High expression of neutrophil elastase predicts improved survival in pediatric acute myeloid leukemia: a report from the Children ' s Oncology Group

Neutrophil elastase, a serine protease of the chymotrypsin family encoded by ELANE (ELA2), is primarily found in azurophilic (primary) granules of neutrophils [1,2]. Physiologically, neutrophil elastase plays a role as an intracellular microbicidal agent that, after release, remains exposed at the cell surface and contributes to the extracellular killing of microorganisms; the protease also regulates immune responses by activating specific cell surface receptors and modulating the cytokine network [1,2].