The Role of Interleukin-8 in Patients with Hematologic Diseases

We measured the plasma Interleukin-8 (IL-8) concentration in 240 patients with hematological diseases to investigate the role of IL-8 in hematologic disease. Significantly higher concentrations of IL-8 were observed in some patients with acute myelogenous leukemia (AML), acute lymphoid leukemia, and chronic myelogenous leukemia than in healthy control subjects. We found no correlation between the plasma IL-8 concentration and the number of white blood cells, neutrophils, or monocytes, and the serum C-reactive protein concen-tration. In one patient with acute monocytic leukemia (M5), the high plasma concentrations of IL-8 before treatment fell to control levels after chemotherapy along with a decrease in the number of leukemic monocytes. A positive correla-tion was observed between plasma IL-8 and IL-6, but not between the concen-trations of other cytokines. High concentrations of IL-8 were detected in the supernatant of primary cultures of leukemia cells collected from 10 patients with AML. The reverse transcriptase-polymerase chain reaction showed that these cells expressed IL-8 mRNA. Leukemic cells might therefore be the main source of IL-8 in vivo under some circumstances. IL-8 might participate in the funda-mental disease process of AML, in addition to its role in inflammation.