NEUTROPHIL 5-NUCLEOTIDASE REACTION IN CHRONIC MYELOGENOUS LEUKEMIA, MYELOFIBROSIS WITH MYELOID METAPLASIA, AND POLYCYTHEMIA-VERA

A readable and reproducible 5-nucleotidase (5N) cytochemical reaction was developed for blood smear preparation, after modification of the t echnique of Wachstein and Meisel [37]. The reaction was applied to nor mal polymorphonuclear neutrophils (NPN) and to neutrophils from patien ts with chronic myelogenous leukemia (CML), myelofibrosis with myeloid metaplasia (MMM), and polycythemia vera (PV). The following observati ons were made: (a) 5N was present in NPN, with a mean score of 83.2+/- 15.7. (b) In patients with MMM and PV an increased 5N score was observ ed (mean score 111+/-63.8 and 178.3+/-83.3, respectively). (c) In CML the mean score was 4.9+/-2.2. (c) A statistical comparison of neutroph il 5-nucleotidase (N5N) between CML and MMM and PV patients demonstrat ed a highly significant difference (p<0.0001). In the present study, w e showed that the N5N activity parallels that of NAP in chronic myelop roliferative disorders such as CML, MMM, and PV. It appears that, apar t from the already known activity of NAP in myeloproliferative disorde rs, other enzymes (e.g., N5N) can present a similar behavior with incr eased or decreased activity.