Prospective Studies on the Risk of Rheumatoid Arthritis: The European Risk RA Registry

The peculiar features, diversity and impact of citrulline-reactive autoantibodies

Since entering the stage 25 years ago as a highly specific serological biomarker for rheumatoid arthritis, anti-citrullinated protein antibodies (ACPAs) have been a topic of extensive research. This hallmark B cell response arises years before disease onset, displays interpatient autoantigen variability, and is associated with poor clinical outcomes. Technological and scientific advances have revealed broad clonal diversity and intriguing features including high levels of somatic hypermutation, variable-domain N-linked glycosylation, hapten-like peptide interactions, and clone-specific multireactivity to citrullinated, carbamylated and acetylated epitopes. ACPAs have been found in different isotypes and subclasses, in both circulation and tissue, and are secreted by both plasmablasts and long-lived plasma cells. Notably, although some disease-promoting features have been reported, results now demonstrate that certain monoclonal ACPAs therapeutically block arthritis and inflammation in mouse models. A wealth of functional studies using patient-derived polyclonal and monoclonal antibodies have provided evidence for pathogenic and protective effects of ACPAs in the context of arthritis. To understand the roles of ACPAs, one needs to consider their immunological properties by incorporating different facets such as rheumatoid arthritis B cell biology, environmental triggers and chronic antigen exposure. The emerging picture points to a complex role of citrulline-reactive autoantibodies, in which the diversity and dynamics of antibody clones could determine clinical progression and manifestations.

In silico and in vitro studies for the identification of small molecular inhibitors from Euphorbia hirta Linn for rheumatoid arthritis: targeting TNF-α-mediated inflammation

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that is now potentially lethal and has a significant detrimental influence on people's daily lives by affecting bone joints. Inflammation plays a vital role in this type of autoimmune disorder. In rheumatoid arthritis, long-term production of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1) stimulates the immune system against cells in bone joints and helps to develop the pathogenesis of rheumatoid arthritis. So, while treating rheumatoid arthritis, we need to block these kinds of mechanisms. We employed soxhlet extraction, thin-layer chromatography (TLC), and gas chromatography-mass spectroscopy (GC-MS) to analyze the phytocompound information in E. hirta leaves. Furthermore, our research included in vitro investigations using Western blotting and mRNA expression analysis (TNF-α, IL-1β, IL-6) to affirm the anti-inflammatory effectiveness of our extract. For identifying the lead-like molecules, virtual screening and molecular dynamics simulations were used. TLC results confirmed the presence of phytocompounds in E. hirta crude through spots. The structure elucidation of the phytocompounds was confirmed by the GC-MS chromatogram. The in vitro outcomes collectively underscore the inhibitory influence of E. hirta on cell proliferation and its capacity to attenuate the expression of TNF- α within THP-1 cells. The results of in silico methodologies confirmed six lead-like molecules. We could conclude that phytocompounds from ethanol leaf crude have effective lead-like molecules against the TNF-α.

Prevention of rheumatoid arthritis: A systematic literature review of preventive strategies in at-risk individuals

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by symmetrical peripheral polyarthritis in the hands and/or feet, leading to long-term disability if not treated effectively. RA is preceded by a preclinical phase, in which genetically predisposed individuals accumulate environmental risk factors, and during which autoimmunity develops, followed by the emergence of non-specific signs and symptoms before arthritis becomes manifest. Early treatment in at-risk individuals - i.e. before the disease is fully established - has the theoretical potential to delay or prevent disease onset, with a positive impact on both patients' life and society.

OBJECTIVES

We aimed to understand the feasibility of preventive treatment in at-risk individuals, taking into account recently performed studies and ongoing clinical trials, as well as patient perspectives.

METHODS

We performed a systematic literature review (SLR) on Medline and Embase, searching articles published between 2010 and 2021 with the following key-words: "Rheumatoid arthritis", "arthralgia", "pre-treatment" or "prevent".

RESULTS

Our SLR identified a total of 1821 articles. Articles were independently screened by two researchers. A total of 14 articles were included after screening, and an additional 8 reports were manually included. We identified ten relevant clinical trials performed in at-risk individuals, or in individuals with undifferentiated inflammatory arthritis. Although no treatment was shown to prevent RA onset, early treatment with rituximab and abatacept delayed onset of full-blown RA, and both conventional and biological disease-modifying anti-rheumatic drugs (DMARDs) decreased disease-related physical limitations and increased DAS28-defined remission, at least temporarily.

CONCLUSIONS

This SLR demonstrates that early treatment of at-risk individuals may be effective in delaying RA onset, thereby decreasing disease-related limitations in individuals in the pre-clinical phase of RA. Whether this may ultimately lead to prevention of RA remains to be determined.