for gender, there was no association between alcohol and disease activity. Yet, when adjusted for alcohol consumption, gender still significantly influenced disease activity. CONCLUSION: While it may appear that alcohol is linked to remission in inflammatory arthritis, when adjusted for gender, it is not. Men with inflammatory arthritis drink significantly more than women and have less severe disease activity.

Psoriatic arthritis management update - biotherapeutic options.

Psoriatic arthritis (PsA) is a seronegative spondyloarthropathy (SpA) occurring in up to 30% of patients with psoriasis. It has a wide variation of annual incidence (median 6.4, range 0.1-3.1 per 10(5) people), based on analysis of 13 incidence and prevalence reviews published between 1987 and December 2006. Conventional treatments with antiinflammatory and disease modifying or antirheumatic drugs are not efficacious in all patients, in particular those with axial disease. This review examines new pharmacological developments in the treatment of PsA with a focus on biologic therapies.

Toll-like receptor 2 induced angiogenesis and invasion is mediated through the Tie2 signalling pathway in rheumatoid arthritis.

BACKGROUND: Angiogenesis is a critical early event in inflammatory arthritis, facilitating leukocyte migration into the synovium resulting in invasion and destruction of articular cartilage and bone. This study investigates the effect of TLR2 on angiogenesis, EC adhesion and invasion using microvascular endothelial cells and RA whole tissue synovial explants ex-vivo. METHODS: Microvascular endothelial cells (HMVEC) and RA synovial explants ex vivo were cultured with the TLR2 ligand, Pam3CSK4 (1 µg/ml). Angiopoietin 2 (Ang2), Tie2 and TLR2 expression in RA synovial tissue was assessed by immunohistology. HMVEC tube formation was assessed using Matrigel matrix assays. Ang2 was measured by ELISA. ICAM-1 cell surface expression was assessed by flow cytometry. Cell migration was assessed by wound repair scratch assays. ECM invasion, MMP-2 and -9 expression were assessed using transwell invasion chambers and zymography. To examine if the angiopoietin/Tie2 signalling pathway mediates TLR2 induced EC tube formation, invasion and migration assays were performed in the presence of a specific neutralising anti-Tie2mAb (10 ug/ml) and matched IgG isotype control Ab (10 ug/ml). RESULTS: Ang2 and Tie2 were localised to RA synovial blood vessels, and TLR2 was localised to RA synovial blood vessels, sub-lining infiltrates and the lining layer. Pam3CSK4 significantly increased angiogenic tube formation (p<0.05), and upregulated Ang2 production in HMVEC (p<0.05) and RA synovial explants (p<0.05). Pam3CSK4 induced cell surface expression of ICAM-1, from basal level of 149±54 (MFI) to 617±103 (p<0.01). TLR-2 activation induced an 8.8±2.8 fold increase in cell invasion compared to control (p<0.05). Pam3CSK4 also induced HMVEC cell migration and induced MMP-2 and -9 from RA synovial explants. Neutralisation of the Ang2 receptor, Tie2 significantly inhibited Pam3CSK4-induced EC tube formation and invasion (p<0.05). CONCLUSION: TLR2 activation promotes angiogenesis, cell adhesion and invasion, effects that are in part mediated through the Tie2 signalling pathway, key mechanisms involved in the pathogenesis of RA.

IL-17A expression is localised to both mononuclear and polymorphonuclear synovial cell infiltrates.

INTRODUCTION: This study examines the expression of IL-17A-secreting cells within the inflamed synovium and the relationship to in vivo joint hypoxia measurements. METHODS: IL-17A expression was quantified in synovial tissue (ST), serum and synovial fluid (SF) by immunohistochemistry and MSD-plex assays. IL-6 SF and serum levels were measured by MSD-plex assays. Dual immunofluorescence for IL-17A was quantified in ST CD15+ cells (neutrophils), Tryptase+ (mast cells) and CD4+ (T cells). Synovial tissue oxygen (tpO(2)) levels were measured under direct visualisation at arthroscopy. Synovial infiltration was assessed using immunohistochemistry for cell specific markers. Peripheral blood mononuclear and polymorphonuclear cells were isolated and exposed to normoxic or 3% hypoxic conditions. IL-17A and IL-6 were quantified as above in culture supernatants. RESULTS: IL-17A expression was localised to mononuclear and polymorphonuclear (PMN) cells in inflamed ST. Dual immunoflourescent staining co-localised IL-17A expression with CD15+ neutrophils Tryptase+ mast cells and CD4+T cells. % IL-17A positivity was highest on CD15+ neutrophils, followed by mast cells and then CD4+T-cells. The number of IL-17A-secreting PMN cells significantly correlated with sublining CD68 expression (r = 0.618, p<0.01). IL-17A SF levels correlated with IL-6 SF levels (r = 0.675, p<0.01). Patients categorized according to tp0(2)< or >20 mmHg, showed those with low tp0(2)<20 mmHg had significantly higher IL-17A+ mononuclear cells with no difference observed for PMNs. Exposure of mononuclear and polymorphonuclear cells to 3% hypoxia, significantly induced IL-6 in mononuclear cells, but had no effect on IL-17A expression in mononuclear and polymorphonuclear cells. CONCLUSION: This study demonstrates IL-17A expression is localised to several immune cell subtypes within the inflamed synovial tissue, further supporting the concept that IL-17A is a key mediator in inflammatory arthritis. The association of hypoxia with Il-17A expression appears to be indirect, probably through hypoxia-induced pro-inflammatory pathways and leukocyte influx within the joint microenvironment.

