A. Quaroni et Jf. Beaulieu, CELL-DYNAMICS AND DIFFERENTIATION OF CONDITIONALLY IMMORTALIZED HUMANINTESTINAL EPITHELIAL-CELLS, Gastroenterology, 113(4), 1997, pp. 1198-1213
Background & Aims: Intestinal epithelial cell lines capable of differe
ntiating in monolayer culture have been difficult to obtain, prompting
the use of novel approaches including immortalization with oncogenes
or tumor viruses, The aim of this study was to obtain conditionally im
mortalized human intestinal epithelial cells (temperature-sensitive fe
tal human intestinal [tsFHI] cells) and study their growth and differe
ntiation capabilities. Methods: Intestinal cells from human fetuses we
re transformed with a temperature-sensitive simian virus 40 large tumo
r antigen, cloned, and screened for expression of intestinal markers.
Results: Establishment of tsFHI cells was crucially dependent on a gro
wth medium based on OptiMEM. At 32 degrees C, the tsFHI cells prolifer
ate and display crypt cell markers, Only a few scattered differentiate
d cells are observed together with cells displaying the morphological
signs of apoptosis, A shift to 39 degrees C results in irreversible gr
owth arrest and acquisition of an enterocyte-like phenotype. Expressio
n of the cyclin-dependent kinase inhibitor p21/WAF1/Cip1 is induced wi
thin hours of a shift to 39 degrees C 1-2 days before corresponding in
creases in brush border enzymes, suggesting a role in the induction ra
ther than in the maintenance of a differentiated phenotype. Conclusion
s: The tsFHI cells recapitulate key aspects of intestinal cell dynamic
s in vitro and seem particularly suited for the study of early events
in cell differentiation.