HISTOCHEMICAL DEMONSTRATION OF SULFATED MUCOSUBSTANCES AND CATIONIC PROTEINS IN HUMAN GRANULOCYTES AND PLATELETS

Histochemical staining methods visualize sulfated mucosubstance in numerous small granules of early neutrophil leukocytes in appropriately processed human bone marrow smears. These reactive granules presumably constitute the counterpart in human neutrophils of the mucosaccharide-rich primary granules in rabbit heterophils. Neutrophils at a late developmental stage in human marrow or buffy coat smears reveal few or no granules with such reactivity. Strong staining for sulfated mucosubstance is readily demonstrable in numerous large cytoplasmic granules in human eosinophils. This reactivity diminishes but does not disappear during maturation of the eosinophil and its single population of cytoplasmic granules. Granules of human basophils at all developmental stages stain for sulfated mucosubstance. Platelets in human buffy coat smears reveal evidence for sulfated mucosaccharide. The mucosaccharide-containing granules of the three myeloid series also disclose acidophilia at high pH indicative of the presence of strongly cationic proteins.