Estudo da proteína survivina no processo inflamatório e na sobrevida de neutrófilos

Abstract

Acute Inflammation is the fundamental mechanism by which multicellular organisms deal with injury caused either by infectious or non-infectious insults. During the acute inflammation, circulating neutrophils are the first leukocytes to reach the inflamed site, and have been regarded as first line of host defense against noxious stimulus. In general, after neutrophils play their role in inflammatory site, they are removed from tissues by apoptosis and subsenquent phagocytosis by macrophage. Thus, inflammation must be a highly controlled process in order to culminate in its resolution and return of tissue homeostasis. Uncontrolled or unresolved inflammation can be asssociated to increased neutrophil survival and prolonged inflammatory response culminating in chronic diseases. The contact of neutrophils with resident tissue cells and inflammatory mediators results in the activation of neutrophils and increased lifespan of these cells. This process is mediated by anti-apoptotic molecules and regulators of pro-apoptotic molecules. Survivin is a component of the Apoptosis Inhibitory Proteins family (IAPs) family and has its role extensively studied in cells with high proliferative potential and viability, including cancer cells. Recently, some studies have demonstrated their participation in the development of autoimmune diseases, but their expression and function in cells of the immune system and maintenance of inflammatory response is unknown. Thus, the objective of this work was to study the expression and function of survivin in the acute inflammatory process induced by LPS and to neutrophil survival.