Choline Esterase of Blood Cells and Plasma in Blood Dyscrasias, with Special Reference to Pernicious Anemia.

Interest in the distribution of choline esterase activity between the cells and plasma dates back a dozen years or more, but relatively little investigation has been carried out. In 1928 Galehr and Plattner (1), using a biological assay method, found that there was more choline esterase activity in human blood cells than in serum, and their finding was confirmed by Matthes (2) in 1930. The esterase activity of whole blood, hemolyzed blood and serum of man and other species was studied by Ammon and Voss (3). Human blood, whole or hemolyzed, was found to be more active than serum, and dog blood less active than serum. The distribution of esterase activity between blood cells and serum of defibrinated blood was studied by Stedman and Stedman (4) in normal persons and in a number of species of animals, and by Stedman and Russell (5) in twelve myasthenia gravis patients and a group of muscular, neuromuscular and psychopathic cases. They found marked species differences, both as to choline esterase activity and as to distribution of activity between plasma and cells. In the normal human they found that the cells have consistently more activity than the plasma. Their myasthenia gravis patients showed a decrease in plasma esterase and an esterase value for cells approximating the normal values. In the myopathic and psychopathic group they found a general lowering of plasma esterase and a variety of disturbances of the esterase distribution. That the activity of the formed elements of the blood resides chiefly in the red cells is generally accepted. Ginsberg et al. (6) found that washed pus cells showed no esterase activity. In April, 1940, Alles and Hawes reported qualitative differences between the choline esterase of blood cells and of plasma in their behavior toward different substrates and toward different concentrations of the same substrate. Further reference to this work will be made in the discussion. Information concerning the esterase activity in anemias is very meager. Antopol et al. (7) list a case of secondary anemia and one of acute hemolytic anemia in a series of cases of jaundice and liver disease in which there was a general lowering of serum esterase. Milhorat (8) reports values for a long list of varied clinical conditions. Among them are a case of primary anemia and one of acute myeloid leukemia. The degree of anemia is not stated for either case. The primary anemia showed a normal esterase activity in the serum; the leukemia, a markedly lowered value. He states that no correlation was found with red cell count or hemoglobin in this series. As a tentative investigation, preliminary to the present study, determinations were made on the esterase activity of two dogs in the laboratory of the Pathology Department, through the courtesy of Dr. Sidney Madden and Mr. Albert Rowe. These dogs were made anemic by repeated phlebotomy. In the normal period the dogs were found to have an appreciably higher esterase activity in the plasma than in the whole blood. This is in accord with the results of Ammon and Voss (3) and with unpublished results of Dr. Fenn in this laboratory. As the hematocrit fell, a lowering of the plasma esterase was observed. A slight fall in the whole blood esterase occurred, but the calculated value for blood cells showed a marked rise. On this lead it was decided to investigate the esterase activity of the cells and plasma of patients with anemias of various etiologies.