Marie-Joëlle Kaiser

Increased matrix metalloproteinase-3 serum levels in rheumatic diseases: relationship with synovitis and steroid treatment

Objective: To determine matrix metalloproteinase-3 (MMP-3) serum levels in patients with rheumatic diseases and to study the relation between MMP-3 and C reactive protein (CRP) levels. Methods: MMP-3 serum levels were determined by enzyme linked immunosorbent assay (ELISA) in (a) patients with active inflammatory rheumatic diseases: rheumatoid arthritis (RA), psoriatic arthritis, polymyalgia rheumatica, acute crystal arthritis, and ankylosing spondylitis; (b) patients with active inflammatory systemic diseases: cutaneo-articular or renal systemic lupus erythematosus (SLE), systemic sclerosis, and vasculitides; (c) patients with non-inflammatory rheumatic diseases: osteoarthritis and fibromyalgia; (d) critically ill patients without rheumatic diseases, representing an acute inflammatory control group; (e) healthy controls. Results: MMP-3 serum levels were significantly increased in patients with active RA, psoriatic arthritis, and polymyalgia rheumatica, whether treated or not by corticosteroids, and in female patients with acute crystal arthritis. MMP-3 serum levels were normal in steroid-free patients with active cutaneo-articular or renal SLE, systemic sclerosis, and vasculitides but were significantly increased in steroid treated patients. MMP-3 levels were normal in fibromyalgia, osteoarthritis, ankylosing spondylitis, and acute inflammatory controls. MMP-3 was significantly correlated with CRP in RA (r=0.5, p=0.0004) but not in any of the other disease groups. Conclusions: MMP-3 serum levels are increased in inflammatory rheumatic diseases characterised by joint synovitis, such as RA, polymyalgia rheumatica, psoriatic arthritis, and acute crystal arthritis—that is, whether the diseases are acute or chronic, erosive or not. They are normal in SLE, systemic sclerosis, and vasculitides as well as in non-rheumatic inflammatory controls, but are significantly increased by steroids. These data strongly suggest that serum MMP-3 reflects synovial inflammation.

(18)F-FDG PET imaging of rheumatoid knee synovitis correlates with dynamic magnetic resonance and sonographic assessments as well as with the serum level of metalloproteinase-3.

PurposeThe aim of this study was to assess rheumatoid arthritis (RA) synovitis with positron emission tomography (PET) and 18F-fluorodeoxyglucose (18F-FDG) in comparison with dynamic magnetic resonance imaging (MRI) and ultrasonography (US).MethodsSixteen knees in 16 patients with active RA were assessed with PET, MRI and US at baseline and 4 weeks after initiation of anti-TNF-α treatment. All studies were performed within 4 days. Visual and semi-quantitative (standardised uptake value, SUV) analyses of the synovial uptake of FDG were performed. The dynamic enhancement rate and the static enhancement were measured after i.v. gadolinium injection and the synovial thickness was measured in the medial, lateral patellar and suprapatellar recesses by US. Serum levels of C-reactive protein (CRP) and metalloproteinase-3 (MMP-3) were also measured.ResultsPET was positive in 69% of knees while MRI and US were positive in 69% and 75%. Positivity on one imaging technique was strongly associated with positivity on the other two. PET-positive knees exhibited significantly higher SUVs, higher MRI parameters and greater synovial thickness compared with PET-negative knees, whereas serum CRP and MMP-3 levels were not significantly different. SUVs were significantly correlated with all MRI parameters, with synovial thickness and with serum CRP and MMP-3 levels at baseline. Changes in SUVs after 4 weeks were also correlated with changes in MRI parameters and in serum CRP and MMP-3 levels, but not with changes in synovial thickness.Conclusion18F-FDG PET is a unique imaging technique for assessing the metabolic activity of synovitis. The PET findings are correlated with MRI and US assessments of the pannus in RA, as well as with the classical serum parameter of inflammation, CRP, and the synovium-derived parameter, serum MMP-3. Further studies are warranted to establish the place of metabolic imaging of synovitis in RA.

15-deoxy-delta12,14-prostaglandin J2 inhibits Bay 11-7085-induced sustained extracellular signal-regulated kinase phosphorylation and apoptosis in human articular chondrocytes and synovial fibroblasts

