Loss of TLR3 and its downstream signaling accelerates acinar cell damage in the acute phase of pancreatitis.
Apoptosis
Experimental acute pancreatitis
Necrosis
TRIF
Toll-like receptor 3
Journal
Pancreatology : official journal of the International Association of Pancreatology (IAP) ... [et al.]
ISSN: 1424-3911
Titre abrégé: Pancreatology
Pays: Switzerland
ID NLM: 100966936
Informations de publication
Date de publication:
Jan 2019
Jan 2019
Historique:
received:
11
09
2018
revised:
06
12
2018
accepted:
14
12
2018
pubmed:
26
12
2018
medline:
23
4
2019
entrez:
26
12
2018
Statut:
ppublish
Résumé
Acute pancreatitis is accompanied by acinar cell damage releasing potential toll-like receptor 3 (TLR3) ligands. So far, TLR3 is known as a pattern recognition receptor in the immune signaling cascade triggering a type I interferon response. In addition, TLR3 signaling contributes to programmed cell death through the activation of caspase 8. However, the functional role of TLR3 and its downstream toll-like receptor adaptor molecule 1 (TICAM1) in the inflamed pancreas is unknown. To uncover the role of TLR3 signaling in acute pancreatitis, we induced a cerulein-mediated pancreatitis in Tlr3 and Ticam1 knockout (KO) mice and in wildtype animals. The exocrine damage was determined by blood serum analysis and histological examination. Immunohistochemistry, gene expression and immunoblot analysis were conducted to study TLR3 function. After the induction of an acute pancreatitis, wildtype mice showed a high endosomal TLR3 expression in acinar cells. In comparison to wildtype and Ticam1 KO mice, Tlr3 KO mice exhibited the highest severity of pancreatitis with an increased NF-κB activation and elevated expression of the pro-inflammatory cytokines Il6 and Tnf, although the amount of infiltrating immune cells was unaffected. Additionally, we detected a strong elevation of acinar cell necrosis and reduced levels of cleaved caspase 8 in Tlr3 and Ticam1 KO mice. TLR3 and its downstream adaptor TICAM1 are important mediators of acinar cell damage in acute pancreatitis. They possess a critical role in programmed cell death and our data suggest that TLR3 signaling controls the onset and severity of acute pancreatitis.
Sections du résumé
BACKGROUND
BACKGROUND
Acute pancreatitis is accompanied by acinar cell damage releasing potential toll-like receptor 3 (TLR3) ligands. So far, TLR3 is known as a pattern recognition receptor in the immune signaling cascade triggering a type I interferon response. In addition, TLR3 signaling contributes to programmed cell death through the activation of caspase 8. However, the functional role of TLR3 and its downstream toll-like receptor adaptor molecule 1 (TICAM1) in the inflamed pancreas is unknown.
METHODS
METHODS
To uncover the role of TLR3 signaling in acute pancreatitis, we induced a cerulein-mediated pancreatitis in Tlr3 and Ticam1 knockout (KO) mice and in wildtype animals. The exocrine damage was determined by blood serum analysis and histological examination. Immunohistochemistry, gene expression and immunoblot analysis were conducted to study TLR3 function.
RESULTS
RESULTS
After the induction of an acute pancreatitis, wildtype mice showed a high endosomal TLR3 expression in acinar cells. In comparison to wildtype and Ticam1 KO mice, Tlr3 KO mice exhibited the highest severity of pancreatitis with an increased NF-κB activation and elevated expression of the pro-inflammatory cytokines Il6 and Tnf, although the amount of infiltrating immune cells was unaffected. Additionally, we detected a strong elevation of acinar cell necrosis and reduced levels of cleaved caspase 8 in Tlr3 and Ticam1 KO mice.
CONCLUSIONS
CONCLUSIONS
TLR3 and its downstream adaptor TICAM1 are important mediators of acinar cell damage in acute pancreatitis. They possess a critical role in programmed cell death and our data suggest that TLR3 signaling controls the onset and severity of acute pancreatitis.
Identifiants
pubmed: 30583980
pii: S1424-3903(18)30766-X
doi: 10.1016/j.pan.2018.12.005
pii:
doi:
Substances chimiques
Adaptor Proteins, Vesicular Transport
0
TICAM-1 protein, mouse
0
TLR3 protein, mouse
0
Toll-Like Receptor 3
0
Ceruletide
888Y08971B
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
149-157Informations de copyright
Copyright © 2018 IAP and EPC. Published by Elsevier B.V. All rights reserved.