| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2596769 | Toxicology | 2009 | 10 Pages |
Immunomodulatory effects of chemicals adsorbed to particles with aerodynamic diameter below 0.49 μm (PM0.5) collected in winter 2001 at three sampling points (industrial area [LPIn], traffic-influenced urban area [LPCi], and control area [LPCo]) of La Plata, Argentina, were investigated. The sampling of particulate matter was carried out with high-volume collectors using cascade impactors. PM0.5-adsorbed compounds were hexane-extracted by accelerated solvent extraction. For immunological investigations, human peripheral blood lymphocytes were activated by phytohemagglutinin and exposed to dimethyl-sulfoxide dilutions of PM0.5-extracts for 24 h. Vitality/proliferation was quantified using MTT, released interferon-γ (IFN-γ) and interleukin-4 (IL-4) by ELISA. Cytokine production but not vitality/proliferation was significantly suppressed by all of the highest extract concentrations. Generally, suppression of IFN-γ by PM0.5-extracts was stronger than those of IL-4. Based on administered mass of PM0.5, all extracts suppressed IFN-γ production nearly uniform. Contrary, LPCi-extracts exerted maximum IFN-γ suppression based either on air volume or regarding PM0.5-adsorbed PAH. Also the ranking of PM0.5-associated effects on IL-4 production differs in dependence of the chosen reference points, either mass or [μg/ml] or air volume [m3/ml] related dust quantities in cell culture. Based on the corresponding air volume, LPCi-extracts inhibited IL-4 production to the maximum extend, whereas suppression of IL-4 was comparable based on concentrations. This indicates that not only the disparate PM0.5-masses in air cause varying impacts, but also that disparities in PM0.5-adsorbed chemicals provoke different effects on immune responses and shifts in the regulatory balance that might have implications for allergy and cancer development.
