ULTRASTRUCTURE AND CYTOCHEMICAL CHARACTERISTICS OF LEUKOCYTE INFECTEDWITH HEPATOZOON CANIS

We have observed the ultrastructure of a canine leukocyte infected wit h Hepatozoon canis by transmission electron microscope. The infected l eukocytes contained many small Vesicles and a few typical granules in the cytoplasm. They also contained a few rough surfaced endoplasmic re ticula, mitochondria and a segmented nucleus with condensed chromatin. Cytochemical analysis indicated that the infected leukocytes with H. canis contained little alkaline phosphatase, peroxidase, naphthol AS-D chloroacetate esterase or alpha naphthol acetate esterase. These resu lts suggested that the infected leukocytes were neutrophils or monocyt es which lost their typical characteristics.