L Cozzi

Early phenotypic activation of circulating helper memory T cells in scleroderma: correlation with disease activity.

OBJECTIVES--The differential expression of several accessory/activation molecules (CD26, CD29, CD45RA, CD25, MLR4, HLA-DR) on peripheral blood CD4+ and CD8+ T lymphocytes in patients with scleroderma was compared with that in controls and patients with other connective systemic diseases to look for evidence of the involvement of T cells in the disease process of scleroderma. METHODS--The two colour expression of surface molecules by circulating T cells was analysed with a panel of monoclonal antibodies and flow cytometry in 17 patients with scleroderma, 10 patients with systemic lupus erythematosus, and five patients with rheumatoid arthritis, and the results compared with those for 10 normal controls. The two colour T CD4+ phenotype was further compared between patients with active and quiescent disease in these patients with scleroderma. The coexpression of surface molecules by CD4+ T cells was also analysed by three colour flow cytometry in eight patients with scleroderma. RESULTS--Patients with scleroderma showed increased CD4+CD26+ and CD4+CD25+ percentages and absolute numbers and decreased CD8+CD29+ percentages compared with controls. Moreover, a significant correlation between the higher CD4+CD26+ T cell percentage and absolute cell numbers with disease activity was observed. Most of the CD4+ peripheral blood T cells from patients with scleroderma showed the CD26+CD45RA- phenotype by three colour flow cytometry analysis. CONCLUSIONS--The distinctive pattern of early helper memory T cell activation in these patients with rapidly evolving scleroderma supports the role of a T cell mediated mechanism in the progression of scleroderma.

Co-stimulatory modulation in rheumatoid arthritis: The role of (CTLA4-Ig) abatacept

Associations between rheumatoid arthritis (RA) susceptibility and polymorphism in multiple immunoregulatory genes suggest a role of altered T cell function in the disease. The growing relevance of the oxidative stress in RA synovitis, which results in a number of T cell signalling abnormalities, is reinforced by the demonstration of a direct NO inducing activity through the shared epitope of the HLA class II molecules HLA-DRbeta1, with secondary lymphocytes oxidative damage. Direct T cell/macrophage contact-dependent activation, one of the driving mechanisms of synovitis, is mediated by co-stimulatory molecules as well as cell membrane cytokines and may also result in an impaired suppressive function of T regulatory cells (Treg) in RA joints. The fusion of CTLA4 extracellular binding domain to the Fcgamma1 allows to obtain a soluble CTLA4 receptor, the dimeric recombinant human fusion protein abatacept (CTLA4-Ig). The improved knowledge of the CTLA4-B7 co-stimulation regulatory mechanisms by signals delivered into DCs and Tregs provides multiple potential targets for the abatacept treatment. CTLA4-Ig shows the capacity, either ex vivo or in vivo, to interrupt at multiple steps the ongoing inflammatory and destructive process, and to concur in restoring the immunoregulatory balance in RA.

Synovial effusion and synovial fluid biomarkers in psoriatic arthritis to assess intraarticular tumor necrosis factor-α blockade in the knee joint.

IntroductionThe purpose of this study was theevaluation of synovial effusion (SE), synovial fluid (SF) and synovial tissue (ST) biomarkers in relation to disease activity indexes to assess the response to intraarticular (IA) tumor necrosis factor (TNF)-α blockers in psoriatic arthritis (PsA).MethodsSystemic and local disease activity indexes (disease activity score (DAS); the Ritchie articular index (mRAI), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP); Thompson articular (THOMP) and joint articular (KJAI)-Index ) and ST samples were assessed at baseline, throughout treatment, and during the follow-up in 14 patients affected with PsA who underwent IA injections (0.5 ml to 12.5 mg) in the knee joint of etanercept (E) or placebo (P) once every two weeks for a 10-week period. Total SF white blood cell (WBC) counts (WBC/μl) and SF cytokine/chemokine (CK/CCK) levels were measured before IA-E at baseline, after IA-E, and as long as there were adequate amounts of SF for knee aspiration (post). Characterization of synovial mononuclear cell infiltration and synovial vessels was carried out in 8 out of 14 knees by staining serial sections of synovial tissue biopsies for CD45, CD3, CD68, CD31 and CD105.ResultsAt baseline, CRP and/or ESR were significantly correlated with SF-CK (interleukin- (IL-)1β, IL-1Ra, IL-6, IL-8) and CCK (CCL3). Post-IA injections, there was a decrease in SE in the knees in which aspiration following IA-E injection was possible as well as a significant reduction in SF WBC/μl and in SF-CK (IL-1β, IL-1Ra, IL-6 and IL-22). Pre- and post-IA-E injections, there were significant correlations between ST markers and SF-CK (IL-1β with CD45; IL-1β and IL-6 with CD31) and between SF-CCK (CCL4 and CCL3 with CD3). At the end of the study, there was a significant reduction in disease activity indexes (CRP, DAS, RAI, THOMP, KJAI) as well as in the ST markers (CD45; CD3).ConclusionsSynovial effusion regression is a reliable indicator of the response to IA TNF-α blockers in PsA patients as it is confirmed by the correlation between SF biomarkers to disease activity and synovial tissue inflammation.

