Establishment and characterization of a colonic epithelial cell line MCE301 from transgenic mice harboring temperature-sensitive simian virus 40 large T-antigen gene

We produced an immortalized colonic epithelial cell line, MCE301, using fet al mice transgenic for the temperature-sensitive simian virus 40 large T-an tigen gene. MCE301 cells showed epithelial-like morphology and maintained t ight connections with neighboring cells. The cells grew at a permissive tem perature (33 degreesC), but the growth of the cells was significantly preve nted at the nonpermissive temperature (39 degreesC). The cells expressed la rge T-antigen at 33 degreesC but not at 39 degreesC. MCE301 cells were not transformed, as judged by the absence of anchorage-independent growth in so ft agar gel and lack of tumor formation in nude mice. Electron microscopic studies showed that the cells formed microvilli-like structures on the cell surface and junctional complexes such as tight junctions and desmosomes be tween the cells. The cells expressed cytosketal (acidic cytokeratins and ac tin), basement membrane (laminin and collagen type IV) and junctional compl ex proteins (ZO-1 and desmoplakin I + II), as judged by specific antibodies . Fetal bovine serum, epidermal growth factor, insulin-like growth factor a nd insulin significantly increased the fell growth at 33 degreesC. Moreover , MCE301 cells expressed colonic mucin Muc2 mRNA as demonstrated by reverse transcriptase-polymerase chain reaction, indicating that the cells origina te from mucus-secreting cells. Alkaline phosphatase, a brush border-associa ted enzyme, was detected in the cells. Sodium butyrate (2 mM), an inducer o f cellular differentiation, markedly elevated alkaline phosphatase activity . Thus, the present mouse colonic epithelial cell line MCE301 possessing th ese unique characteristics should provide a useful in vitro model of coloni c epithelium.