Disrupted degradative sorting of TLR7 is associated with human lupus
- PMID: 38207015
- DOI: 10.1126/sciimmunol.adi9575
Disrupted degradative sorting of TLR7 is associated with human lupus
Abstract
Hyperactive TLR7 signaling has long been appreciated as driver of autoimmune disease in mouse models. Recently, gain-of-function mutations in TLR7 were identified as a monogenic cause of human lupus. TLR7 is an intracellular transmembrane receptor, sensing RNA breakdown products within late endosomes. Here, we show that endosome dysfunction leads to unrestricted TLR7 signaling and is associated with human lupus. The late endosomal BORC complex together with the small GTPase Arl8b controls intracellular TLR7 levels by regulating receptor turnover. This requires a direct interaction between the TLR7-associated trafficking factor Unc93b1 and Arl8b. We identified an UNC93B1 mutation in a patient with childhood-onset lupus, which results in reduced BORC interaction and endosomal TLR7 accumulation. Therefore, a failure to control TLR7 turnover is sufficient to break immunological tolerance to nucleic acids. Our results highlight the importance of an intact endomembrane system in preventing pathological TLR7 signaling and autoimmune disease.
Similar articles
-
Unc93B1 biases Toll-like receptor responses to nucleic acid in dendritic cells toward DNA- but against RNA-sensing.J Exp Med. 2009 Jun 8;206(6):1339-50. doi: 10.1084/jem.20082316. Epub 2009 May 18. J Exp Med. 2009. PMID: 19451267 Free PMC article.
-
UNC93B1 variants underlie TLR7-dependent autoimmunity.Sci Immunol. 2024 Feb 23;9(92):eadi9769. doi: 10.1126/sciimmunol.adi9769. Epub 2024 Feb 23. Sci Immunol. 2024. PMID: 38207055
-
UNC93B1 recruits syntenin-1 to dampen TLR7 signalling and prevent autoimmunity.Nature. 2019 Nov;575(7782):366-370. doi: 10.1038/s41586-019-1612-6. Epub 2019 Sep 23. Nature. 2019. PMID: 31546246 Free PMC article.
-
TLR7 Signaling in Lupus B Cells: New Insights into Synergizing Factors and Downstream Signals.Curr Rheumatol Rep. 2021 Nov 24;23(11):80. doi: 10.1007/s11926-021-01047-1. Curr Rheumatol Rep. 2021. PMID: 34817709 Free PMC article. Review.
-
Regulatory molecules required for nucleotide-sensing Toll-like receptors.Immunol Rev. 2009 Jan;227(1):32-43. doi: 10.1111/j.1600-065X.2008.00729.x. Immunol Rev. 2009. PMID: 19120473 Review.
Cited by
-
Mechanisms underlying sex differences in autoimmunity.J Clin Invest. 2024 Sep 17;134(18):e180076. doi: 10.1172/JCI180076. J Clin Invest. 2024. PMID: 39286970 Free PMC article. Review.
-
Monogenic lupus - from gene to targeted therapy.Mol Cell Pediatr. 2024 Sep 12;11(1):8. doi: 10.1186/s40348-024-00181-x. Mol Cell Pediatr. 2024. PMID: 39264482 Free PMC article. Review.
-
Systemic lupus erythematosus genetics: insights into pathogenesis and implications for therapy.Nat Rev Rheumatol. 2024 Oct;20(10):635-648. doi: 10.1038/s41584-024-01152-2. Epub 2024 Sep 4. Nat Rev Rheumatol. 2024. PMID: 39232240 Review.
-
NADPH oxidase in B cells and macrophages protects against murine lupus by regulation of TLR7.JCI Insight. 2024 Jul 23;9(16):e178563. doi: 10.1172/jci.insight.178563. JCI Insight. 2024. PMID: 39042716 Free PMC article.
-
The immunology of systemic lupus erythematosus.Nat Immunol. 2024 Aug;25(8):1332-1343. doi: 10.1038/s41590-024-01898-7. Epub 2024 Jul 15. Nat Immunol. 2024. PMID: 39009839 Review.
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Medical