• Meihong Deng, Yiting Tang, Wenbo Li, Xiangyu Wang, Rui Zhang, Xianying Zhang, Xin Zhao, Jian Liu, Cheng Tang, Zhonghua Liu, Yongzhuo Huang, Huige Peng, Lehui Xiao, Daolin Tang, Melanie J Scott, Qingde Wang, Jing Liu, Xianzhong Xiao, Simon Watkins, Jianhua Li, Huan Yang, Haichao Wang, Fangping Chen, Kevin J Tracey, Timothy R Billiar, and Ben Lu.
• Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
• Immunity. 2018 Oct 16; 49 (4): 740-753.e7.

AbstractCaspase-11, a cytosolic endotoxin (lipopolysaccharide: LPS) receptor, mediates pyroptosis, a lytic form of cell death. Caspase-11-dependent pyroptosis mediates lethality in endotoxemia, but it is unclear how LPS is delivered into the cytosol for the activation of caspase-11. Here we discovered that hepatocyte-released high mobility group box 1 (HMGB1) was required for caspase-11-dependent pyroptosis and lethality in endotoxemia and bacterial sepsis. Mechanistically, hepatocyte-released HMGB1 bound LPS and targeted its internalization into the lysosomes of macrophages and endothelial cells via the receptor for advanced glycation end-products (RAGE). Subsequently, HMGB1 permeabilized the phospholipid bilayer in the acidic environment of lysosomes. This resulted in LPS leakage into the cytosol and caspase-11 activation. Depletion of hepatocyte HMGB1, inhibition of hepatocyte HMGB1 release, neutralizing extracellular HMGB1, or RAGE deficiency prevented caspase-11-dependent pyroptosis and death in endotoxemia and bacterial sepsis. These findings indicate that HMGB1 interacts with LPS to mediate caspase-11-dependent pyroptosis in lethal sepsis.Copyright © 2018 Elsevier Inc. All rights reserved.

40 keywords...

hide…