Cellular and molecular characteristics of basal cells in airway epithelium

Basal cells exist as a separate layer of cells covering most of the airway basal lamina. In this central position, they can interact with columnar epi thelium, neurons, basement membrane , and the underlying mesenchymal cells. In addition, they interact with inflammatory cells, lymphocytes and dendri tic cells. These interactions take place in the lateral intercellular space between basal cells. In this central position basal cells become a very im portant part of the epithelial-mesenchymal trophic unit of layer airways. I n this review it is shown that basal cells may function as progenitor cells of airway epithelium and have a role in the attachment of columnar epithel ium with the basement membrane. They also have the potential to function in regulation of neurogenic inflammation, the inflammatory response, transepi thelial water movement, oxident defense of the tissue and formation of the lateral intercellular space. Other characteristics of basal cells were not clearly associated with a particular function. The functions for basal cell s listed attempt to explain the presence of recently identified molecules i n basal cells of airway epithelium. It should be pointed out that specific studies have not been carried out which test the relationship between the m olecular function we describe in this review and the basal cell in airway e pithelium.