title: Formation of a stable mimic of ambient particulate matter containing viable infectious respiratory syncytial virus and its dry-deposition directly onto cell cultures.
abstract: Epidemiological associations of worse respiratory outcomes from combined exposure to ambient particulate matter (PM) and respiratory viral infection suggest possible interactions between PM and viruses. To characterize outcomes of such exposures, we developed an in vitro mimic of the in vivo event of exposure to PM contaminated with respiratory syncytial virus (RSV). Concentration of infectious RSV stocks and a particle levitation apparatus were the foundations of the methodology developed to generate specific numbers of PM mimics (PM(Mimics)) of known composition for dry, direct deposition onto airway epithelial cell cultures. Three types of PM(Mimics) were generated for this study: (i) carbon alone (P(C)), (ii) carbon and infectious RSV (P(C+RSV)), and (iii) aerosols consisting of RSV (A(RSV)). P(C+RSV) were stable in solution and harbored infectious RSV for up to 6 months. Unlike A(RSV) infection, P(C+RSV) infection was found to be dynamin dependent and to cause lysosomal rupture. Cells dosed with PM(Mimics) comprised of RSV (A(RSV)), carbon (P(C)), or RSV and carbon (P(C+RSV)) responded differentially as exemplified by the secretion patterns of IL-6 and IL-8. Upon infection, and prior to lung cell death due to viral infection, regression analysis of these two mediators in response to incubation with A(RSV), P(C), or P(C+RSV) yielded higher concentrations upon infection with the latter and at earlier time points than the other PM(Mimics). In conclusion, this experimental platform provides an approach to study the combined effects of PM-viral interactions and airway epithelial exposures in the pathogenesis of respiratory diseases involving inhalation of environmental agents.
authors.affiliation: Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada, V5A 1S6.
authors.forename: Teresita M
authors.initials: TM
authors.lastname: Cruz-Sanchez
authors.forename: Allen E
authors.initials: AE
authors.lastname: Haddrell
authors.forename: Tillie L
authors.initials: TL
authors.lastname: Hackett
authors.forename: Gurpreet K
authors.initials: GK
authors.lastname: Singhera
authors.forename: David
authors.initials: D
authors.lastname: Marchant
authors.forename: Ryan
authors.initials: R
authors.lastname: Lekivetz
authors.forename: Anna
authors.initials: A
authors.lastname: Meredith
authors.forename: Derrick
authors.initials: D
authors.lastname: Horne
authors.forename: Darryl A
authors.initials: DA
authors.lastname: Knight
authors.forename: Stephen F
authors.initials: SF
authors.lastname: van Eeden
authors.forename: Tony R
authors.initials: TR
authors.lastname: Bai
authors.forename: Richard G
authors.initials: RG
authors.lastname: Hegele
authors.forename: Delbert R
authors.initials: DR
authors.lastname: Dorscheid
authors.forename: George R
authors.initials: GR
authors.lastname: Agnes
mesh_terms: D006801:Humans; D010316:Particle Size; D052638:Particulate Matter / Q000737:chemistry*; D018357:Respiratory Syncytial Virus Infections; D012136:Respiratory Syncytial Viruses / Q000737:chemistry* / Q000302:isolation & purification; D013499:Surface Properties; D014407:Tumor Cells, Cultured
chemical_list: D052638:Particulate Matter