Cationic protein-bearing granules of polymorphonuclear leukocytes: separation from enzyme-rich granules.

The cationic, antibacterial proteins of polymorphonuclear leukocytes are associated with a unique subcellular particle that is separable through zonal density gradient centrifugation from acid phosphatase-containing particles as well as from particles that contain alkaline phosphatase and lysozyme. Normal macrophages, macrophages stimulated by bacillus Calmette-Guérin, and liver cells lack this particle and the associated group of cationic proteins. Particles physically and biochemically similar to slower sedimenting enzyme-rich particles of polymorphonuclear leukocytes are shared by all the tlhree cell types.