Tartrate-Resistant Acid Phosphatase Isoenzyme in the Reticulum Cells of Leukemic Reticuloendotheliosis

Abstract

Acid phosphatase activity in the reticulum cells of leukemic reticuloendotheliosis is quantitatively and qualitatively different from that in the lymphosarcoma cells of lymphosarcoma and in lymphocytes of chronic lymphocytic leukemia. Enzyme activity in the reticulum cells is strong and tartrate resistant, whereas that in the lymphoid cells of the other two diseases is very weak and is inhibited by tartrate. A combined cytochemical and electrophoretic study indicates that this tartrate-resistant enzyme activity represents isoenzyme 5. It is present almost exclusively in the reticulum cells and not in other hemic cells in leukemic reticuloendotheliosis. It is not present in the lymphoid cells in lymphosarcoma or chronic lymphocytic leukemia. It may be used as the marker enzyme to diagnose leukemic reticuloendotheliosis and to trace the origin of the "reticulum cells" ("hairy cells") in the reticuloendothelial system.