Inflammation / Inflammatory Diseases & Neutrophils / Neutrophilic Granulocytes

Neutrophils / Neutrophilic Granulocytes are the most common immune cells found where there is inflammation. They were once thought to only have the job of attacking and killing harmful invaders using three main methods: swallowing and destroying them with oxidative stress, releasing substances from their granules, and creating structures called neutrophil extracellular traps (NETs)
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Green et al. 2014 Free Radic Biol Med 77: 49-56

However, we now understand that neutrophils are more complex. They are active in gene expression and metabolism, playing roles in both promoting and reducing inflammation. The process of releasing Neutrophil extracellular traps (NETs), known as NETosis, shows this complexity. NETs stick to bacteria to stop them from spreading, directly kill bacteria, and help other immune cells called macrophages to kill bacteria more effectively.
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Pilsczek et al. 2010 J Immunol 185: 7413-7425
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But, if there is too much NETosis, it can harm the body's own tissues, especially during conditions like sepsis and autoimmune diseases. A distinct subset of proinflammatory neutrophils, which are isolated from patients with systemic lupus erythematosus, induces vascular damage and synthesizes type I IFNs. Neutrophils that form nets cause damage to the endothelium, infiltrate tissues, and reveal molecules that stimulate the immune system in systemic lupus erythematosus. The impairment of neutrophil extracellular trap degradation is linked to lupus nephritis.
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Jiménez-Alcázar et al. 2017 Science 358: 1202–1206
Colón et al. 2019 Crit Care 23: 113
Qu et al. 2022 Cell Death Discov 8: 375

Neutrophils / Neutrophilic Granulocytes have elegant defense mechanisms to eliminate microbes that have translocated across a single layer of mucosal epithelial cells
Fournier & Parkos 2012 Mucosal Immunology 5(4): 354

During the inflammatory response, neutrophils also contribute to the recruitment of other immune cells and facilitate mucosal healing by releasing mediators necessary for the resolution of inflammation
Fournier & Parkos 2012 Mucosal Immunology 5(4): 354

During inflammation, SCFA stimulate the migration of neutrophils by activating GPR43 and modulate their production of reactive oxygen species and phagocytosis
Vinolo et al., 2009a Cell Biochem Funct. 27(1):48–55

see also:
Adiposity / Obesity & Inflammation / Inflammatory Diseases
Antimicrobial peptides (AMPs)
Defending the Attack of Pathogens by Neutrophils
Defensins
G-Protein Coupled Receptor 43 (GPR43) & Neutrophils / Neutrophilic Granulocytes
Interferons Type I (IFN Type I)
LL-37 / Cathelicidin antimicrobial peptide
NETosis
Pathogenicity & Staphylococcus aureus
Protegrins
Staphylococcus aureus
Systemic Lupus Erythematosus (SLE)