title: Ultrastructural localization of acid alpha-naphthylacetate esterase in human normal and neoplastic lymphocytic and monocytic cells and in hairy cells.
abstract: The ultrastructural localization of acid alpha-naphthylacetate esterase (ANAE) activity was studied in normal and neoplastic human monocytic and lymphocytic cells including hairy cells. Normal monocytes and malignant monocytic cells from cases of AML-M4 and -M5 (FAB-classification) displayed fundamentally the same ANAE staining pattern with reaction products localized to the external surface of the plasma membrane and to small vesicles close to this membrane, more rarely to larger intracytoplasmic vesicles containing endocytosed material or cellular debris. The enzyme activity of the neoplastic cells increased with morphological differentiation. Certain normal blood lymphocytes and T cell-derived CLL cells showed the reaction product associated with paranuclearly located clusters of vesicular structures, extending from the membranes into the adjacent cytoplasm. Gall bodies were often found in the vicinity and were invariably positive for ANAE. Now and then, plasma membrane activity was present, but never as pronounced as in monocytes. Hairy cells demonstrated a pattern of reaction very similar to that of monocytic cells, whereas B cell-derived CLL cells and lymphoblasts of T- and common type ALL were generally non-reactive.
mesh_terms: D002265:Carboxylic Ester Hydrolases / Q000097:blood*; D006801:Humans; D007943:Leukemia, Hairy Cell / Q000201:enzymology*; D008214:Lymphocytes / Q000201:enzymology / Q000648:ultrastructure*; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000201:enzymology / Q000648:ultrastructure*; D009283:Naphthol AS D Esterase / Q000097:blood*; D012397:Rosette Formation
chemical_list: D009283:Naphthol AS D Esterase; D002265:Carboxylic Ester Hydrolases