NETosis is a ROS-dependent PCD driven by neutrophil extracellular traps (NETs) in response to various infections, which was first described by A. Zychlinsky in 2004.208 Peptidylarginine deiminase 4 (PAD4), neutrophil elastase (NE), GSDMD, and free DNA greatly participate in the whole process of NETosis.209 NETs are complex networks comprised of DNA containing histones, myeloperoxidase (MPO), and NE.210. Here, MPO is linked to infection.