We have previously shown that nuclear factor-κB inhibition by adenovirus expressing mutated IκB-α or by proteasome inhibitor increases human articular chondrocytes sensibility to apoptosis. Moreover, the nuclear factor-κB inhibitor BAY11-7085, a potent anti-inflammatory drug in rat adjuvant arthritis, is itself a proapoptotic agent for chondrocytes. In this work, we show that BAY 11-7085 but not the proteasome inhibitor MG-132 induced a rapid and sustained phosphorylation of extracellular signal-regulated kinases (ERK1/2) in human articular chondrocytes. The level of ERK1/2 phosphorylation correlated with BAY 11-7085 concentration and chondrocyte apoptosis. 15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) and its precursor prostaglandin (PG) D2 but not PGE2 and PGF2α rescued chondrocytes from BAY 11-7085-induced apoptosis. 15d-PGJ2 markedly inhibited BAY 11-7085-induced phosphorylation of ERK1/2. BAY 11-7085 also induced ERK1/2 phosphorylation and apoptosis in human synovial fibroblasts, and these reactions were down-regulated by 15d-PGJ2. Further analysis in synovial fibroblasts showed that only molecules that suppressed BAY 11-7085-induced phosphorylation of ERK1/2 (i.e. 15d-PGJ2, PGD2, and to a lesser extent, MEK1/2 inhibitor UO126, but not prostaglandins E2 and F2α or peroxisome proliferator-activated receptor-γ agonist ciglitazone) were able protect cells from apoptosis. These results suggested that the antiapoptotic effect of 15d-PGJ2 on chondrocytes and synovial fibroblasts might involve inhibition of ERK1/2 phosphorylation.

Increased synovial fluid levels of soluble CD23 are associated with an erosive status in rheumatoid arthritis (RA)

Synovial fluid (SF) levels of soluble CD23 (sCD23) were determined in 96 patients presenting with an inflammatory knee effusion (73 with RA and 23 with reactive arthritis (ReA) serving as a control inflammatory non‐erosive group) and were correlated with the degree of joint destruction, with local immune parameters (IL‐1β, IL‐3, IL‐4, IL‐6, IL‐8, IL‐10, IL‐12 and sCD25) and with serum markers of inflammation, C‐reactive protein and erythrocyte sedimentation rate. RA patients, classified as erosive or not according to Larsen’s grade, were separated as follows: (i) 13 patients with non‐erosive RA; (ii) 16 RA patients with erosions in hands but not in knees, matched for disease duration with the first group; (iii) 44 RA patients with hand and knee erosions, matched with the second group for rheumatoid factor positivity but of longer disease duration. SF sCD23 levels were significantly increased in both erosive RA groups compared with non‐erosive diseases, whether RA or ReA (P < 0·05), whose SF levels were not different. SF IL‐10 showed a similar profile to that of SF sCD23 and was the only other parameter characteristic of erosive RA, but no direct correlation was found between the two. SF sCD23 was significantly correlated with IL‐12 (r = 0·65, P = 0·0001) and sCD25 (r = 0·39, P = 0·0019) exclusively in the two erosive RA populations. In conclusion, these data showing that increased levels of sCD23 are not only found in the SF of erosive joints but also in knee SF of patients with erosive RA but without knee x‐ray‐diagnosed erosions suggest that this parameter might be of predictive value for joint destruction. Longitudinal studies are however needed to confirm its potential clinical interest.

Longterm Followup of Rituximab Therapy in Patients with Rheumatoid Arthritis: Results from the Belgian MabThera in Rheumatoid Arthritis Registry

Objective. Our study reports the results of the MIRA (MabThera In Rheumatoid Arthritis) registry, set up to collect data about clinical usage, patient profile, and retention of rituximab (RTX) treatment in daily clinical practice in Belgium. Methods. Patients with active rheumatoid arthritis (RA) who failed at least 1 anti-tumor necrosis factor (anti-TNF) treatment were included in our study between November 2006 and October 2011. At baseline, demographics, medication, disease history, disease activity, rheumatoid factor (RF), and anticyclic citrullinated peptide antibodies (anti-CCP) status were recorded. Evolution of the 28-joint Disease Activity Score (DAS28)-erythrocyte sedimentation rate, retreatments, and reasons for therapy stop were followed prospectively. Results. The MIRA registry included 649 patients, with mean disease duration of 12.8 ± 0.4 years and DAS28 values at inclusion of 5.85 ± 0.48. Patients received on average 2.82 ± 0.07 (range 1–9) RTX treatments, over a mean followup period of 93.1 ± 2.6 weeks. At database lock, 433 patients (66.7%) were still under RTX treatment, 182 (28.0%) had stopped treatment, and 34 (5.2%) were lost to followup. Ineffectiveness (n = 108, 59%) and safety concerns (n = 39, 22%) were the most frequent reasons for discontinuing RTX therapy. From 2006 to 2011, RTX practice patterns clearly evolved toward RTX being started in patients with a lower number of previously failed anti-TNF drugs and lower baseline DAS28 values. A lower number of previous anti-TNF drugs, and positivity for RF and anti-CCP, predicted more successful longterm treatment. RTX treatment provided adequate longterm disease control. Conclusion. In our daily practice study, RTX provided good longterm disease control and treatment retention in refractory patients with RA. Over the years, rheumatologists tended to start this treatment in patients with fewer previous anti-TNF treatments and lower disease activity.

Peroxisome proliferator-activated receptor-gamma1 is dephosphorylated and degraded during BAY 11-7085-induced synovial fibroblast apoptosis.

