Neutrophil‐Derived Microparticles as Novel Effectors in Joint Disease

• DOI: 10.1096/fasebj.27.1_supplement.137.6
• Publication Date: 2021-06-16T10:25:54Z
• Authors: Sarah Emily Headland; Francesco Dell'Accio; Mauro Perretti
• Keywords: 0301 basic medicine; 03 medical and health sciences; 3. Good health

Microparticles (MPs) are small membrane‐bound vesicles released by cells upon activation. Numerous reports have detected MPs in the synovial fluid of Rheumatoid Arthritis (RA) patients. Whilst Tcell‐ derived MPs activate synoviocytes, recent reports have shed light on the possible anti‐inflammatory phenotype of neutrophilderived MPs, challenging the linear model of inflammation. The aim of the study is to unveil the role of neutrophil‐derived MPs in RA, particularly in the context of cartilage biology. Microparticles generated from human neutrophils were characterised by flow cytometry and tested for chondroprotective efficacy in a C28/I2 micromass model of cartilage turnover. These experiments revealed protective actions. Investigation in whole cartilage explants indicated chondroprotection (demonstrated by safranin O staining) as studied over a seven‐day period. Microparticle entry into cartilage was also investigated using confocal microscopy. In conclusion, we report novel biological functions of neutrophil MPs with potential relevance to cartilage biology and arthritis.Supported by Oliver Bird Studentship Scheme QMUL/KCL