TY - JOUR T1 - Immune modulation by chronic exposure to waterpipe smoke and immediate-early gene regulation in murine lungs JF - Tobacco Control JO - Tob Control SP - s80 LP - s89 DO - 10.1136/tobaccocontrol-2019-054965 VL - 29 IS - Suppl 2 AU - Hermes Reyes-Caballero AU - Bongsoo Park AU - Jeffrey Loube AU - Ian Sanchez AU - Vinesh Vinayachandran AU - Youngshim Choi AU - Juhyung Woo AU - Justin Edwards AU - Marielle C Brinkman AU - Thomas Sussan AU - Wayne Mitzner AU - Shyam Biswal Y1 - 2020/02/01 UR - http://tobaccocontrol.bmj.com/content/29/Suppl_2/s80.abstract N2 - Objective We investigated the effects of chronic waterpipe (WP) smoke on pulmonary function and immune response in a murine model using a research-grade WP and the effects of acute exposure on the regulation of immediate-early genes (IEGs).Methods WP smoke was generated using three WP smoke puffing regimens based on the Beirut regimen. WP smoke samples generated under these puffing regimens were quantified for nicotine concentration. Mice were chronically exposed for 6 months followed by assessment of pulmonary function and airway inflammation. Transcriptomic analysis using RNAseq was conducted after acute exposure to characterise the IEG response. These biomarkers were then compared with those generated after exposure to dry smoke (without water added to the WP bowl).Results We determined that nicotine composition in WP smoke ranged from 0.4 to 2.5 mg per puffing session. The lung immune response was sensitive to the incremental severity of chronic exposure, with modest decreases in airway inflammatory cells and chemokine levels compared with air-exposed controls. Pulmonary function was unmodified by chronic WP exposure. Acute WP exposure was found to activate the immune response and identified known and novel IEG as potential biomarkers of WP exposure.Conclusion Chronic exposure to WP smoke leads to immune suppression without significant changes to pulmonary function. Transcriptomic analysis of the lung after acute exposure to WP smoke showed activation of the immune response and revealed IEGs that are common to WP and dry smoke, as well as pools of IEGs unique to each exposure, identifying potential biomarkers specific to WP exposure. ER -