How neutrophils kill microbes.
Neutrophils provide the first line of defense of the innate immune system by phagocytosing, killing, and digesting bacteria and fungi. Killing was previously believed to be accomplished by oxygen free radicals and other reactive oxygen species generated by the NADPH oxidase, and by oxidized halides produced by myeloperoxidase. We now know this is incorrect. The oxidase pumps electrons into the phagocytic vacuole, thereby inducing a charge across the membrane that must be compensated. The movement of compensating ions produces conditions in the vacuole conducive to microbial killing and digestion by enzymes released into the vacuole from the cytoplasmic granules.
Segal
Anthony W
AW
Center for Molecular Medicine, University College London, London WC1E 6JJ, United Kingdom. t.segal@ucl.ac.uk
D000818:Animals; D004579:Electron Transport; D006801:Humans; D007113:Immunity, Innate; D008854:Microscopy, Electron; D018448:Models, Immunological; D019255:NADPH Oxidases / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D010587:Phagocytosis; D017382:Reactive Oxygen Species / Q000378:metabolism; D014617:Vacuoles / Q000378:metabolism
D017382:Reactive Oxygen Species; D019255:NADPH Oxidases