Platelets: active players in the pathogenesis of arthritis and SLE
Nature Reviews Rheumatology , 08/09/2012
Boilard E et al. – The findings point to a distinct role for platelets in autoimmunity and support the possibility that platelets are an attractive target in rheumatic disease.
- Studies have shown that platelets can have unexpected roles in rheumatic diseases. In patients with rheumatoid arthritis (RA), IL-1-containing platelet-derived vesicles called microparticles are abundant in arthritic joint fluid.
- These microparticles can elicit production of inflammatory mediators from resident synovial fibroblasts, which have an integral role in the development of arthritis.
- Platelets also serve as a source of prostaglandins that contribute to synovial inflammation.
- Furthermore, serotonin released by platelets helps drive the persistent vascular permeability that characterizes the microvasculature of the inflamed synovium, an unexpected function for a cell that more typically serves as a guardian of vascular integrity.
- Beyond RA, platelet activation has been observed in systemic lupus erythematosus, mediated at least in part through the interaction of circulating immune complexes with platelet Fc receptors and by promotion of interferon release from plasmacytoid dendritic cells.