INTERLEUKIN-1 RECEPTOR ANTAGONIST (IL1RA) IN ACUTE-LEUKEMIA - IL1RA IS BOTH SECRETED SPONTANEOUSLY BY MYELOGENOUS LEUKEMIA BLASTS AND IS A PART OF THE ACUTE-PHASE REACTION IN PATIENTS WITH CHEMOTHERAPY-INDUCEDLEUKOPENIA

Blast cells derived from peripheral blood of patients with acute myelo genous leukaemia (AML) were cultured in vitro and interleukin 1 recept or antagonist (IL1RA) concentrations determined in culture supernatant s. AML blasts derived from patients classified as AML-M4 and AML-MS su btype showed an increased release of IL1RA. IL1 alpha and IL1 beta cau sed a similar increase in AML blast release of IL1RA, and addition of anti-IL1 antibodies decreased IL1RA release. IL1RA release from AML bl asts was also increased by stem cell factor, tumour necrosis factor al pha (TNF alpha), granulocyte-macrophage colony-stimulating factor and macrophage colony-stimulating factor, whereas interleukin 3, interleuk in 6, leukaemia inhibitory factor and granulocyte colony-stimulating f actor did not significantly alter IL1RA release. When investigating IL 1RA serum levels, serum concentrations were decreased in acute leukaem ia patients with chemotherapy-induced cytopenia compared with healthy controls. Serum levels of both IL1RA as well as IL1 beta and soluble T NF alpha receptors increased when the leucopenic patients developed co mplicating bacterial infections.