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Erschienen in: Current Rheumatology Reports 11/2021

01.11.2021 | Systemic Lupus Erythematosus (G Tsokos, Section Editor)

TLR7 Signaling in Lupus B Cells: New Insights into Synergizing Factors and Downstream Signals

verfasst von: Anne B. Satterthwaite

Erschienen in: Current Rheumatology Reports | Ausgabe 11/2021

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Abstract

Purpose of the Review

Systemic lupus erythematosus (SLE) is driven by nucleic acid-containing antigens that stimulate endosomal TLRs. We review new advances in our understanding of how TLR7 signaling in B cells drives autoimmunity.

Recent Findings

Pathogenic B cell responses to TLR7 engagement are shaped by the disease-associated cytokine environment. TLR7, IFNγ, and IL-21 together promote the formation of autoreactive germinal centers and the ABC/DN2 B cell subset. BAFF and type 1 IFNs enhance autoantibody production from transitional B cells in concert with TLR7. TLR7 signaling components STAT1, BANK1, IRF5, SLC15A4, and CXorf21/TASL are associated genetically with SLE and important for lupus development in mice, while role of T-bet is controversial. Proper control of TLR7 trafficking by UNC93B1, syntenin-1, and αvβ3 integrin is critical for preventing autoimmunity.

Summary

A better understanding of TLR7 signaling has revealed potential new therapeutic approaches for SLE, several of which are being tested in animal models or clinical trials.
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Metadaten
Titel
TLR7 Signaling in Lupus B Cells: New Insights into Synergizing Factors and Downstream Signals
verfasst von
Anne B. Satterthwaite
Publikationsdatum
01.11.2021
Verlag
Springer US
Erschienen in
Current Rheumatology Reports / Ausgabe 11/2021
Print ISSN: 1523-3774
Elektronische ISSN: 1534-6307
DOI
https://doi.org/10.1007/s11926-021-01047-1

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