Serum and Plasma Myeloperoxidase, Elastase and Lactoferrin Content in Acute Myeloid Leukaemia

Abstract

Myeloperoxidase (MPO) and elastase, restricted to azurophil granules of neutrophils, and lactoferrin, restricted to specific granules of neutrophils, were determined in plasma and serum from patients with acute myeloid leukemia (AML). Highly sensitive radioimmuno assays were developed for detection of these proteins. Serum MPO was increased in 12 of 35 and decreased in 2 of 35 patients without correlation to WBC [white blood count] or neutrophil counts; these levels may reflect an abnormal production by leukemic blasts or ineffective granulopoiesis in the bone marrow. Serum elastase was increased in 6 of 22 patients. Serum lactoferrin was decreased in 12 of 25 patients without correlation to neutrophil counts, probably reflecting abnormal production. Serum elastase and MPO showed a covariation in chronic myeloid leukemia but not in AML; the latter finding may indicate that the synthesis of these 2 proteins is not synchronized in AML-cells. Sequential studies of patients with AML demonstrated fluctuations of serum MPO and lactoferrin during remission probably because of chemotherapeutic pertubation. Although a limited number of patients were studied, serum lactoferrin may be of help for prediction of relapse in AML.