Retinoic acid‐inducible gene‐I, melanoma differentiation‐associated gene 5 and C‐X‐C motif chemokine ligand 10 are induced by a Toll‐like receptor 3 agonist in human brain microvascular endothelial cells. Issue 3 (11th May 2018)

• Record Type: Journal Article
• Authors: Imaizumi, Tadaatsu; Arai, Akine; Kawaguchi, Shogo; Hayakari, Ryo; Matsumiya, Tomoh; Seya, Kazuhiko; Yoshida, Hidemi; Tanaka, Hiroshi
• Is Part Of: Clinical & experimental neuroimmunology. Volume 9:Issue 3(2018)
• Page Start: 189
• Page End: 197
• Publication Date: 2018-05-11
• Subjects: brain microvascular endothelial cells -- C‐X‐C motif chemokine ligand 10 -- melanoma differentiation‐associated gene 5 -- retinoic acid‐inducible gene‐I -- Toll‐like receptor 3; 616.80479
• DOI: 10.1111/cen3.12463
• Languages: English
• ISSNs: 1759-1961

Abstract

Abstract: Objective: Brain microvascular endothelial cells (BMEC) are the major component of the blood–brain barrier, and play a critical role in protecting the brain from pathogens. Although Toll‐like receptor 3 (TLR3) is known as an important pattern‐recognition receptor against viral double‐stranded RNA, the downstream reactions of TLR3 in human BMEC are not fully characterized. The purpose of the present study was to investigate the role of TLR3 signaling in the expression of retinoic acid‐inducible gene‐I (RIG‐I), melanoma differentiation‐associated gene 5 (MDA5) and C‐X‐C motif chemokine ligand 10 (CXCL10) in human BMEC. Methods: The hCMEC/D3 cells, a human BMEC cell line, were cultured and stimulated with polyinosinic‐polycytidylic acid, a synthetic TLR3 agonist. Quantitative real‐time reverse transcription polymerase chain reaction, western blotting and enzyme‐linked immunosorbent assay were used to examine the expression of interferon‐β, RIG‐I and CXCL10. RNA interference against TLR3, interferon‐β, RIG‐I or MDA5 was also carried out. Results: Expression of RIG‐I, MDA5 and CXCL10 were induced by polyinosinic‐polycytidylic acid, and this was inhibited by knockdown of either TLR3 or interferon‐β. Knockdown of RIG‐I or MDA5 did not affect the CXCL10 expression in the early phase (4 h), but decreased the CXCL10 induction in the late phase (8 or 24 h). Conclusions: RIG‐I, MDA5 and CXCL10 are induced through TLR3 activation in hCMEC/D3 cells, and RIG‐I and MDA5 might function to enhance and/or prolong the reactions mediated by CXCL10. These molecules might play a distinct role in innate immune reactions against double‐stranded RNA viruses in human BMEC. Abstract : TLR3 signaling induces RIG‐I, MDA5 and CXCL10 in hCMEC/D3 human brain microvascular endothelial cells. IFN‐beta is involved in the expression of RIG‐I, MDA5 and CXCL10. RIG‐I and MDA5 are involved in CXCL10 induction in late phase of this reaction.