Cytokine profile in BALF 3 and 24 hours after instillation. A) MIP-2 levels are significantly increased after quartz instillation. * P < 0.05 (n = 6 for gold and n = 3 for quartz) B) No significant differences were found in IL-6 levels. A trend towards an increase is seen after instillation of 250 nm single gold particles. C) A trend towards an increase in TNF-α levels was found for 250 nm single gold particles and agglomerated 50 nm particles.