The biological effect of particles on respiratory epithelial cells involves, in part, the generation of an oxidative stress and a consequent cascade of reactions culminating in inflammatory mediator release. Whether there is either an immediate, transitory activation or a persistent response of the cells to the particles has not been established.

We tested the postulate that respiratory epithelial cells exposed to wood smoke particle (WSP) would demonstrate increased oxidative stress and mediator release following re-seeding and propagation of the cells for two generations post-initial exposure. BEAS-2B cells grown to confluence (G0) in 75 cm(2) flasks were treated for 18 h with the WSP at 0, 25, 50 and 100 µg/ml. The flasks we...