Epithelial cells from human sinonasal mucosa were cultured using an air-liquid interface culture model producing a well-differentiated phenotype. Specimens were characterized as chronic rhinosinusitis with (CRSwNP) or without (CRSsNP) nasal polyps and healthy control mucosa. Culture wells were exposed to HDM, diesel exhaust particles (DPM), or a combination (HDM + DPM) over 24 hours, and responses in the three groups were compared. CBF and TEER were measured to assess mucociliary and barrier function, respectively. Interleukin-6 (IL-6) and 33 (IL-33) were measured after 24 hours. Results following challenge testing are expressed as fold changes from baseline.

Baseline CBF was lower in CRSsNP compared with control. HDM significantly reduced CBF and TEER in the CRSwNP group compared with its vehicle. In CRSwNP and CRSsNP, HDM induced an increase in IL-6 compared with its car. Results are expressed as median and in IL-33 in CRswNP. Exposure to DPM did not affect CBF, TEER, and cytokine release in all groups.

The study concluded that CRSwNP and CRSsNP cells exhibit altered responses, particularly to HDM, even after being removed from their host and cultured in vitro, suggesting an intrinsic cell dysfunction of the upper airway epithelium.

Reference: https://journals.sagepub.com/doi/full/10.1177/1945892419853103