HLJ1 amplifies endotoxin-induced sepsis severity by promoting IL-12 heterodimerization in macrophages
- National Taiwan University, Taiwan
- National Taiwan University Hospital, Taiwan
Abstract
Heat shock protein (HSP) 40 has emerged as a key factor in both innate and adaptive immunity, whereas the role of HLJ1, a molecular chaperone in HSP40 family, in modulating endotoxin-induced sepsis severity is still unclear. During LPS-induced endotoxic shock, HLJ1 knockout mice shows reduced organ injury and IFN-γ-dependent mortality. Using single-cell RNA sequencing, we characterize mouse liver nonparenchymal cell populations under LPS stimulation, and show that HLJ1 deletion affected IFN-γ-related gene signatures in distinct immune cell clusters. In CLP models, HLJ1 deletion reduces IFN-γ expression and sepsis mortality rate when mice are treated with antibiotics. HLJ1 deficiency also leads to reduced serum levels of IL-12 in LPS-treated mice, contributing to dampened production of IFN-γ in natural killer cells but not CD4+ or CD8+ T cells, and subsequently to improved survival rate. Adoptive transfer of HLJ1-deleted macrophages into LPS-treated mice results in reduced IL-12 and IFN-γ levels and protects the mice from IFN-γ-dependent mortality. In the context of molecular mechanisms, HLJ1 is an LPS-inducible protein in macrophages and converts misfolded IL-12p35 homodimers to monomers, which maintains bioactive IL-12p70 heterodimerization and secretion. This study suggests HLJ1 causes IFN-γ-dependent septic lethality by promoting IL-12 heterodimerization, and targeting HLJ1 has therapeutic potential in inflammatory diseases involving activated IL-12/IFN-γ axis.
Data availability
The raw and processed 10x single-cell sequencing data generated in this study have been deposited in the NCBI GEO database under accession code GSE182137. Source data files have been provided for figures and figure supplements.
Article and author information
Author details
Funding
Ministry of Science and Technology, Taiwan (MOST110-2314-B-002-269)
- Kang-Yi Su
Ministry of Science and Technology, Taiwan (MOST105-2628-B-002-051-MY3)
- Kang-Yi Su
Ministry of Science and Technology, Taiwan (MOST111-2628-B-002-029-MY3)
- Kang-Yi Su
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental procedures performed were approved by the Institutional Animal Care and Use Committee (IACUC) with IACUC number 20120515, 20201050 and 20220115 at National Taiwan University Medical College.
Copyright
© 2022, Luo et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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HLJ1 amplifies endotoxin-induced sepsis severity by promoting IL-12 heterodimerization in macrophages
eLife 11:e76094.
https://doi.org/10.7554/eLife.76094
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