Expansion of Bronchial Epithelial Cell Populations by In Vitro Culture of Explants from Dysplastic and Histologically Normal Sites

The genetic and phenotypic properties of cells which ultimately give rise to carcinoma of the lung are not well defined in part because of unavailability of preneoplastic cells from well-characterized dysplastic sites. In order to expand bronchial epithelial cell populations from patients at high risk for lung cancer, endobronchial biopsy specimens were explanted onto collagen- and fibronectin-coated dishes and cultured in serum-free, chemically defined media. One hundred forty-nine biopsy pairs were obtained from smokers and from healthy volunteers for culture and histologic evaluation. The histologic appearances of mucosa adjacent to the site of the cultured biopsies ranged from normal through varying degrees of noninvasive squamous dysplasia to invasive carcinoma. Confluent monolayers of pure epithelial cells were obtained from 68% of the cultured explants. Sites exhibiting high-grade dysplasia were 51% more likely to yield successful cultures than sites exhibiting normal histology (13 of 14 cultures s...