Perturbation of gastric mucosa in mice expressing the temperature-sensitive mutant of SV40 large T antigen. Potential for establishment of an immortalised parietal cell line.
Gastric parietal cells have a unique secretory membrane system that undergoes a profound transformation when the parietal cell is stimulated to secrete acid. Understanding this process has been hindered by the lack of an immortalised parietal cell line. Here we have explored a strategy for the development of a parietal cell line by the generation of transgenic mice bearing the temperature-sensitive mutant of the SV40 large T antigen (SV40 tsA58) under the control of the regulatory sequences of the gastric H+/K+ ATPase beta-subunit (H/Kbeta-tsA58). Three H/ Kbeta-tsA58 transgenic mouse lines were established, namely 218, 224 and 228, all of which expressed the tsA58 T antigen in the gastric mucosa. Unexpectedly, the gastric mucosae of all lines were hypertrophic indicating that the temperature-sensitive large T antigen was partially active at 37 degrees C. Immunofluorescence together with light and electron microscopic studies revealed that mature parietal and zymogenic cells were absent in H/Kbeta-tsA58 transgenic lines 218 and 224, and small undifferentiated cells were the dominant cell type in the gastric units. On the other hand, a few mature parietal cells were detected in line 228 together with an increased proportion of undifferentiated cells and, normally rare, pre-parietal cells. As line 228 represented a rich source of pre-parietal cells, gastric cells from line 228 were isolated and cultured at 33 degrees C, the permissive temperature for tsA58. Gastric epithelial cells, expressing the T antigen, were maintained in culture for over 6 weeks. Upon a temperature shift to 39 C the cultured gastric cells developed characteristics of differentiated parietal cells, including the presence of a nascent canaliculus and dramatically increased production of the gastric H+/K+ ATPase beta-subunit. Therefore, this system shows the potential to generate an immature parietal cell line that can be induced to differentiate in vitro.
Stewart
L Ann
LA
Department of Pathology and Immunology, Monash University Medical School, Prahran, Victoria, Australia.
van Driel
Ian R
IR
Gleeson
Paul A
PA
D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000235:genetics / Q000378:metabolism*; D002461:Cell Line, Transformed; D019070:Cell Lineage; D005260:Female; D005753:Gastric Mucosa / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D017506:H(+)-K(+)-Exchanging ATPase / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010295:Parietal Cells, Gastric / Q000166:cytology* / Q000378:metabolism; D021122:Protein Subunits; D012045:Regulatory Sequences, Nucleic Acid; D013696:Temperature
D000952:Antigens, Polyomavirus Transforming; D021122:Protein Subunits; D017506:H(+)-K(+)-Exchanging ATPase