Interferon-α potentiates priming-dependent FMLP-induced neutrophil superoxide generation in a patient with chronic myeloid leukemia

13 year old girl diagnosed as having chronic myeloid leukemia (CML) was treated with interferon-α (IFN-α) alone and 4 months later hematological remission was obtained. In the course of the IFN-α treatment there was neither infectious sign nor side effects. In this study we have examined the effect of IFN-α on superoxide O₂^? generation by polymorphonuclear neutrophils (PMN). The PMN of the patient generated less O₂^? than PMN from normal controls. When patient PMN were cultured in the presence of 1000 U/mL IFN-α, enhancement of the formyl-methionyl-leucyl-phenylalanine induced O₂^?generation following priming with tissue necrosis factor-α was observed. Over the course of the IFN-α therapy, such O₂^? generation was gradually restored. It is suggested that CML PMN are in the resting condition in terms of their ability to generate O₂^? and that IFN-α is effective in inducing O₂^? generation by CML PMN.