Fig. 1

Live-cell imaging system for exposure of pHBEC-ALI exposed to woodsmoke produced in real-time. (A) Red oak fragments (500–2000 um) are heated to 550 °C using a ceramic ring heater moving over a quartz tube. Calibration-grade air is supplied through the furnace at a rate of 4 L/min. The resulting woodsmoke is diluted with and carried by an additional 50 L/min flow of calibration-grade air. (B) A flow of 20 mL/min diluted smoke is brought under negative pressure into a 300 mL bottle and mixed with 170 mL/min of humidified air and 10 mL/min (5%) CO₂ before entering a stage-top imaging and exposure chamber holding pHBEC-ALI cultured on a 12-mm Transwell™ insert (C). In the exposure chamber, the intensity of 510 nm fluorescence induced by sequential excitation of pHBEC-ALI expressing Grx1-roGFP2 with 408 nm and 488 nm is monitored at 40X magnification with 60-s resolution. All Teflon and stainless-steel components are heated to prevent condensation