Evidence for keratinocyte-derived microvesicle particles as carriers for the potent lipid mediator platelet-activating factor as effectors for systemic effects associated with many environmental stressors.

Skin is constantly exposed to environmental and iatrogenic stressors, and its response varies depending on the type of stress. Responses from these stressors include acute local and systemic multiorgan inflammation and delayed immunosuppression. Unfortunately, the mechanisms behind these effects regarding effectors remain unclear. In this review, we provide evidence for a pathway in which the damaged skin keratinocyte responds through formation of effector platelet-activating factor within microvesicle particles. This paper highlights the therapeutic potential of blocking this process through pharmacologic inhibition of the enzyme acid sphingomyelinase needed for microvesicle particle biogenesis.