Chemokine C-X-C ligand 16 (CXCL16),a single-pass Type Ⅰ membrane protein belonging to the CXC chemokine family,is related to the inflammatory response in liver injury.In present study,we investigated the pathophysiological role of CXCL16,a unique membrane-bound chemokine,in acetaminophen (APAP)-induced hepatotoxicity in mice.Mice were injected with APAP,and blood and tissue samples were harvested at different time points.The serum high-mobility group box 1 and CXCL16 levels were quantified by sandwich immunoassays.The liver tissue sections were stained with hematoxylin-eosin or with dihydroethidium staining.The expressions of CXCL16 and other cytokines were examined by real-time polymerase chain reaction.Ly6-B,p-jun N-terminal kinase (p-JNK),and JNK expressions were measured by weste blot analysis.Intracellular glutathione,reactive oxygen species,and malondialdehyde levels were also measured.APAP overdose increased hepatic CXCL16 mRNA and serum CXCL16 protein levels.CXCL16-deficient mice exhibited significantly less liver injury and hepatic necrosis,as well as a lower mortality than wild-type (WTr) mice in response to APAP-overdose treatment.APAP elevated the production of oxidative stress and decreased mitochondrial respiratory chain activation in WT mice,which was strongly reversed in CXCL16-knockout mice.In addition,CXCL16 deficiency inhibited the neutrophil infiltration and the production of proinflammatory cytokines triggered by APAP-overdose treatment.Our study revealed that CXCL16 is a critical regulator of liver immune response to APAP-induced hepatotoxicity,thus providing a potential strategy for the treatment of drug-induced acute liver failure by targeting CXCL16.