Scylla, Charybdis, and navigating antimicrobial action in the neutrophil phagosome

The text extracted from the initial paragraph of a paper coauthored by Zanvil Cohn, one of the pioneers in the study of leukocyte biology, highlights two phenomena that stimulated investigations of innate immunity in the middle of the last century, namely phagocytosis and intracellular antimicrobial activity. Although many features of phagocytosis have been characterized since that time, fundamental aspects of the antimicrobial action of neutrophils remain unknown. The report by Ashby et al. provides a refined and nuanced look at the interface between an ingested microbe, Staphylococcus aureus, and HOCl generated by the myeloperoxidase (MPO)-H₂ O₂ -chloride system in neutrophil phagosomes and represents a holistic approach to the analysis of bactericidal mechanisms that recognizes contributions from both phagocyte and its ingested prey.