Blockade of intra-articular TNF in peripheral spondyloarthritis: its relevance to clinical scores, quantitative imaging and synovial fluid and synovial tissue biomarkers.

OBJECTIVES This open-label study is based on a translational approach with the aim of detecting changes in the clinical condition as well as in imaging and synovial biological markers in both synovial fluid (SF) and synovial tissue (ST) in peripheral spondyloarthritis (SpA) patients following intra-articular (IA) blockade of TNF-α by serial etanercept injections. METHODS Twenty-seven SpA patients with resistant knee synovitis underwent four biweekly IA injections of etanercept (E) (12.5 mg). The primary outcome of Thompsons Knee Index (THOMP), and secondary outcomes of Knee Joint Articular Index (KJAI), C-reactive protein (CRP), HAQ-Disability Index (HAQ-DI), maximal synovial thickness (MST) according to ultrasonography (US) and contrast-enhanced magnetic resonance (C+MR) imaging, ST-CD45+ mononuclear cells (MNC) and ST-CD31+ vessels, IL-1β, IL-1Ra and IL-6 levels in SF were assessed at baseline and at the end of the study. RESULTS At the study end, clinical and imaging outcomes as well as ST and SF biological markers were significantly reduced compared to baseline. There were significant correlations between clinical, imaging and biological markers (CRP with either THOMP, or KJAI, or HAQ-DI or SF-IL-1Ra; US-MST with KJAI, ST-CD45+ with either THOMP, or KJAI, or ST-CD31+, or SF-IL-1β; SF-IL-6 with either THOMP, or KJAI, or SF-IL-1β, or IL-1Ra). CONCLUSIONS The proof of concept study revealed early improvement either in local and systemic clinical scores, in synovial thickness measures by C+MR and US, or expression of synovial biological markers. CD45+, CD31+ in ST and IL-6 and IL-1β in SF may be considered potential biomarkers of the peripheral SpA response to IA TNF-α blocking.

Molecular pathways involved in synovial cell inflammation and tumoral proliferation in diffuse pigmented villonodular synovitis.

Diffuse-type tenosynovial giant cell tumors, also known as pigmented villonodular synovitis, are unique mesenchymal lesions that arise from the synovial tissue of the joints. They are predominantly intraarticular, aggressive, infiltrative processes, characterized by both inflammatory or neoplastic properties and local destructive progression. The pattern of synovial gene and protein expressions in pigmented villonodular synovitis, similar to those in activated macrophages in rheumatoid arthritis, and the phenotype of multinucleated giant cells, characteristic of osteoclasts, suggest that there is a common autocrine mechanism in osteoclast differentiation in both diseases and indicate the potential utility of tumor necrosis factor (TNF)-alpha blockade. High synovial colony stimulating factor 1 (CSF1) messenger RNA (m RNA) expression in pigmented villonodular synovitis, unrelated to a chromosomal translocation involving CSF1 locus, may indicate that there is a synergic paracrine loop mediated by TNF-alpha and CSF1, as shown in both inflammatory and neoplastic conditions. The effects of a new therapeutic approach consisting in intraarticular TNF-alpha blockade were studied in four pigmented villonodular synovitis knees. Knee injections produced a rapid reduction in clinical and sonographic indexes and immunohistological alterations, confirmed by arthroscopic synovectomy. A delayed relapse in one of the four knees and unaltered synovial CSF1 expression were other important findings. In the light of these observations, CSF1/CSF1R interaction probably represents a more sensible therapeutic target than TNF-alpha blockade in the diffuse form of pigmented villonodular synovitis.

Synovial biomarkers in psoriatic arthritis.

