Platelet-leukocyte deregulated interactions foster sterile inflammation and tissue damage in immune-mediated vessel diseases

Platelets and leukocytes co-localize and interact at sites of vessel injury, haemorrhage, thrombosis and inflammation. Recent studies have highlighted the role of local cues in the interaction between the two cell populations, including the exposure of anionic phospholipids and the release of Damage Associated Molecular Patterns (DAMPs) by activated platelets, the release of the prototypical tissue pentraxin PTX3 by neutrophils, as well as the generation of polarized clusters of neutrophil beta(2) integrins. In turn, the reciprocal activatory cross-talk between platelets and leukocytes contributes to the generation of thrombo-inflammatory lesions and of vascular injury. Here we will discuss the implications of these results for the pathogenesis and the clinical features of self-sustaining immune-mediated vessel diseases. (C) 2011 Elsevier Ltd. All rights reserved.