Abstract
About 100 years ago, Eli Metchnikoff had already expressed the importance of phagocytic cells in host defense. Today everyone admits that neutrophils are playing the most important role. Neutrophils migrate near the invading microorganisms, ingest them, kill them and digest them. Number and quality of neutrophils must be adequate in order to fulfill its function. Abnormal neutrophil function can be thought of as intrinsic cell defects, defects due to mediators acting on the cell and abnormalities related to shifts in populations of normal cells. The recent reviews of abnormal processes of neutrophil maturation, margination, chemotaxis, phagocytosis and killing will be explained in this capter.
