PECAM-1 functions as a negative regulator of laminin-induced platelet activation.

摘要: Summary. Background: Interaction of resting platelets with exposed components the subendothelial matrix is an important early activating event that takes place at sites vascular injury. Platelet responses to collagen are mediated by integrin α2β1 and glycoprotein (GP)VI–Fc receptor (FcR) γ-chain complex, whereas platelet activation laminin related integrin, α6β1, similarly requires signaling through GPVI–FcR γ-chain. Objective: Because cell adhesion PECAM-1 has previously been shown dampen collagen-induced activation, we sought determine whether might regulate laminin. Methods/Results: We found became tyrosine phosphorylated on its cytoplasmic immunoreceptor tyrosine-based inhibitory motifs following either human or murine immobilized Whereas presence absence had no effect rate extent spreading laminin, inhibited laminin-induced phosphorylation (ITAMs) downstream effector, Syk kinase, suppressed granule secretion. Conclusions: Taken together, these data consistent previous findings in other blood cells functions modulating ITAM-mediated pathways amplify cellular activation.