Pneumologie 2010; 64 - A6
DOI: 10.1055/s-0029-1247903

Impact of 9,10-phenanthrene quinone (PQ) on surface reactivity of ultrafine carbon particles (UfCP): Analysis of defence functions of rat alveolar macrophages

I Beck-Speier 1, F Tian 1, B Oswald 1, KL Maier 1, E Karg 1, W Beisker 2, M Semmler-Behnke 1, S Takenaka 1, T Stöger 1
  • 1Institute for Inhalation Biology
  • 2Institute of Toxicology, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg/Munich

Introduction: Ultrafine ambient particles are involved in pathogenesis of respiratory diseases. Particle surface area and adsorbed organic compounds including quinones may determine particle reactivity towards pulmonary target cells. We hypothesized that coating of UfCP with PQ (PQ-UfPC) changes reactivity towards alveolar macrophages (AM) compared to pristine particles. PQ-UfCP served as model for combustion-derived particles because PQ is a major quinone in diesel exhaust particles and atmospheric particulate matter. Viability, phagocytosis, respiratory burst activity, formation of prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) and the integrity of the actin filament were studied. These parameters were chosen to evaluate the functionality of AM treated with these particles.

Methods: AM of healthy WKY rats were incubated with particles (60min, 37°C) and analysed for viability by WST-1 test, for phagocytosis of fluorescent opsonized zymosan (OZ) by fluorescence and laser scanning microscopy (LSM) and flow cytometry, for respiratory bust activity by measuring chemiluminescence, and for formation of PGE2 and LTB4 by evaluating specific enzyme immunoassays.

Results: Viability was not affected within 1h particle treatment, but after 24h viability of PQ-UfCP-treated AM was strongly reduced (p<0.05). Phagocytosis and respiratory burst activity were significantly reduced by PQ-UfCP-treated AM (p<0.05). Formation of PGE2 and LTB4 was elevated in UfCP-treated (p<0.05) but not in PQ-UfCP-treated AM. Shown by LSM, actin filaments, being mandatory for these processes, were destroyed by uptake of PQ-UfCP in AM.

Conclusion: We conclude that reactivity of particulate surface structure has an impact on AM functions. Coating of pristine UfCP with PQ results in reduced phagocytosis, respiratory burst activity, lipid mediator formation and shrinking of actin filaments, suggesting a diminished defense capacity against infections.