Src Reduces Neutrophil Extracellular Traps Generation and Resolves Acute Organ Damage

Neutrophil extracellular traps (NETs) are key factors mediating acute inflammatory injury. However, the underlying mechanisms and potential therapeutic targets remain unclear. Previous results suggest Src may be involved in regulating the NETs formation. Here, Src is found activated in the NETs model in vitro, in the murine- and human-derived neutrophils (acute pancreatitis and sepsis). Moreover, p-Src expression correlates with the clinical prognosis of acute pancreatitis and sepsis patients. Meanwhile, the inhibition of Src activity (gene silencing or inhibitors) inhibits NETs formation in vitro. Mechanistically, Src directly activates RAF1 by regulating phosphorylation at the Ser 621 site and mediates the RAF/MEK/ERK pathway, thereby affecting the intracellular ROS production. Alternatively, Src activates the RAF/MEK/ERK pathway by mediating PKC phosphorylation. In vivo, neutrophil Src - specific defect significantly reduces acute inflammatory response, organ damage, and the NETs formation in damaged tissue. Eventually, Src inhibitors are used and validated their pharmacological effects. These results identify Src as a key mediator in intracellular ROS production, NETs formation, and acute organ injury. Hence, Src inhibition may represent a promising therapeutic strategy for treating acute organ injury.