Blockade of Toll-like receptor 2 prevents spontaneous cytokine release from rheumatoid arthritis ex vivo synovial explant cultures.

INTRODUCTION: The aim of this study was to examine the effect of blocking Toll-like receptor 2 (TLR2) in rheumatoid arthritis (RA) synovial cells. METHODS: RA synovial tissue biopsies, obtained under direct visualization at arthroscopy, were established as synovial explant cultures ex vivo or snap frozen for immunohistology. Mononuclear cell cultures were isolated from peripheral blood and synovial fluid of RA patients. Cultures were incubated with the TLR1/2 ligand, Pam3CSK4 (200 ng, 1 and 10 µg/ml), an anti-TLR2 antibody (OPN301, 1 µg/ml) or an immunoglobulin G (IgG) (1 µg/ml) matched control. The comparative effect of OPN301 and adalimumab (anti-tumour necrosis factor alpha) on spontaneous release of proinflammatory cytokines from RA synovial explants was determined using quantitative cytokine MSD multiplex assays or ELISA. OPN301 penetration into RA synovial tissue explants cultures was assessed by immunohistology. RESULTS: Pam3CSK4 significantly upregulated interleukin (IL)-6 and IL-8 in RA peripheral blood mononuclear cells (PBMCs), RA synovial fluid mononuclear cells (SFMCs) and RA synovial explant cultures (P < 0.05). OPN301 significantly decreased Pam3CSK4-induced cytokine production of tumour necrosis factor alpha (TNF-α), IL-1ß, IL-6, interferon (IFN)-γ and IL-8 compared to IgG control in RA PBMCs and SFMCs cultures (all P < 0.05). OPN301 penetration of RA synovial tissue cultures was detected in the lining layer and perivascular regions. OPN301 significantly decreased spontaneous cytokine production of TNF-α, IL-1ß, IFN-γ and IL-8 from RA synovial tissue explant cultures (all P < 0.05). Importantly, the inhibitory effect of OPN on spontaneous cytokine secretion was comparable to inhibition by anti-TNFα monoclonal antibody adalimumab. CONCLUSIONS: These findings further support targeting TLR2 as a potential therapeutic agent for the treatment of RA.

Remission in psoriatic arthritis: is it possible and how can it be predicted?

INTRODUCTION: Since remission is now possible in psoriatic arthritis (PsA) we wished to examine remission rates in PsA patients following anti tumour necrosis factor alpha (TNFalpha) therapy and to examine possible predictors of response. METHODS: Analysis of a prospective patient cohort attending a biologic clinic, between November 2004 and March 2008, was performed prior to commencing therapy and at regular intervals. Baseline clinical characteristics including demographics, previous disease-modifying antirheumatic drug (DMARD) response, tender and swollen joint counts, early morning stiffness, pain visual analogue score, patient global assessment, C reactive protein (CRP) and health assessment questionnaire (HAQ) were collected. RESULTS: A total of 473 patients (152 PsA; 321 rheumatoid arthritis (RA)) were analyzed. At 12 months remission, defined according to the disease activity score using 28 joint count and CRP (DAS28-CRP), was achieved in 58% of PsA patients compared to 44% of RA patients, significant improvement in outcome measures were noted in both groups (P<0.05). Analysis of a subgroup of PsA and RA patients matched for DAS28-CRP at baseline also showed higher numbers of PsA patients achieving remission. Linear regression analysis identified the HAQ at baseline as the best predictor of remission in PsA patients (P<0.001). CONCLUSIONS: DAS28 remission is possible in PsA patients at one year following anti-TNF therapy, at higher rates than in RA patients and is predicted by baseline HAQ.