Regional Differences in Mucociliary Clearance in the Upper and Lower Airways

• DOI: 10.3389/fphys.2022.842592
• Publication Date: 2022-03-09T11:23:17Z
• Authors: Troy D. Rogers; Brian Button; Samir N. P. Kelada; Lawrence E. Ostro...; Alessandra Livrag...; Mark I. Gutay; Charles R. Esther; Barbara R. Grubb
• Keywords: Mucociliary clearance; Submucosal glands

As the nasal cavity is portal of entry for inspired air in mammals, this region exposed to highest concentration inhaled particulate matter and pathogens, which must be removed keep lower airways sterile. Thus, one might expect vigorous removal these substances via mucociliary clearance (MCC) region. We have investigated rate MCC murine compared more distal (trachea). The (posterior nasopharynx, PNP) was ∼3–4× greater than on tracheal wall. This appeared due a abundant population ciliated cells (∼80%) sparsely trachea (∼40%). Interestingly, ventral wall exhibited significantly posterior membrane. trachealis muscle underlying epithelium membrane control surface architecture likely part In our mouse models ( Bpifb1 KO) exhibiting 3-fold increase MUC5B protein lavage fluid, particle transport walls severely compromised, yet normal occurred While blanket mucus covered both PNP trachea, transported as by only PNP. contrast, particles discrete patches or streams trachea. addition, fairly linear, contrast often followed non-linear route. thick, viscoelastic that PNP, ∼10-fold mass did covering could over large areas completely devoid (made breach epithelial layer). not even small thick aids non-ciliated olfactory contributes humidification efficient trapping upper airway