title: Release of inflammatory cytokines, cell toxicity and apoptosis in epithelial lung cells after exposure to ambient air particles of different size fractions.
abstract: Several studies have shown that particles of smaller size may be more potent than larger to induce inflammatory and toxic responses in cultured lung cells. However, the relative importance of different size fractions of ambient PM to induce such effects is still not known. In this study, we investigated the potency of different size fractions of urban ambient air particles to induce release of inflammatory cytokines in the human alveolar cell line A549 and primary rat type 2 cells. A mineral-rich ambient air PM10 sample collected in a road tunnel (road PM10) was also included. The coarse fraction of the urban ambient air particles demonstrated a similar or higher potency to induce release of the proinflammatory cytokines IL-8/MIP-2 and IL-6 compared to the fine and ultrafine fractions. The coarse fraction was also the most toxic in both cell systems. In contrast to the A549 cells, no induction of cytokine release was induced by the ultrafine particles in the primary type 2 cells. The mineral-rich road PM10 may be equally or more potent than the various size fractions of the ambient air particles to induce cytokines in both cell types. In conclusion, the coarse fraction of ambient particles may be at least as potent by mass as smaller fractions to induce inflammatory and toxic effects in lung cells.
authors.affiliation: Division of Environmental Medicine, Norwegian Institute of Public Health, PO Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: R B
authors.initials: RB
authors.lastname: Hetland
authors.forename: F R
authors.initials: FR
authors.lastname: Cassee
authors.forename: M
authors.initials: M
authors.lastname: Refsnes
authors.forename: P E
authors.initials: PE
authors.lastname: Schwarze
authors.forename: M
authors.initials: M
authors.lastname: Låg
authors.forename: A J F
authors.initials: AJ
authors.lastname: Boere
authors.forename: E
authors.initials: E
authors.lastname: Dybing
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000633:toxicity*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis*; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology*; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis; D016209:Interleukin-8 / Q000096:biosynthesis; D008168:Lung / Q000473:pathology*; D008297:Male; D008903:Minerals / Q000032:analysis / Q000633:toxicity; D010316:Particle Size; D051381:Rats; D011921:Rats, Inbred WKY
chemical_list: D000393:Air Pollutants; D016207:Cytokines; D015850:Interleukin-6; D016209:Interleukin-8; D008903:Minerals