Objective:To investigate the synovial tissue in patients with rheumatoid arthritis (RA) treated with rituximab and to identify possible predictors of clinical response.Methods:A total of 24 patients with RA underwent synovial biopsy before, 4 and 16 weeks after initiation of rituximab treatment (without peri-infusional corticosteroids to prevent bias). Immunohistochemical analysis was performed and stained sections were analysed by digital image analysis. Linear regression analysis was used to identify predictors of clinical response.Results:The 28-joint Disease Activity Score (DAS28) was unaltered at 4 weeks, but significantly reduced at 16 and 24 weeks. Serum levels of IgM-rheumatoid factor (RF) decreased significantly at 24 weeks and anti-citrullinated peptide antibody (ACPA) levels at 36 weeks. Peripheral blood B cells were depleted at 4 weeks and started to return at 24 weeks. Synovial B cells were significantly decreased at 4 weeks, but were not completely depleted in all patients; there was a further reduction at 16 weeks in some patients. We found a significant decrease in macrophages at 4 weeks, which was more pronounced at 16 weeks. At that timepoint, T cells were also significantly decreased. The reduction of plasma cells predicted clinical improvement at 24 weeks.Conclusions:The results support the view that B cells orchestrate local cellular infiltration. The kinetics of the serological as well as the tissue response in clinical responders are consistent with the notion that rituximab exerts its effects in part by an indirect effect on plasma cells associated with autoantibody production, which could help explain the delayed response after rituximab treatment.Trial registration number: ISRCTN05568900.

Morphea, also known as localized scleroderma, encompasses a group of idiopathic sclerotic skin diseases. The spectrum ranges from relatively mild phenotypes, which generally cause few problems besides local discomfort and visible disfigurement, to subtypes with severe complications such as joint contractures and limb length discrepancies. Eosinophilic fasciitis (EF, Shulman syndrome) is often regarded as belonging to the severe end of the morphea spectrum. The exact driving mechanisms behind morphea and EF pathogenesis remain to be elucidated. However, extensive extracellular matrix formation and autoimmune dysfunction are thought to be key pathogenic processes. Likewise, these processes are considered essential in systemic sclerosis (SSc) pathogenesis. In addition, similarities in clinical presentation between morphea and SSc have led to many theories about their relatedness. Importantly, morphea may be differentiated from SSc based on absence of sclerodactyly, Raynaud’s phenomenon, and nailfold capillary changes. The diagnosis of morphea is often based on characteristic clinical findings. Histopathological evaluation of skin biopsies and laboratory tests are not necessary in the majority of morphea cases. However, full-thickness skin biopsies, containing fascia and muscle tissue, are required for the diagnosis of EF. Monitoring of disease activity and damage, especially of subcutaneous involvement, is one of the most challenging aspects of morphea care. Therefore, data harmonization is crucial for optimizing standard care and for comparability of study results. Recently, the localized scleroderma cutaneous assessment tool (LoSCAT) has been developed and validated for morphea. The LoSCAT is currently the most widely reported outcome measure for morphea. Care providers should take disease subtype, degree of activity, depth of involvement, and quality-of-life impairments into account when initiating treatment. In most patients with circumscribed superficial subtypes, treatment with topical therapies suffices. In more widespread disease, UVA1 phototherapy or systemic treatment with methotrexate (MTX), with or without a systemic corticosteroid combination, should be initiated. Disappointingly, few alternatives for MTX have been described and additional research is still needed to optimize treatment for these debilitating conditions. In this review, we present a state-of-the-art flow chart that guides care providers in the treatment of morphea and EF.

The synovium is the major target tissue of inflammatory arthritides such as rheumatoid arthritis (RA). The study of synovial tissue has advanced significantly over a number of decades from arthroplasty, blind needle biopsy and more recently facilitated by arthroscopic and ultrasonographic technology that allows easier visualisation and improves the reliability of obtaining synovial biopsies. The potential for study of pathogenesis, patient stratification, discovery of biomarkers and novel targets, as well as validation of therapy, have all been progressed rapidly in the last decade, facilitated by increasingly diverse and sophisticated analytical and technological approaches. In this review we describe clinical and translational developments in the field of synovial tissue research, outlining current and novel investigative technologies, and highlight their application to advance our understanding of the aforegoing imperatives.3

Objective. Atacicept is a recombinant fusion protein that binds and neutralizes B lymphocyte stimulator and a proliferation-inducing ligand. The purpose of this study was to investigate the tolerability, pharmacokinetics, and pharmacodynamics of atacicept treatment in patients with rheumatoid arthritis (RA) and to collect exploratory data on clinical outcomes.Methods. In this multicenter, phase Ib, randomized, placebo-controlled, dose-escalating trial, 73 patients were enrolled into 6 escalating-dose cohorts. Patients received atacicept or placebo as single doses (70, 210, or 630 mg) or as repeated doses given at 2-week intervals (3 doses of 70 mg, 3 doses of 210 mg, or 7 doses of 420 mg), followed by 10 weeks of trial assessments, with a followup assessment at 3 months after the final dose.Results. Atacicept was well tolerated, with few differences between treatment groups and no obvious safety concerns. The pharmacokinetics profile was nonlinear, but was consistent and predictable across all doses and regimens. Treatment-related decreases in immunoglobulin (particularly IgM) and rheumatoid factor levels were evident, and a clear decrease in anti-citrullinated protein antibodies was observed in the cohort that received 7 doses of 420 mg. The B cell response was biphasic, with an initial transient increase (dominated by memory B cells) followed by a doserelated decrease (dominated by mature B cells). Clinical assessments showed trends toward improvement with the 3-month treatment. Little effect on the erythrocyte sedimentation rate or C-reactive protein levels was seen.Conclusion. Atacicept was well tolerated both systemically and locally. The results demonstrated that the biologic activity of atacicept was consistent with its mechanism of action.

The association between rheumatoid arthritis (RA) and periodontal disease (PD) has been the focus of numerous investigations driven by their common pathological features. RA is an autoimmune disease characterized by chronic inflammation, the production of anti-citrullinated proteins antibodies (ACPA) leading to synovial joint inflammation and destruction. PD is a chronic inflammatory condition associated with a dysbiotic microbial biofilm affecting the supporting tissues around the teeth leading to the destruction of mineralized and non-mineralized connective tissues. Chronic inflammation associated with both RA and PD is similar in the predominant adaptive immune phenotype, in the imbalance between pro- and anti-inflammatory cytokines and in the role of smoking and genetic background as risk factors. Structural damage that occurs in consequence of chronic inflammation is the ultimate cause of loss of function and disability observed with the progression of RA and PD. Interestingly, the periodontal pathogen Porphyromonas gingivalis has been implicated in the generation of ACPA in RA patients, suggesting a direct biological intersection between PD and RA. However, more studies are warranted to confirm this link, elucidate potential mechanisms involved, and ascertain temporal associations between RA and PD. This review is mainly focused on recent clinical and translational research intends to discuss and provide an overview of the relationship between RA and PD, exploring the similarities in the immune-pathological aspects and the possible mechanisms linking the development and progression of both diseases. In addition, the current available treatments targeting both RA and PD were revised.