Redox modifications of cysteine residues regulate the cytokine activity of HMGB1.

Yang, Huan, Lundbäck, Peter, Ottosson, Lars, Erlandsson-Harris, Helena, Venereau, Emilie, Bianchi, Marco E, Al-Abed, Yousef, Andersson, Ulf, Tracey, Kevin J (June 2021) Redox modifications of cysteine residues regulate the cytokine activity of HMGB1. Molecular Medicine, 27 (1). p. 58. ISSN 1076-1551

[img] PDF

Download (1MB)
DOI: 10.1186/s10020-021-00307-1


BACKGROUND: High mobility group box 1 (HMGB1) is a nuclear protein with extracellular inflammatory cytokine activity. It is passively released during cell death and secreted by activated cells of many lineages. HMGB1 contains three conserved redox-sensitive cysteine residues: cysteines in position 23 and 45 (C23 and C45) can form an intramolecular disulfide bond, whereas C106 is unpaired and is essential for the interaction with Toll-Like Receptor (TLR) 4. However, a comprehensive characterization of the dynamic redox states of each cysteine residue and of their impacts on innate immune responses is lacking. METHODS: Primary human macrophages or murine macrophage-like RAW 264.7 cells were activated in cell cultures by redox-modified or point-mutated (C45A) recombinant HMGB1 preparations or by lipopolysaccharide (E. coli.0111: B4). Cellular phosphorylated NF-κB p65 subunit and subsequent TNF-α release were quantified by commercial enzyme-linked immunosorbent assays. RESULTS: Cell cultures with primary human macrophages and RAW 264.7 cells demonstrated that fully reduced HMGB1 with all three cysteines expressing thiol side chains failed to generate phosphorylated NF-КB p65 subunit or TNF-α. Mild oxidation forming a C23-C45 disulfide bond, while leaving C106 with a thiol group, was required for HMGB1 to induce phosphorylated NF-КB p65 subunit and TNF-α production. The importance of a C23-C45 disulfide bond was confirmed by mutation of C45 to C45A HMGB1, which abolished the ability for cytokine induction. Further oxidation of the disulfide isoform also inactivated HMGB1. CONCLUSIONS: These results reveal critical post-translational redox mechanisms that control the proinflammatory activity of HMGB1 and its inactivation during inflammation.

Item Type: Paper
Subjects: diseases & disorders > inflammation > cytokines
diseases & disorders > inflammation
CSHL Authors:
Communities: CSHL labs > Tracey lab
SWORD Depositor: CSHL Elements
Depositing User: CSHL Elements
Date: 7 June 2021
Date Deposited: 05 Aug 2021 14:42
Last Modified: 05 Aug 2021 15:08
PMCID: PMC8185929

Actions (login required)

Administrator's edit/view item Administrator's edit/view item
CSHL HomeAbout CSHLResearchEducationNews & FeaturesCampus & Public EventsCareersGiving