Rheumatoid arthritis: The benefits of early treatment after decades

Clinical Applications of Synovial Biopsy

The synovial tissue is a primary target of multiple diseases characterized by different pathogenic mechanisms, including infective, deposition, neoplastic, and chronic immune-inflammatory pathologies. Synovial biopsy can have a relevant role in differential diagnosis of specific conditions in clinical practice, although its exploitation remains relatively limited. In particular, no validated synovial-tissue-derived biomarkers are currently available in the clinic to aid in the diagnosis and management in most frequent forms of chronic inflammatory arthropathies, namely rheumatoid arthritis (RA) and the spondyloarthritides (SpA). In this brief review, we will discuss the current spectrum of clinical applications of synovial biopsy in routine rheumatologic care and will provide an analysis of the perspectives for its potential exploitation in patients with chronic inflammatory arthritides.

Real benefits of ultrasound evaluation of hand and foot synovitis for better characterisation of the disease activity in rheumatoid arthritis

Objectives

Optimal management of rheumatoid arthritis (RA) depends on accurate evaluation of disease activity. Foot synovitis is not included in the most used RA outcome measure (DAS-28 score). The aim of this study was to investigate how musculoskeletal ultrasound (MSK-US) examination of hand and feet correlate with the disease activity score (DAS-28 score). We also explored whether performing MSK-US assessments of hands alone compared with hands and feet underestimates the disease activity in RA.

Methods

This is a real-life cross-sectional study of 101 patients (51 with RA and 50 with other musculoskeletal conditions) with inflammatory small joint pain, who underwent MSK-US examination of hands and feet.

Results

MSK-US-detected hand synovitis was found in 18/51 (35.3%) RA patients and 16/50 (32%) of those with other musculoskeletal conditions (p = 0.96), while foot synovitis was detected in 18/51 (35.3%) and 12/50 (24%) patients, respectively (p = 0.78). DAS-28 did not correlate with any of the US outcome measures in patients with RA. Six out of 13 (46.1%) RA patients in remission, 7/14 (50%) with low disease activity and 18/32 (56.2%) with moderate disease activity (according to DAS-28 definition) had active synovitis as assessed by the MSK-US examination of their hands and feet. MSK-US-detected synovitis led to treatment escalation in 26/51 (51%) RA patients.

Conclusion

This study emphasises that MSK-US examination of hands and feet has led to optimised management of the majority of RA patients, which would have not been possible otherwise, because of the lack of correlation between DAS-28 assessment and MSK-US outcomes.

Key Points

• The most used disease activity score in rheumatoid arthritis (DAS-28) did not correlate with US outcome measures derived from hands and feet examination.

• DAS-28 did not differentiate between RA patients with subclinical active synovitis versus well-controlled disease on US.

• As a result of US examination of the hands and feet, 51% RA patients had their immunosuppressive treatment optimised.

Electronic supplementary material

The online version of this article (10.1007/s00330-019-06187-8) contains supplementary material, which is available to authorized users.

Targeting early changes in the synovial microenvironment: a new class of immunomodulatory therapy?

Objectives

Controlled immune responses rely on integrated crosstalk between cells and their microenvironment. We investigated whether targeting proinflammatory signals from the extracellular matrix that persist during pathological inflammation provides a viable strategy to treat rheumatoid arthritis (RA).

Methods

Monoclonal antibodies recognising the fibrinogen-like globe (FBG) of tenascin-C were generated by phage display. Clones that neutralised FBG activation of toll-like receptor 4 (TLR4), without impacting pathogenic TLR4 activation, were epitope mapped by crystallography. Antibodies stained synovial biopsies of patients at different stages of RA development. Antibody efficacy in preventing RA synovial cell cytokine release, and in modulating collagen-induced arthritis in rats, was assessed.

Results

Tenascin-C is expressed early in the development of RA, even before disease diagnosis, with higher levels in the joints of people with synovitis who eventually developed RA than in people whose synovitis spontaneously resolved. Anti-FBG antibodies inhibited cytokine release by RA synovial cells and prevented disease progression and tissue destruction during collagen-induced arthritis.

Conclusions

Early changes in the synovial microenvironment contribute to RA progression; blocking proinflammatory signals from the matrix can ameliorate experimental arthritis. These data highlight a new drug class that could offer early, disease-specific immune modulation in RA, without engendering global immune suppression.

Liquid biopsies to guide therapeutic decisions in rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic, immune-mediated inflammatory disease that has transitioned from a debilitating disease to a chronic, controllable disease. This has been possible due to the introduction of new treatment strategies like "treat-to-target," in which the clinician treats the patient aggressively enough to reach low disease activity or remission, and the introduction of new therapeutic agents, such as biological therapies, which can lead to the prevention of damage by early diagnosis and initiation of treatment. Attention is now being directed toward identifying the optimal treatment for each patient, one that will be the most efficient and have the least number of side effects. Much work has been done to find serologic and synovial biomarkers of response to various RA treatments. Proteomics, genomics and, in the past few years, metabolomics, have all been used in the quest of identifying these biomarkers. Blood-based liquid biopsies provide a minimally invasive alternative to synovial biopsies to identify cellular and molecular signatures that can be used to longitudinally monitor response and allow for personalized medicine approach. Liquid biopsies are comprised of cell-free DNA, immune circulating cells, and extracellular vesicles, and are being increasingly and successfully used in the field of oncology for diagnosis, progression, prognosis, and prediction of response to treatment. Recently, researchers have also begun investigating the usefulness of liquid biopsies in the field of rheumatology; in this review, we will focus on the potential of liquid biopsy blood samples as biomarkers of response to treatment in patients with RA.