The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs

A controlled inflammatory response is required for protection against infection, but persistent inflammation causes tissue damage. Dendritic cells (DCs) have a unique capacity to promote both inflammatory and anti-inflammatory processes. One key mechanism involved in DC-mediated immunosuppression is...

Full description

Bibliographic Details
Main Authors: Salazar, Fabián, Awuah, Dennis, Negm, Ola H., Shakib, Farouk, Ghaemmaghami, Amir M.
Format: Article
Published: Nature Publishing Group 2017
Subjects:
Online Access:https://eprints.nottingham.ac.uk/41156/
_version_ 1848796209544691712
author Salazar, Fabián
Awuah, Dennis
Negm, Ola H.
Shakib, Farouk
Ghaemmaghami, Amir M.
author_facet Salazar, Fabián
Awuah, Dennis
Negm, Ola H.
Shakib, Farouk
Ghaemmaghami, Amir M.
author_sort Salazar, Fabián
building Nottingham Research Data Repository
collection Online Access
description A controlled inflammatory response is required for protection against infection, but persistent inflammation causes tissue damage. Dendritic cells (DCs) have a unique capacity to promote both inflammatory and anti-inflammatory processes. One key mechanism involved in DC-mediated immunosuppression is the expression of tryptophan-metabolizing enzyme indoleamine 2,3-dioxygenase (IDO). IDO has been implicated in diverse processes in health and disease but its role in endotoxin tolerance in human DCs is still controversial. Here we investigated the role of IDO in shaping DCs phenotype and function under endotoxin tolerance conditions. Our data show that TLR4 ligation in LPS-primed DCs, induced higher levels of both IDO isoforms together with the transcription factor aryl-hydrocarbon receptor (AhR), compared to unprimed controls. Additionally, LPS conditioning induced an anti-inflammatory phenotype in DCs - with an increase in IL-10 and higher expression of programmed death ligand (PD-L)1 and PD-L2 - which were partially dependent on IDO. Furthermore, we demonstrated that the AhR-IDO pathway was responsible for the preferential activation of noncanonical NF-κB pathway in LPS-conditioned DCs. These data provide new insight into the mechanisms of the TLR4-induced tolerogenic phenotype in human DCs, which can help the better understanding of processes involved in induction and resolution of chronic inflammation and tolerance.
first_indexed 2025-11-14T19:44:21Z
format Article
id nottingham-41156
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T19:44:21Z
publishDate 2017
publisher Nature Publishing Group
recordtype eprints
repository_type Digital Repository
spelling nottingham-411562020-05-04T18:36:18Z https://eprints.nottingham.ac.uk/41156/ The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs Salazar, Fabián Awuah, Dennis Negm, Ola H. Shakib, Farouk Ghaemmaghami, Amir M. A controlled inflammatory response is required for protection against infection, but persistent inflammation causes tissue damage. Dendritic cells (DCs) have a unique capacity to promote both inflammatory and anti-inflammatory processes. One key mechanism involved in DC-mediated immunosuppression is the expression of tryptophan-metabolizing enzyme indoleamine 2,3-dioxygenase (IDO). IDO has been implicated in diverse processes in health and disease but its role in endotoxin tolerance in human DCs is still controversial. Here we investigated the role of IDO in shaping DCs phenotype and function under endotoxin tolerance conditions. Our data show that TLR4 ligation in LPS-primed DCs, induced higher levels of both IDO isoforms together with the transcription factor aryl-hydrocarbon receptor (AhR), compared to unprimed controls. Additionally, LPS conditioning induced an anti-inflammatory phenotype in DCs - with an increase in IL-10 and higher expression of programmed death ligand (PD-L)1 and PD-L2 - which were partially dependent on IDO. Furthermore, we demonstrated that the AhR-IDO pathway was responsible for the preferential activation of noncanonical NF-κB pathway in LPS-conditioned DCs. These data provide new insight into the mechanisms of the TLR4-induced tolerogenic phenotype in human DCs, which can help the better understanding of processes involved in induction and resolution of chronic inflammation and tolerance. Nature Publishing Group 2017-03-03 Article PeerReviewed Salazar, Fabián, Awuah, Dennis, Negm, Ola H., Shakib, Farouk and Ghaemmaghami, Amir M. (2017) The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs. Scientific Reports, 7 . 43337/1-43337/11. ISSN 2045-2322 Immune tolerance Conventional dendritic cells NF-kappaB https://doi.org/10.1038/srep43337 doi:10.1038/srep43337 doi:10.1038/srep43337
spellingShingle Immune tolerance
Conventional dendritic cells
NF-kappaB
Salazar, Fabián
Awuah, Dennis
Negm, Ola H.
Shakib, Farouk
Ghaemmaghami, Amir M.
The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs
title The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs
title_full The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs
title_fullStr The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs
title_full_unstemmed The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs
title_short The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs
title_sort role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the tlr4-induced tolerogenic phenotype in human dcs
topic Immune tolerance
Conventional dendritic cells
NF-kappaB
url https://eprints.nottingham.ac.uk/41156/
https://eprints.nottingham.ac.uk/41156/
https://eprints.nottingham.ac.uk/41156/