TYPE-II EPITHELIAL-CELLS OF LUNG .4. ADAPTATION AND BEHAVIOR OF ISOLATED TYPE-II CELLS IN CULTURE

Abstract

Type II lung epithelial cells were isolated from rabbit lungs using the method of Kikkawa and Yoneda. Successful primary cultures were obtained only after utilizing high density cell plating (> 3 .times. 105 viable cells/cm2) and allowing an attachment time of 48 h. Attachment efficiency of the isolated cell preparations was highest when medium was supplemented with 10% fetal calf serum. Consistently successful primary type II lung cell cultures were obtained. Cultures were monitored for a period of 2 wk after initiation. Light, phase and electron microscopy examination demonstrated that these primary cultures were indeed type II cells. The principal morphologic feature was the presence of dense lamellar granules in these cells. These primary cultures retained the characteristic type II features for 3-5 days in vitro, after which cultures exhibited a progressive deterioration and loss of their phenotypic properties. This behavioral pattern of type II cells in culture may represent accelerated proliferation and accelerated transformation of these cells into type I epithelial cells.