title: Pathogen sensing pathways in human embryonic stem cell derived-endothelial cells: role of NOD1 receptors.
abstract: Human embryonic stem cell-derived endothelial cells (hESC-EC), as well as other stem cell derived endothelial cells, have a range of applications in cardiovascular research and disease treatment. Endothelial cells sense Gram-negative bacteria via the pattern recognition receptors (PRR) Toll-like receptor (TLR)-4 and nucleotide-binding oligomerisation domain-containing protein (NOD)-1. These pathways are important in terms of sensing infection, but TLR4 is also associated with vascular inflammation and atherosclerosis. Here, we have compared TLR4 and NOD1 responses in hESC-EC with those of endothelial cells derived from other stem cells and with human umbilical vein endothelial cells (HUVEC). HUVEC, endothelial cells derived from blood progenitors (blood outgrowth endothelial cells; BOEC), and from induced pluripotent stem cells all displayed both a TLR4 and NOD1 response. However, hESC-EC had no TLR4 function, but did have functional NOD1 receptors. In vivo conditioning in nude rats did not confer TLR4 expression in hESC-EC. Despite having no TLR4 function, hESC-EC sensed Gram-negative bacteria, a response that was found to be mediated by NOD1 and the associated RIP2 signalling pathways. Thus, hESC-EC are TLR4 deficient but respond to bacteria via NOD1. This data suggests that hESC-EC may be protected from unwanted TLR4-mediated vascular inflammation, thus offering a potential therapeutic advantage.
authors.affiliation: Department of Cardiothoracic Pharmacology, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Reed
authors.affiliation: Department of Cardiac Pharmacology, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom; Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Gabor
authors.initials: G
authors.lastname: Foldes
authors.affiliation: Department of Cardiothoracic Pharmacology, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Timothy
authors.initials: T
authors.lastname: Gatheral
authors.affiliation: Airway Disease Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Koralia E
authors.initials: KE
authors.lastname: Paschalaki
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Lendvai
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Bagyura
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Tamas
authors.initials: T
authors.lastname: Nemeth
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Judit
authors.initials: J
authors.lastname: Skopal
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Bela
authors.initials: B
authors.lastname: Merkely
authors.affiliation: MRC and Asthma UK Centre in Allergic Mechanisms of Asthma and Centre for Respiratory Infection, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Aurica G
authors.initials: AG
authors.lastname: Telcian
authors.affiliation: MRC and Asthma UK Centre in Allergic Mechanisms of Asthma and Centre for Respiratory Infection, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Leila
authors.initials: L
authors.lastname: Gogsadze
authors.affiliation: MRC and Asthma UK Centre in Allergic Mechanisms of Asthma and Centre for Respiratory Infection, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Edwards
authors.affiliation: Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Philadelphia, Pennsylvania, United States of America.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Gough
authors.affiliation: Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Philadelphia, Pennsylvania, United States of America.
authors.forename: John
authors.initials: J
authors.lastname: Bertin
authors.affiliation: MRC and Asthma UK Centre in Allergic Mechanisms of Asthma and Centre for Respiratory Infection, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Sebastian L
authors.initials: SL
authors.lastname: Johnston
authors.affiliation: Department of Cardiac Pharmacology, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom.
authors.forename: Sian E
authors.initials: SE
authors.lastname: Harding
authors.affiliation: Department of Cardiothoracic Pharmacology, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Mitchell
mesh_terms: D000818:Animals; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism* / Q000382:microbiology*; D055785:Gene Knockdown Techniques; D006192:Haemophilus Infections / Q000382:microbiology; D006193:Haemophilus influenzae / Q000502:physiology*; D000066449:Human Embryonic Stem Cells / Q000166:cytology* / Q000382:microbiology*; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism / Q000382:microbiology; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000378:metabolism; D053474:Nod1 Signaling Adaptor Protein / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D011923:Rats, Nude; D053475:Receptor-Interacting Protein Serine-Threonine Kinase 2 / Q000378:metabolism; D033581:Stem Cell Transplantation; D051197:Toll-Like Receptor 4 / Q000378:metabolism
chemical_list: C119067:NOD1 protein, human; D053474:Nod1 Signaling Adaptor Protein; D034741:RNA, Small Interfering; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; C506253:RIPK2 protein, human; D053475:Receptor-Interacting Protein Serine-Threonine Kinase 2