Peroxisome proliferator-activated receptor-γ (PPAR-γ) plays a central role in whole body metabolism by regulating adipocyte differentiation and energy storage. Recently, however, PPAR-γ has also been demonstrated to affect proliferation, differentiation, and apoptosis of different cell types. As we have previously shown that BAY 11-7085-induced synovial fibroblast apoptosis is prevented by PPAR-γ agonist 15d-PGJ2; the expression of PPAR-γ in these cells was studied. Both PPAR-γ1 and PPAR-γ2 isoforms were cloned from synovial fibroblast RNA, but only PPAR-γ1 was detected by Western blot, showing constitutive nuclear expression. Within minutes of BAY 11-7085 treatment, a PPAR-γ1-specific band was shifted into a form of higher mobility, suggesting dephosphorylation, as confirmed by phosphatase treatment of cell extracts. Of interest, BAY 11-7085-induced PPAR-γ1 dephosphorylation was followed by PARP and caspase-8 cleavage as well as by PPAR-γ1 protein degradation. PPAR-γ1 dephosphorylation was followed by the loss of PPAR-DNA binding activity ubiquitously present in synovial fibroblast nuclear extracts. Unlike the phosphorylated form, dephosphorylated PPAR-γ1 was found in insoluble membrane cell fraction and was not ubiquitinated before degradation. PPAR-γ1 dephosphorylation coincided with ERK1/2 phosphorylation that accompanies BAY 11-7085-induced synovial fibroblasts apoptosis. 15d-PGJ2, PGD2, and partially UO126, down-regulated ERK1/2 phosphorylation, protected cells from BAY 11-7085-induced apoptosis, and reversed both PPAR-γ dephosphorylation and degradation. Furthermore, PPAR-γ antagonist BADGE induced PPAR-γ1 degradation, ERK1/2 phosphorylation, and synovial fibroblasts apoptosis. The results presented suggest an anti-apoptotic role for PPAR-γ1 in synovial fibroblasts. Since apoptotic marker PARP is cleaved after PPAR-γ1 dephosphorylation but before PPAR-γ1 degradation, dephosphorylation event might be enough to mediate BAY 11-7085-induced apoptosis in synovial fibroblasts.

Use of Tomosynthesis for Detection of Bone Erosions of the Foot in Patients With Established Rheumatoid Arthritis: Comparison With Radiography and CT

OBJECTIVE The purpose of this study was to compare tomosynthesis with radiography for the detection of bone erosions of the foot in patients with established rheumatoid arthritis (RA) using MDCT as a reference standard. SUBJECTS AND METHODS Eighteen consecutive patients with established RA were included. Each patient underwent radiography, tomosynthesis, and CT examinations of the feet on the same day. Two radiologists independently determined the number of bone erosions and the Sharp-van der Heijde score with each of the three imaging modalities. RESULTS On a total of 216 joints from 18 patients, 216 bone erosions were detected on CT, 215 on tomosynthesis, and 181 with radiography. The mean (± SD) Sharp-van der Heijde score was equivalent for tomosynthesis (18.8 ± 16.8) and CT (19.8 ± 18.5) but was statistically lower for radiography (16.4 ± 18.0) (p = 0.030). The respective overall sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for tomosynthesis were 80%, 75%, 78%, 76%, and 80%, whereas the respective corresponding values for radiography were 66%, 81%, 74%, 77%, and 71%. The radiation burden of tomosynthesis was almost equivalent to that of radiography. CONCLUSION Tomosynthesis has a higher sensitivity than radiography to detect bone erosions of the foot in patients with established RA and imparts an almost equivalent radiation burden.

Contrast-enhanced coded phase-inversion harmonic sonography of knee synovitis correlates with histological vessel density: 2 automated digital quantifications.

Objective. To use contrast-enhanced coded phase-inversion harmonic B-mode sonography to assess the acoustic enhancement of the synovial area of the knee; and to compare the data with the histological vessel density. Methods. Eleven patients eligible for a knee arthroscopy were studied. Acoustic quantification was carried out by a digital image analysis program that detects the time-dependent increase [intensity (time) = k × time + C] of gray-level intensity in all the pixels of a specific region of interest (ROI) following intravenous injection of the microbubble contrast agent sulfur hexafluoride. Echo-guided synovial biopsies were carried out in the same ROI. Synovial vessel areas were quantified after Factor VIII immunostaining of synovial biopsies using an automated digital image analysis. Results. Significant (p < 0.05) correlations were observed between histological vessel density and percentage of the synovial area with a k value > 0.01 (r = 0.93) and kmax values (r = 0.79), as well as between the 2 latter parameters (r = 0.72). The histological vessel density and the 2 acoustic parameters were also significantly correlated with the logarithm of erythrocyte sedimentation rate (r = 0.77, r = 0.87, r = 0.67, respectively) and with log C-reactive protein serum concentration (r = 0.69, r = 0.83, r = 0.62, respectively). Conclusion. Contrast-enhanced coded phase-inversion harmonic B-mode sonography coupled with an appropriate data analysis method is a new tool to identify and quantify vessel density in knee synovitis.