Biological Characterization of Gastric Surface Mucous Cell Line GSM06 from Transgenic Mice Harboring Temperature-Sensitive Simian Virus 40 Large T-Antigen Gene

Abstract

We investigated the biological features of gastric surface mucous cell line GSM06, established from transgenic mice harboring the temperature-sensitive simian virus 40 large T-antigen gene. GSM06 cells grew until confluent monolayers were formed at the permissive temperature (33 °C), showing that the cessation of cell growth may be due to contact inhibition. Moreover, the cells did not grow in a soft agar gel. However, chromosome numbers of the cells were not normal. When GSM06 cells were cultured in Daigo’s T medium supplemented with growth factors and 10% fetal bovine serum at 33°C for 1, 3 or 9 days, the cells gradually grew to confluent monolayers (day 9). Morphological observations revealed that the cells time-dependently formed microvil-li-like structures and yielded periodic acid-Schiff-positive glycoproteins on the cell surface with the growth of the structures. When GSM06 cells were cultured on a membrane filter for 1-9 days, elevated transepithelial resistance was noted in a culture period-dependent fashion. On day 9, junctional complexes such as tight junctions and desmosomes were observed between the cells. In addition, prostaglandin E₂ production was evoked from the cells from day 1. In order to determine cell viability, GSM06 cells were labeled with the fluorescence dye 2´7´-bis(carboxyethyl)-carboxyfluorescein. Exposure of GSM06 cells to ethanol (7.5-17.5%) elicited cell injuries in a concentration-related manner on day 1 whereas these cytotoxic effects were attenuated on days 3 and 9, suggesting that this protection may be, at least in part, related to the increased glycoproteins and transepithelial resistance. GSM06 cells possessing these unique characteristics should be highly useful as an in vitro model of gastric epithelium.

Development and Characterization of Conditionally Immortalized Gastric Epithelial Cell Lines from Transgenic Rats Harboring Temperature-Sensitive Simian Virus 40 Large T-antigen Gene.

“…Moreover, RGE1-22 cells produced PGE 2 . These gastric epithelial characteristics of the cells were comparable to those of GSM06 cells (Sugiyama et al, 1993;Tabuchi et al, 1996). In all cells established here, nonpermissive temperature decreased expression level of large T-antigen and arrested cell growth.…”

“…When the cells were cultured on a cell culture insert at 33°C, TER was detected in RGE1-01, RGE1-02, RGE1-03, RGE1-21, RGE1-22 and RGE2-01 cells, with levels of the 137, 6.1, 47.1, 85.7, 58.6 and 34.3 Ω/cm 2 , respectively. The level of TER of RGE1-01 was comparable to that of canine kidney MDCK (TER = 100 Ω/cm 2 ) (Cereijido et al, 1980) and porcine kidney LLC-PK1 cells (170 Ω/cm 2 ) cells (Hull et al, 1976), and was smaller than that of GSM06 cells (790 Ω/cm 2 ) (Tabuchi et al, 1996). On the other hand, nonpermissive temperature markedly decreased the TER in five cells (Fig.…”

“…1 and 2). In the same way, GSM06 cells showed differentiated characteristics such as production of mucous layer on the cell surface and transforming growth factor α at the nonpermissive temperature (Konda et al, 1997;Sugiyama et al, 1993;Tabuchi et al, 1996). Thus, these cell lines in addition to GSM06 cells should be valuable tools with which to study the regulation of differentiation of gastric epithelial cells.…”

“…TER between the apical and basolateral sides was measured using a Millicell electrical resistance system (Millipore Co., Bedford, MA, USA) as described previously (Tabuchi et al, 1996).…”

Gastrin stimulates the growth of gastric pit cell precursors by inducing its own receptors

“…Morphologically, GSM06 cells are rounded or polyhedral, as is typical of primary cultured gastric surface mucous cells (3,8,24,42). Electron microscopy revealed that the cells contain a small number of secretory granules (20,38). Immunologic studies indicate that the GSM06 cells are positive for PAS and class I concanavalin A but negative for H,K-ATPase and class III concanavalin A (37).…”