title: Interaction and localization of synthetic nanoparticles in healthy and cystic fibrosis airway epithelial cells: effect of ozone exposure.
abstract: BACKGROUND
  Nanoparticles (NPs) produced by nanotechnology processes have taken the field of medicine by storm. Concerns about safety of these NPs in humans, however, have recently been raised. Although studies of NP toxicity have focused on lung disease the mechanistic link between NP exposure and lung injury remained unclear. This is primarily due to a lack of availability of appropriate airway disease models and sophisticated microscopic techniques to study nano-sized particulate delivery and resulting responses.
  
  
  METHODS
  Air-liquid interface (ALI) cultures of non-cystic fibrosis (CF) and CF airway epithelial cells were exposed to the FITC-labeled NPs using a PennCentury microsprayer™. Uptake of NPs was assessed by FACS. Laser scanning microscopy (LSM) was performed and the images were analyzed by an advanced imaging software to study particle deposition and uptake.
  
  
  RESULTS
  Flow cytometry data revealed that CF cells accumulated increased amounts of NPs. The increased NP uptake could be attributed to the reduced CF transmembrane conductance regulator (CFTR) function as a similar increased retention/uptake was observed in cells whose CFTR expression was downregulated by antisense oligonucleotide. NPs alone did not induce pro-inflammatory cytokine release or cell death. The cell culture system was sensitive to ozone but exposure to the uncoated synthetic NPs used in this study, did not cause any synergistic or suppressive effects. LSM imaging and subsequent image restoration further indicated particle uptake and intracellular localization. Exposure to ozone increased nuclear uptake in both non-CF and CF cells.
  
  
  CONCLUSIONS
  Our findings demonstrate the uptake of NPs using ALI cultures of non-CF and CF airway epithelial cells. The NPs used here were useful in demonstrating uptake by airway epithelial cells without causing adverse effects in presence or absence of ozone. However, to totally exclude toxic effects, chronic studies under in vivo conditions using coated particulates are required.
authors: Department of Pediatrics, National Jewish Health, 1400 Jackson Street, Denver, CO 80206, USA. ahmads@njhealth.org
authors: Shama
authors: S
authors: Ahmad
authors: David O
authors: DO
authors: Raemy
authors: Joan E
authors: JE
authors: Loader
authors: Jenai M
authors: JM
authors: Kailey
authors: Keith B
authors: KB
authors: Neeves
authors: Carl W
authors: CW
authors: White
authors: Aftab
authors: A
authors: Ahmad
authors: Peter
authors: P
authors: Gehr
authors: Barbara M
authors: BM
authors: Rothen-Rutishauser
mesh_terms: D001980:Bronchi / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D003550:Cystic Fibrosis / Q000378:metabolism*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000502:physiology; D016207:Cytokines / Q000096:biosynthesis; D017097:Electric Impedance; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000633:toxicity; D010126:Ozone / Q000633:toxicity*
chemical_list: C505032:CFTR protein, human; D016207:Cytokines; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D010126:Ozone