Interleukin 27 is a novel cytokine with anti-inflammatory effects against spondyloarthritis through the suppression of Th17 responses.

Introduction: Spondylarthritis (SpA) development in HLA-B27/human ß2-microglobulin transgenic rat (B27-rat) is correlated with altered conventional dendritic cell (cDC) function that promotes an inflammatory pattern of CD4+T cells, including a biased expansion of pro-inflammatory Th17 population and imbalance of regulatory T cells cytokine profile. Transcriptomic analysis revealed that cDCs from B27-rats under express IL-27, an anti-inflammatory cytokine which induces the differentiation of IL-10+ regulatory T cells and inhibits Th17 cells. Methods: Here, we first investigated whether in vitro addition of exogenous IL-27 could reverse the inflammatory pattern observed in CD4+ T cells. Next, we performed preclinical assay using IL-27 to investigate whether in vivo treatment could prevent SpA development in B27-rats. Results: in vitro addition of IL-27 to cocultures of cDCs and CD4+ T cell subsets from B27-rats reduced IL-17 and enhanced IL-10 production by T cells. Likewise, IL-27 inhibited the production of IL-17 by CD4+ T cells from SpA patients. Interestingly, in vivo treatment with recombinant IL-27 starting before SpA onset, inhibited SpA development in B27-rats through the suppression of IL-17/TNF producing CD4+ T cells. Discussion: Overall, our results reveal a potent inhibitory effect of IL-27 and highlight this cytokine as a promising new therapeutic target in SpA, especially for SpA patients non responders to currently approved biotherapies.

Remission and low disease activity in psoriatic arthritis publications: a systematic literature review with meta-analysis.

OBJECTIVES: Remission (REM) or low disease activity (LDA) is the treatment target in psoriatic arthritis (PsA). The objective of this study was to assess the reporting and prevalence of REM/LDA in published studies of PsA. METHODS: This was a systematic literature review of all clinical papers published in PubMed, EMBASE or Cochrane database in English between 2012 and 2019 in the field of PsA. Data were collected regarding reporting of REM/LDA by very low disease activity/minimal disease activity (VLDA/MDA), Disease Activity index for Psoriatic Arthritis (DAPSA), or Disease Activity Score 28 joints (DAS28). The pooled rates of REM and LDA by each definition were calculated by random effect meta-analysis. RESULTS: In all, 258 publications (corresponding to 114 651 patients), of which 81 (31%) were randomized controlled trials, were analysed: patients' mean age was 49.4 ( 4.4) years; with a mean disease duration of 8.5 ( 3.8) years. REM/LDA was reported in 91/258 (35.3%) publications. VLDA/MDA was used in 61/91 (67.0%) studies, DAPSA in 27/91 (29.6%) and DAS28 in 28/91 (30.7%), with 40/91 (43.9%) papers reporting several of these definitions. The pooled prevalence (lower-upper limits) of REM was 13.1% (10.9-15.4), 23.1% (16.8-30.1) and 42.1% (33.9-50.4) using VLDA, DAPSA-REM and DAS28, respectively. For LDA the pooled prevalence was 36.3% (32.3-40.5), 52.8% (41.8-63.6) and 60.4% (52.5-68.0) using MDA, DAPSA-LDA and DAS28, respectively. CONCLUSION: REM/LDA status was reported in only1/3 of recent studies on PsA, with important variations in the frequency of these outcomes according to the definition used: 13.1-42.1% for REM, and 36.3-60.4% for LDA. This highlights the need for consensus.

Increased rate of lumbar spondylolisthesis in rheumatoid arthritis: A case-control study.

OBJECTIVE: The aim of this study was to compare the prevalence of lumbar spondylolisthesis (SPL) in patients suffering from low back pain (LBP) with or without rheumatoid arthritis (RA) and to identify potential factors associated with SPL in patients with RA. METHODS: We performed a case-control study. Cases and control patients had chronic LBP (more than 4 weeks). Patient with RA fulfilled the 2010 ACR/EULAR criteria. The main outcome was the presence of lumbar SPL on lumbar X-ray. The prevalence of SPL between RA and control patients was compared using chi-squared test. Potential factors associated with SPL in patients with RA were investigated by univariate and multivariate analysis, estimating odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: A total of 67 cases and 83 controls were included. Median [interquartile range] age of patients with RA was 60.0 years [51.0-72.0]; 80.6% were females; and 92.5% and 83.6% were positive for anti-citrullinated protein antibodies (ACPAs) or rheumatoid factor, respectively. Mean RA disease duration was 11.2 ± 8.7 years. SPL was more frequent in patients with RA than controls (41.8% versus 18.1%, P = 0.001). Adjusted to gender, RA was associated with increased prevalence of SPL (OR 3.15 [95% CI 1.48-6.70], P = 0.003). Among patients with RA, SPL was mainly Grade 1 (85.7%). Multivariate analysis revealed SPL is associated with increased age in patients with RA (OR 1.06 [1.02-1.11], P = 0.004). CONCLUSION: In a population of patients with chronic LBP, the prevalence of lumbar SPL was higher with than without RA. SPL might be explained by synovitis of lumbar facet joints.