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

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.