Establishment of immortal swine kidney epithelial cells.
Using normal swine kidney epithelial (SKE) cells that were shown to be senescent at passages 12 to 14, we have established one lifespan-extended cell line and two lifespan-extended cell lines by exogenous introduction of the human catalytic subunit of telomerase (hTERT) and simian virus 40 large T-antigen (SV40LT), all of which maintain epithelial morphology and express cytokeratin, a marker of epithelial cells. SV40LT- and hTERT-transduced immortal cell lines appeared to be smaller and exhibited more uniform morphology relative to primary and spontaneously immortalized SKE cells. We determined the in vitro lifespan of primary SKE cells using a standard 3T6 protocol. There were two steps of the proliferation barrier at 12 and 20, in which a majority of primary SKE cells appeared enlarged, flattened, vacuolated, and ss-galactosidase-positive, all phenotypical characteristics of senescent cells. Lifespan-extended SKE cells were eventually established from most of the cellular foci, which is indicative of spontaneous cellular conversion at passage 23. Beyond passage 25, the rate of population doubling of the established cells gradually increased. At passage 30, immortal cell lines grew faster than primary counterpart cells in 10% FBS-DMEM culture conditions, and only SV40LT-transduced immortal cells grew faster than primary and other SKE immortal cells in 0.5% FBS-DMEM. These lifespan-extended SKE cell lines failed to grow in an anchorage-independent manner in soft-agar dishes. Hence, three immortalized swine kidney epithelial cells that are not transformed would be valuable biological tools for virus propagation and basic kidney epithelial cell research.
Kwak
Sungwook
S
Laboratory of Cell Growth and Function Regulation, Division of Bioscience and Technology, College of Life and Environmental Sciences, Korea University, Seoul, Korea.
Jung
Ji-Eun
JE
Jin
Xun
X
Kim
Sun-Myung
SM
Kim
Tae-Kyung
TK
Lee
Joong-Seob
JS
Lee
Soo-Yeon
SY
Pian
Xumin
X
You
Seungkwon
S
Kim
Hyunggee
H
Choi
Yun-Jaie
YJ
D000818:Animals; D018929:Cell Culture Techniques; D002461:Cell Line, Transformed; D004268:DNA-Binding Proteins / Q000235:genetics; D004847:Epithelial Cells / Q000166:cytology* / Q000201:enzymology; D007668:Kidney / Q000166:cytology* / Q000201:enzymology; D013539:Simian virus 40 / Q000235:genetics; D013552:Swine; D019098:Telomerase / Q000235:genetics; D014170:Transformation, Genetic
D004268:DNA-Binding Proteins; D019098:Telomerase