293 cell lines that inducibly express high levels of adenovirus type 5 precursor terminal protein.

293 cell lines that inducibly express high levels of adenovirus type 5 precursor terminal protein (pTP) under the control of a tetracycline-dependent promoter were constructed. To construct the cell lines expressing pTP, 293 cells were stably transfected with a plasmid encoding the tetracycline repressor/VP16 transactivator protein (tTA) using selection with hygromycin. Cell lines that expressed high levels of tTA activity were then stably transfected with plasmids in which pTP expression is directed by the tTA-dependent promoter from either a cDNA or a modified genomic construct using selection with G418. Cell lines that expressed high, inducible levels of pTP efficiently complemented a temperature-sensitive pTP mutant virus for growth and plaque formation at the nonpermissive temperature.