Endosomal trafficking inhibitor EGA can control TLR7-mediated IFNα expression by human plasmacytoid dendritic cells

Autor: Matthew J. Wiest, Laurie Baert, Chao Gu, Kevin M. Gayler, Hyoungjun Ham, Laurent Gorvel, Mira T. Keddis, Leroy W. Griffing, HyeMee Joo, Jean-Pierre Gorvel, Daniel D. Billadeau, Robert R. Kane, SangKon Oh
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Frontiers in Immunology, Vol 14 (2023)
Druh dokumentu: article
ISSN: 1664-3224
DOI: 10.3389/fimmu.2023.1202197
Popis: Plasmacytoid dendritic cells (pDC) are the major producer of type 1 IFN in response to TLR7 agonists. Aberrant TLR7 activation and type 1 IFN expression by pDCs are linked to the pathogenesis of certain types of autoimmune diseases, including systemic lupus erythematosus (SLE). This study investigated the underlying mechanisms for TLR7-mediated cytokine expression by pDCs using a late endosome trafficking inhibitor, EGA (4-bromobenzaldehyde N-(2,6-dimethylphenyl) semicarbazone). We found that EGA treatment decreased IFNα expression by pDCs stimulated with imiquimod (R837), single-stranded RNA40, and influenza virus. EGA also decreased TNFα expression and secretion by R837-stimulated pDCs. Mechanistically, EGA treatment decreased phosphorylation of IKKα/β, STAT1, and p38, and prolonged degradation of IκBα. Furthermore, EGA treatment decreased the colocalization of 3F, a substituted adenine TLR7 agonist, with LAMP1+ compartments in pDCs. EGA was also capable of diminishing IFNα expression by SLE pDCs treated with R837 or live PR8/A/34 influenza viruses. Therefore, we concluded that trafficking of TLR7 agonists to LAMP1+ compartments is important for IFNα expression by pDCs. Data from this study support additional examinations of the potential benefits of EGA in treating type 1 IFN-associated inflammatory diseases in the future.
Databáze: Directory of Open Access Journals