Authors: Sarah E. Headland, Hefin R. Jones, Lucy V. Norling, Andrew Kim, Patricia R. Souza, Elisa Corsiero, Cristiane D. Gil, Alessandra Nerviani, Francesco Dell’Accio, Costantino Pitzalis, Sonia M. Oliani, Lily Y. Jan and Mauro Perretti
Summary:
Neutrophils play an active role in protecting cartilage from damage by dispatching microvesicles (MVs) to do their bidding in this tissue they otherwise can’t access. Headland and colleagues found MVs present in the synovial fluid of patients with rheumatoid arthritis—an autoimmune disease that degrades cartilage in the joints. Cartilage is normally thought of as impenetrable to cells, so neutrophils send MVs, which easily enter the tissue and prevent damage induced by disease through a complex mechanism that involves the proresolving protein annexin A1 and its receptor. In two different mouse models of rheumatoid arthritis, MVs delivered locally entered the cartilage, prevented the loss of proteoglycans, and maintained cartilage integrity. This study suggests that immune cells can provide protection against tissue degradation in inflammatory arthritis and that the MVs may be manipulated to deliver therapeutics to diseased joints.
Source:
Abstract (Science Translational Medicine; Vol. 7, Issue 315, 315ra90 (11/25/15))