fig1

Figure 1. Three defense functions of neutrophils: phagocytosis, degranulation, and NETosis. (I) Phagocytosis: Neutrophils engulf invading pathogens, releasing cytoplasmic granules (such as antimicrobial peptides) upon contact with the engulfed pathogen, thereby facilitating the degradation and elimination of the pathogen; (II) Degranulation: Activated neutrophils release granules stored in the cytoplasm into the extracellular space, acting on extracellular pathogens, leading to their destruction and clearance; (III) NETosis: Activated neutrophils release NETs composed of proteins (such as histones, NE, and MPO) and DNA, which physically capture and eliminate pathogens. Created with BioRender.com (accessed on 30 June 2022). NETs: Neutrophils extracellular traps; NE: neutrophil elastase; MPO: myeloperoxidase; DNA: deoxyribonucleic acid.