Effects of anti- TNF- α agents on circulating endothelial-derived and platelet-derived microparticles in psoriasis.

Psoriasis involves TNF- α secretion leading to release of microparticles into the bloodstream. We investigated the effect of TNF blockers on microparticles levels before and after treatment in patients (twenty treated by anti- TNF- α agents and 6 by methotrexate) with severe psoriasis. Plasmatic microparticles were labelled using fluorescent monoclonal antibodies and were analysed using cytometry. Three months later, 70% of patients treated with anti- TNF- α agents achieved a reduction in PASI score of at least 75%. The clinical improvement in patients treated with anti- TNF- α agents was associated with a significant reduction of the mean number of platelet microparticles (2837/ μl vs 1849/ μl, P = 0.02) and of endothelial microparticles (64/ μl vs 22/ μl, P = 0.001). Microparticles are significantly decreased in psoriatic patients successfully treated by anti- TNF- α. Microparticles levels as circulating endothelial cells represent signs of endothelial dysfunction and are elevated in psoriasis. Then, TNF blockade may be effective to reduce cardiovascular risk through the reduction of circulating microparticles. [ABSTRACT FROM AUTHOR]