Neutrophil extracellular trap induction by alcohol generates unique low-density neutrophils with defective functions and impaired clearance contributing to liver damage in alcoholic hepatitis

Alcoholic hepatitis (AH) is characterized by severe liver and systemic inflammation and high mortality. Although numerous studies correlated neutrophil counts with poor clinical outcomes, the role of neutrophils in AH is poorly understood. Here, we report that neutrophils contribute to liver damage through increased neutrophils extracellular traps (NET) production in AH patients and mouse models with a concordant significant increase of low-density neutrophils (LDNs) in AH patients. Transcriptome analysis revealed that high-density neutrophils (HDNs) are activated and more prone to release NET, whereas LDNs exhibit exhausted phenotype. We show that alcohol-induced NET release in HDNs induces a unique LDN subset with decreased functionality and reduced clearance. Elimination of both defective HDNs and LDNs through in vivo neutrophil depletion or prevention of NET production with granulocyte colony stimulating factor (G-CSF) treatment ameliorate alcohol-induced liver damage. Our findings uncover alcohol-induced neutrophil phenotypic changes and provide mechanistic insights for therapeutic interventions in AH. Overall design: Whole transcriptome sequencing of high-density neutrophils (HDNs) and low-density neutrophils (LDNs) isolated from collected blood of acute alcoholic hepatitis patients (n=4) and HDNs from healthy human subjects (n=3).