Article pubs.acs.org/ac
Formation of a Stable Mimic of Ambient Particulate Matter Containing Viable Infectious Respiratory Syncytial Virus and Its Dry-Deposition Directly onto Cell Cultures Teresita M. Cruz-Sanchez,† Allen E. Haddrell,† Tillie L. Hackett,‡,§ Gurpreet K. Singhera,‡ David Marchant,‡ Ryan Lekivetz,∥ Anna Meredith,‡ Derrick Horne,⊥ Darryl A. Knight,‡,§ Stephen F. van Eeden,‡ Tony R. Bai,‡ Richard G. Hegele,⊗ Delbert R. Dorscheid,‡ and George R. Agnes*,† †
Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada, V5A 1S6 James Hogg Research Centre, Providence Heart + Lung Institute at St. Paul’s Hospital, University of British Columbia, Vancouver, British Columbia, Canada, V6Z 1Y6 § Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, Canada, V6T 1Z3 ∥ Department of Statistics, Simon Fraser University, Burnaby, British Columbia, Canada, V5A 1S6 ⊥ Botany Department, UBC BioImaging Facility, University of British Columbia, Vancouver BC V6T 1Z4 ⊗ Department of Laboratory Medicine and Pathobiology, University of Toronto, Canada M5S 1A8 ‡
S Supporting Information *
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 (PMMimics) of known composition for dry, direct deposition onto airway epithelial cell cultures. Three types of PMMimics were generated for this study: (i) carbon alone (PC), (ii) carbon and infectious RSV (PC+RSV), and (iii) aerosols consisting of RSV (ARSV). PC+RSV were stable in solution and harbored infectious RSV for up to 6 months. Unlike ARSV infection, PC+RSV infection was found to be dynamin dependent and to cause lysosomal rupture. Cells dosed with PMMimics comprised of RSV (ARSV), carbon (PC), or RSV and carbon (PC+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 ARSV, PC, or PC+RSV yielded higher concentrations upon infection with the latter and at earlier time points than the other PMMimics. 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.
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as airborne virions are presented to a host, either alone or harbored in ambient particles, is a technical challenge.12,13 We use an alternating current (ac) particle levitation trap similar to what we have built and described previously, but with incremental changes in the methodology to enable creation of virus-containing PM mimics (PMMimics) and their dry deposition directly onto a differentiated primary airway epithelium grown on air−liquid interfaces (ALI) (Figure 1).14 Levitation trap technology has been applied to the study of cellular responses elicited by specific chemical and biological components in PM10 as it allows for the creation of particles of desired size and
mbient particulate matter, comprised of numerous different compounds each at different abundances and measuring
