HISTOCHEMISTRY OF THE CENTRIOLES AND CENTROSOMES OF THE LEUKEMIC CELLS FROM HUMAN MYELOBLASTIC LEUKEMIA

Recent studies have provided considerable information concerning the morphology and fine structure of the centrioles and centrosome (4, 6, 12). Although little is known of the chemical composition of these structures, histochemical evidence indicates that they are composed of basic protein, ribonucleoprotein, and glycoprotein (7, 17); the centrosome or astrosome accumulates sulfhydryls during mitosis (13). It is the purpose of this study to examine the histochemical composition of the centrioles and centrosome observed in human leukemic myeloblasts during interphase. Leukemic myeloblasts observed from two patients with acute myeloblastic leukemia exhibited exceptionally prominent centrosomes and readily identifiable centrioles. Usually, the positive recognition of centrioles either in normal or leukemic cells of the blood and bone marrow is difficult or impossible and cytoplasmic granules or mito-chondria residing in close proximity to the cen-trosome may be mistaken for centrioles. Vital and supravital (neutral red and Janus green) films were examined with brightfield and phase contrast microscopy. The following histo-chemical procedures were carried out on blood films after appropriate fixation: Wright's stain and ribonuclease digestion for pentosenucleoprotein (2); Fast green FCF at pH 2 for basic protein (16); Weiss, Tsou, and Seligman's method for protein-bound amino groups (18); Landing and Hall's method for histidine (14); Glenner's post coupled benzilidine method for indole derivatives (trypto-phane) (10); Barrnett and Seligman's method for protein-bound sulfhydryl groups (3, 5), the periodic acid-Schiff method for glycoproteins and salivary digestion for glycogen (2), Sudan black B for lipids (2), naphthol AS-MX phosphate method for alkaline phosphatase (8), naphthol AS-D chloro-acetate method for esterase (15), Burstone's method for alanyl aminopeptidase (1, 9) and Graham's method for peroxidase activity (11). Blood samples obtained from one patient were fixed in buffered osmium tetroxide, embedded in methacrylate, and examined under the electron microscope. Phase contrast microscopy revealed the cen-trosome to be optically less dense than the surrounding cytoplasm (Figs. 1, 3). Spherical mito-chondria tended to be localized near the well circumscribed cytocentrum. In the living leukemic interphase cells, the centrioles, although slightly smaller than the mitochondria, exhibited similar optical density (Figs. 1, 3). Centrioles were observed to move slowly within the centrosomal zone. The centrioles and centrosome did not stain with either neutral red or Janus green in supravital films. Electron microscopy confirmed the presence of centrioles in the clear zone or centrosome located within the nuclear hof (Fig. 2). The cen-trosome tended to be surrounded by Golgi membranes and vesicles, contained few ribosomes, …