Plasma levels of human granulocytic elastase alpha 1-proteinase inhibitor complex (E-alpha 1-PI) in leukemia.

There is evidence that polymorphonuclear granulocytes release neutral proteinases such as elastase (E) and cathepsin G in the course of acute leukemia. These proteinases may inactivate clotting factors by unspecific degradation before they are eliminated via complex formation with endogenous inhibitors, e.g. the alpha 1-proteinase inhibitor (alpha 1-PI). In this study it was attempted to correlate plasma levels of the E-alpha 1-PI complex with factor XIII and antithrombin III in acute leukemia. Using a newly developed, sensitive enzyme-linked immunoassay the concentration of E-alpha 1-PI in patients with various types of leukemia, malignant lymphoma or multiple myeloma was determined. Only patients with acute myelocytic or promyelocytic leukemia (AML, APL) and chronic myelocytic leukemia with and without blastic transformation (CML) showed moderate to high levels of E-alpha 1-PI (2- to 20-fold of normal). However, coagulation factor concentration observed in the different types of leukemia seemed to be independent of elastase liberation. Most of the AML-patients with elevated E-alpha 1-PI levels showed peroxidase positive blood cell smears.