Objective. To find candidate biomarkers of psoriatic arthritis (PsA). A panel of synovial fluid (SF) and synovial tissue (ST) biomarkers was analyzed in patients with resistant peripheral PsA, in relation to clinical and imaging outcomes of synovitis response following serial intraarticular (IA) etanercept injections (12.5 mg). Methods. Fourteen PsA patients with resistant knee joint synovitis were treated with 4 IA etanercept injections in a single knee joint, once every 2 weeks. Primary outcome (Thompson’s knee index: THOMP) and secondary outcomes were assessed at baseline and end of study: C-reactive protein, Knee Joint Articular Index (KJAI), Health Assessment Questionnaire disability index, maximal synovial thickness (MST) by gray-scale ultrasonography, contrast-enhanced magnetic resonance imaging (C+MRI), ST-cluster differentiation (CD)45+ mononuclear cell, ST-CD31+ vessels, and ST-CD105+ angiogenic endothelial cells, along with levels of SF interleukin 1ß (IL-1ß), IL-1 receptor antagonist (Ra), and IL-6. Results. At the end of the study, clinical and imaging outcomes, ST and SF biological markers were significantly reduced compared to baseline. There was a significant association between IL-6 and either THOMP or KJAI; between either ST-CD31+ or ST-CD105+ or ST-CD45+; between ST and SF biomarkers expression (CD45+ and IL-1ß) and between ST-CD45+ and both KJAI and MRI-MST. Comparing pre- versus post-IA etanercept injection changes (Δ), Δ IL-1ß was significantly correlated with both Δ IL-6 and with Δ IL-1Ra and Δ IL-6 with Δ IL-1Ra. Conclusion. The association to disease activity and the changes following IA treatment indicate that ST-CD45+ and ST-CD31+, along with SF-IL-6 and SF-IL-1ß, may represent candidate biomarkers of the knee synovitis response to IA tumor necrosis factor-α blockade.

AB0518 Synovial biomarkers in peripheral spondyloarthritis.

Objectives To analyse a panel of synovial fluid (SF) and synovial tissue (ST) biological markers expression at single joint level to find candidate biomarkers in resistant peripheral spondyloarthritis (SpA). Methods Twenty seven resistant SpA patients with knee joint synovitis, included in an Intra-articular (IA) TNF alpha blocking open-label study1, were treated with biweekly four IA Etanercept injections (12.5 mg) in a single knee joint. The primary outcome (Thompson’s knee index: THOMP) and secondary outcomes were assessed at baseline and at week 8 of the study. The secondary outcomes are: C-reactive protein; Knee Joint Articular Index (KJAI), Health Assessment Questionnaire disability index (HAQ-DI), maximal synovial thickness by gray-scale ultrasonography (US-MST), synovial tissue cluster differentiation CD45+ mononuclear cell (ST-CD45+), synovial tissue-CD31+ vessels (ST-CD31+), and along with levels of synovial fluid (SF) soluble inflammation makers such as Interleukin 1ß (SF-IL 1ß), Interleukin 1 Receptor antagonist (SF-IL 1Ra) and Interleukin 6 (SF-IL 6). Results At the end of the study, composite clinical indexes, US-MST, ST and SF biological markers were significantly reduced compared to baseline. There was a significant correlation between CRP and THOMP, or KJAI, or HAQ-DI, or SF-IL 1Ra; between KJAI and THOMP or US-MST; between ST-CD45+ and THOMP, or KJAI or ST-CD31+, or SF-IL 1ß; between SF-IL 6 and THOMP, or KJAI, or SF-IL 1ß, or SF-IL 1Ra; between SF-IL 1 Ra and SF-IL 1ß. Comparing pre- versus post-IA Etanercept injection changes (Δ), we found a significant correlation between ΔCRP with ΔSF-IL 1ß, ΔKJAI with ΔTHOMP and ΔSF-IL 6; Δ HAQ with ΔSF-IL 6; ΔST-CD-45+ with ΔSF-IL 1ß; ΔSF-IL 6 and ΔSF-IL 1ß; ΔSF-IL 1Ra with ΔSF-IL 1ß and ΔSF-IL 6. Conclusions The significant association at single joint level of composite clinical indexes to inflammatory soluble markers and to synovial tissue marker expression, as well as between clinical and synovial biomarkers changes following IA-anti TNF-alpha blockers treatment, suggest that CD45+ in synovial tissue and IL-6 and IL-1β in SF may be considered potential biomarkers of the peripheral SpA response to IA TNF- alpha blocking. References Fiocco U. et al: Synovial Biomarkers in Psoriatic Arthritis. J Rheumatol Suppl. 2012 Jul;89:61-4. doi: 10.3899/jrheum.120246 Disclosure of Interest None Declared