title: Inhalation of ultrafine carbon particles triggers biphasic pro-inflammatory response in the mouse lung.
abstract: High levels of particulate matter in ambient air are associated with increased respiratory and cardiovascular health problems. It has been hypothesised that it is the ultrafine particle fraction (diameter <100 nm) that is largely responsible for these effects. To evaluate the associated mechanisms on a molecular level, the current authors applied an expression profiling approach. Healthy mice were exposed to either ultrafine carbon particles (UFCPs; mass concentration 380 microg x m(-3)) or filtered air for 4 and 24 h. Histology of the lungs did not indicate any pathomorphological changes after inhalation. Examination of the bronchoalveolar lavage fluid revealed a small increase in polymorphonuclear cell number (ranging 0.6-1%) after UFCP inhalation, compared with clean air controls, suggesting a minor inflammatory response. However, DNA microarray profile analysis revealed a clearly biphasic response to particle exposure. After 4 h of inhalation, mainly heat shock proteins were induced, whereas after 24 h, different immunomodulatory proteins (osteopontin, galectin-3 and lipocalin-2) were upregulated in alveolar macrophages and septal cells. In conclusion, these data indicate that inhalation of ultrafine carbon particles triggers a biphasic pro-inflammatory process in the lung, involving the activation of macrophages and the upregulation of immunomodulatory proteins.
authors.affiliation: Ludwig-Maximilians-University, Institute for Epidemiology, Germany.
authors.forename: E
authors.initials: E
authors.lastname: André
authors.forename: T
authors.initials: T
authors.lastname: Stoeger
authors.forename: S
authors.initials: S
authors.lastname: Takenaka
authors.forename: M
authors.initials: M
authors.lastname: Bahnweg
authors.forename: B
authors.initials: B
authors.lastname: Ritter
authors.forename: E
authors.initials: E
authors.lastname: Karg
authors.forename: B
authors.initials: B
authors.lastname: Lentner
authors.forename: C
authors.initials: C
authors.lastname: Reinhard
authors.forename: H
authors.initials: H
authors.lastname: Schulz
authors.forename: M
authors.initials: M
authors.lastname: Wjst
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects; D000818:Animals; D002244:Carbon / Q000008:administration & dosage / Q000633:toxicity; D005260:Female; D019570:Inhalation Exposure / Q000009:adverse effects; D016676:Macrophages, Alveolar / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D010316:Particle Size; D011014:Pneumonia / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D000393:Air Pollutants; D002244:Carbon