The site of leukocyte migration through the tracheal mucosa in the guinea pig.
The tracheal mucosa of the guinea pig was examined using light microscopy, thin section, and freeze-fracture replicas with transmission electron microscopy and scanning electron microscopy. These studies demonstrated that inflammatory cells en route to the mucosal surface migrate through the epithelium in file through solitary openings rather than randomly between epithelial cells. The fact that leukocytes migrate through these openings rather than randomly between epithelial cells has important implications. First, it provides a pathway for circulating cells to gain access to the surface of the airway where they can function as the first line of defense against inhaled material. Second, the movement of leukocytes through specified pathways rather than randomly between cells minimizes the number of openings required for cell transit so that fluid and solute movement can be more tightly controlled. Third, the prevention of random migration may also be important in minimizing the contact between the migratory cells and the epithelial sensory nerve net.
D000818:Animals; D002465:Cell Movement; D005260:Female; D005614:Freeze Fracturing; D006168:Guinea Pigs; D007962:Leukocytes / Q000502:physiology*; D008297:Male; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009092:Mucous Membrane / Q000473:pathology* / Q000648:ultrastructure; D014136:Tracheitis / Q000473:pathology*