title: Cellular crosstalk between airway epithelial and endothelial cells regulates barrier functions during exposure to double-stranded RNA.
abstract: The epithelial and endothelial barriers of the airway mucosa are critical for regulation of tissue homeostasis and protection against pathogens or other tissue damaging agents. In response to a viral infection, epithelial cells must signal to the endothelium to initiate immune cell recruitment. This is a highly temporal regulated process; however, the mechanisms of this cross-talk are not fully understood.
  
  
  
  In a close-contact co-culture model of human airway epithelial and endothelial cells, cellular crosstalk was analyzed using transepithelial electrical resistance (TER) measurements, immunofluorescence, electron microscopy, and ELISA. Viral infections were simulated by exposing airway epithelial cells apically to double-stranded RNA (Poly(I:C)). Using a microfluidic culture system, the temporal release of mediators was analyzed in the co-culture model.
  
  
  
  Within 4 h of challenge, double-stranded RNA induced the release of TNF-α by epithelial cells. This activated endothelial cells by triggering the release of the chemoattractant CX3CL1 (fractalkine) by 8 h post-challenge and expression of adhesion molecules E-selectin and ICAM-1. These responses were significantly reduced by neutralising TNF-α.
  
  
  
  By facilitating kinetic profiling, the microfluidic co-culture system has enabled identification of a key signaling mechanism between the epithelial and endothelial barriers. Better understanding of cell-cell cross-talk and its regulatory mechanisms has the potential to identify new therapeutic strategies to control airway inflammation.
authors.affiliation: Academic Unit of Clinical and Experimental Sciences Faculty of Medicine University of Southampton Southampton United Kingdom.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Blume
authors.affiliation: Electronics and Computer Sciences Faculty of Physical and Applied Sciences University of Southampton Southampton United Kingdom.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Reale
authors.affiliation: Electronics and Computer Sciences Faculty of Physical and Applied Sciences University of Southampton Southampton United Kingdom.
authors.forename: Marie
authors.initials: M
authors.lastname: Held
authors.affiliation: Academic Unit of Clinical and Experimental Sciences Faculty of Medicine University of Southampton Southampton United Kingdom.
authors.forename: Matthew
authors.initials: M
authors.lastname: Loxham
authors.affiliation: Academic Unit of Clinical and Experimental Sciences Faculty of Medicine University of Southampton Southampton United Kingdom.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Millar
authors.affiliation: Academic Unit of Clinical and Experimental SciencesFaculty of MedicineUniversity of SouthamptonSouthamptonUnited Kingdom; Institute for Life SciencesUniversity of SouthamptonSouthamptonUnited Kingdom.
authors.forename: Jane E
authors.initials: JE
authors.lastname: Collins
authors.affiliation: Academic Unit of Clinical and Experimental SciencesFaculty of MedicineUniversity of SouthamptonSouthamptonUnited Kingdom; Institute for Life SciencesUniversity of SouthamptonSouthamptonUnited Kingdom; National Institute for Health ResearchSouthampton Respiratory Biomedical Research UnitUniversity Hospital SouthamptonSouthamptonUnited Kingdom.
authors.forename: Emily J
authors.initials: EJ
authors.lastname: Swindle
authors.affiliation: Electronics and Computer SciencesFaculty of Physical and Applied SciencesUniversity of SouthamptonSouthamptonUnited Kingdom; Institute for Life SciencesUniversity of SouthamptonSouthamptonUnited Kingdom.
authors.forename: Hywel
authors.initials: H
authors.lastname: Morgan
authors.affiliation: Academic Unit of Clinical and Experimental SciencesFaculty of MedicineUniversity of SouthamptonSouthamptonUnited Kingdom; Institute for Life SciencesUniversity of SouthamptonSouthamptonUnited Kingdom; National Institute for Health ResearchSouthampton Respiratory Biomedical Research UnitUniversity Hospital SouthamptonSouthamptonUnited Kingdom.
authors.forename: Donna E
authors.initials: DE
authors.lastname: Davies
mesh_terms: D001980:Bronchi / Q000166:cytology; D002450:Cell Communication; D002460:Cell Line; D002478:Cells, Cultured; D054428:Chemokine CX3CL1 / Q000378:metabolism; D018920:Coculture Techniques; D019040:E-Selectin / Q000378:metabolism; D004847:Epithelial Cells / Q000502:physiology*; D061307:Human Umbilical Vein Endothelial Cells / Q000502:physiology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D044085:Microfluidics; D011070:Poly I-C / Q000494:pharmacology; D012330:RNA, Double-Stranded / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: C515538:CX3CL1 protein, human; D054428:Chemokine CX3CL1; D019040:E-Selectin; C573420:ICAM1 protein, human; D012330:RNA, Double-Stranded; C546936:SELE protein, human; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D011070:Poly I-C
keywords: Airway epithelial barrier; cellular crosstalk; endothelial barrier; fractalkine (CX3CL1); tumor necrosis factor alpha