The role of platelet-activating factor (PAF) in interstitial pulmonary disease.

Platelet-activating factor (PAF) is a biolipid of crucial importance in the inflammatory response. In the first part of this work we review the basic biochemical characteristics of PAF. Also, the production and degradation of PAF by inflammatory cells is detailed in depth, with a description of enzymes linked to these processes. Subsequently, we examine the main characteristics of the generation of PAF by pulmonary cells, with emphasis on its production by alveolar macrophages. We then discuss in depth the effects of this biolipid on the inflammatory cells present in interstitial disease. In this part of the review we describe the direct effect of PAF on polymorphonuclear leukocytes (neutrophils and eosinophils), mononuclear phagocyte system cells, lymphocytes and endothelial cells. We then examine the indirect effect of PAF on inflammatory cells (mainly due to an interaction with neuropeptides). Finally, we discuss the data on the role of PAF in diffuse interstitial pulmonary disease (both human and experimental).