title: Establishment of murine cell lines by constitutive and conditional immortalization.
abstract: Mouse cell lines were immortalized by introduction of specific immortalizing genes. Embryonic and adult animals and an embryonal stem cell line were used as a source of primary cells. The immortalizing genes were either introduced by DNA transfection or by ecotropic retrovirus transduction. Fibroblasts were obtained by expression of SV40 virus large T antigen (TAg). The properties of the resulting fibroblast cell lines were reproducible, independent of the donor mouse strains employed and the cells showed no transformed properties in vitro and did not form tumors in vivo. Endothelial cell lines were generated by Polyoma virus middle T antigen expression in primary embryonal cells. These cell lines consistently expressed relevant endothelial cell surface markers. Since the expression of the immortalizing genes was expected to strongly influence the cellular characteristics fibroblastoid cells were reversibly immortalized by using a vector that allows conditional expression of the TAg. Under inducing conditions, these cells exhibited properties that were highly similar to the properties of constitutively immortalized cells. In the absence of TAg expression, cell proliferation stops. Cell growth is resumed when TAg expression is restored. Gene expression profiling indicates that TAg influences the expression levels of more than 1000 genes that are involved in diverse cellular processes. The data show that conditionally immortalized cell lines have several advantageous properties over constitutively immortalized cells.
authors: Department of Gene Regulation and Differentiation, German Research Center for Biotechnology, GBF, Mascheroder Weg 1, D-38124 Braunschweig, Germany.
authors: Tobias
authors: T
authors: May
authors: Peter P
authors: PP
authors: Mueller
authors: Herbert
authors: H
authors: Weich
authors: Natali
authors: N
authors: Froese
authors: Urban
authors: U
authors: Deutsch
authors: Dagmar
authors: D
authors: Wirth
authors: Andrea
authors: A
authors: Kröger
authors: Hansjörg
authors: H
authors: Hauser
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology*; D005347:Fibroblasts / Q000166:cytology* / Q000502:physiology*; D005818:Genetic Engineering / Q000379:methods*; D051379:Mice; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins