CYTOCHEMICAL DEMONSTRATION OF β-GLUCURONIDASE ACTIVITY IN BLOOD AND BONE MARROW CELLS

A method for the cytochemical demonstration of β-glucuronidase activity in blood and bone marrow is described using naphthol AS-BI-β-d-glucosiduronic acid as substrate and hexazotized pararosanilin as coupling reagent. β-Glucuronidase was found to be present in most of the cells of blood and marrow. The reaction was strongly positive in macrophages, monocytes, plasma cells and some of the lymphocytes. It was moderately positive in granulocytes and thrombocytes and weakly positive in cells of the erythroid series. β-Glucuronidase is known to be a lysosomal enzyme, but certain discrepancies exist between the content of this enzyme and the number of lysosomal structures as seen electron microscopically. It appears that not all of the lysosomes contain β-glucuronidase and that sites of β-glucuronidase other than lysosomal exist in certain cell lines, i.e., the lymphocytes and the plasma cells. For this reason, it is suggested that cytochemical investigations of lysosomes should always include the simultaneous demonstration of different lysosomal hydrolases.