Chapter 7 - NEUTROPHIL LEUKOCYTES

Abstract

This chapter discusses the commonest type of blood phagocyte, the neutrophil. This cell has a variety of names, most of which reflect some prominent feature of its structure or function and none of which is, in fact, entirely suitable. Polymorphonuclear leukocyte or granulocyte are not sufficiently specific designations, as they apply equally well to neutrophils, eosinophils, and basophils. Similarly lacking in precision is the name microphage, a term used by Metchnikoff for the polymorphonuclear phagocytic cell in blood or tissues to distinguish it from its larger mononuclear relative, the macrophage. Neutrophilic leukocyte or neutrophil would be entirely satisfactory terms. The appearance of neutrophils after fixation and staining with mixed dyes of the Romanovsky type is well known. The unusual nuclear shape of neutrophils is one of the most striking features of these cells. One of the most distinguishing features of neutrophils is the abundance of cytoplasmic granules, a feature giving rise to the alternate name, granulocyte. Neutrophil granules contain at least two classes of nonenzymatic substances, namely, mucopolysaccharides and cationic proteins.