Micro-RNA content of circulating extracellular vesicles in early rheumatoid arthritis as biomarkers and mediators of methotrexate efficacy

Elucidating the molecular mechanisms of CCR5-containing extracellular vesicles in vitro and in a rat model of experimental Rheumatoid arthritis

Extracellular vesicles from Rheumatoid arthritis (RA) derived synovial fibroblasts (EVsRASF) have been implicated in the pathogenesis of RA, acting as mediators of cell-to-cell communication. This study aimed to elucidate the role of the chemokine receptor CCR5 and EVs positive for CCR5 (EVsRASF) in RA, focusing on their impact on cartilage destruction and bone erosion in a rat model of Adjuvant-induced arthritis (AIA). In vivo experiments were conducted using AIA rats, treated with either EVsRASF, EVsRASF without CCR5 (EVsRASF-CCR5), or EVsM which encapsulated the CCR5 antagonist Maraviroc. The results demonstrated that EVsRASF-CCR5 reversed the catabolic effect of EVsRASF on hRA-CHs. EVsRASF accelerated cartilage destruction and bone erosion in the AIA rats, as evidenced by increased arthritis scores, joint damage, and NF-κB activation. In contrast, EVsRASF-CCR5 and EVsM treatment mitigated these effects, suggesting a detrimental role of CCR5 in EVsRASF-mediated RA pathogenesis. These findings highlight the critical role of CCR5 in mediating the pro-inflammatory and destructive effects of EVsRASF in RA, suggesting that targeting CCR5 may represent a novel therapeutic strategy for RA management. In conclusion, this study provides valuable insights into one of the molecular mechanisms underlying RA pathogenesis, emphasizing the importance of EVsRASF and CCR5 in mediating synovial inflammation and joint destruction. The results underscore the potential of CCR5 as a therapeutic target, opening avenues for the development of targeted interventions in RA treatment with synovial fibroblast derived EVs serving as a convenient, stabilizing vehicle for delivering Maraviroc into the RA affected joint tissues.

Role of microRNAs in Immune Regulation with Translational and Clinical Applications

MicroRNAs (miRNAs) are 19-23 nucleotide long, evolutionarily conserved noncoding RNA molecules that regulate gene expression at the post-transcriptional level. In this review, involvement of miRNAs is summarized in the differentiation and function of immune cells, in anti-infective immune responses, immunodeficiencies and autoimmune diseases. Roles of miRNAs in anticancer immunity and in the transplantation of solid organs and hematopoietic stem cells are also discussed. Major focus is put on the translational clinical applications of miRNAs, including the establishment of noninvasive biomarkers for differential diagnosis and prediction of prognosis. Patient selection and response prediction to biological therapy is one of the most promising fields of application. Replacement or inhibition of miRNAs has enormous therapeutic potential, with constantly expanding possibilities. Although important challenges still await solutions, evaluation of miRNA fingerprints may contribute to an increasingly personalized management of immune dysregulation with a remarkable reduction in toxicity and treatment side effects. More detailed knowledge of the molecular effects of physical exercise and nutrition on the immune system may facilitate self-tailored lifestyle recommendations and advances in prevention.

The Role of Extracellular Vesicles in the Pathogenesis and Treatment of Rheumatoid Arthritis and Osteoarthritis

Cells can communicate with each other through extracellular vesicles (EVs), which are membrane-bound structures that transport proteins, lipids and nucleic acids. These structures have been found to mediate cellular differentiation and proliferation apoptosis, as well as inflammatory responses and senescence, among others. The cargo of these vesicles may include immunomodulatory molecules, which can then contribute to the pathogenesis of various diseases. By contrast, EVs secreted by mesenchymal stem cells (MSCs) have shown important immunosuppressive and regenerative properties. Moreover, EVs can be modified and used as drug carriers to precisely deliver therapeutic agents. In this review, we aim to summarize the current evidence on the roles of EVs in the progression and treatment of rheumatoid arthritis (RA) and osteoarthritis (OA), which are important and prevalent joint diseases with a significant global burden.