Evaluation of mouse laryngeal inflammation upon low and high dose cigarette smoke exposures via NanoString analysis

Cigarette smoking is a major risk factor for laryngeal diseases. Despite well-documented cigarette smoke (CS) induced laryngeal histopathological changes in animal models and humans, the underlying immunopathological mechanisms remain largely unexplored. The goal of this study was to evaluate inflammatory and immune cell responses in a CS-exposed larynx. Specifically, we investigated these responses in the mouse larynx after a 4-week subacute low (LD) and high-dose (HD) whole-body mainstream CS exposure. Adult C57BL/6 male mice were assigned to air-exposed control ( n = 10) , low dose (LD; n = 12) and high dose (HD; n = 12) cigarette smoke (CS) exposure groups. LD and HD mice were exposed 1h/day and 4h/day to CS respectively for a total of 4 weeks, M-F only. Laryngeal tissues were harvested 24h after the final exposure, for mRNA expression using a NanoString inflammation panel ( n = 6) and neutrophil/macrophage/T-cell immunohistochemistry (IHC) (n = 6). Out of the 6 samples assigned for NanoString analyses, only 4 per group had stable RIN values and these were subjected to NanoString analysis.