abstract |
The present invention relates to a system comprising a modified bacterial gene for cytosine deaminase that has been engineered into a eukaryotic expression vector and the expression of the gene by mammalian cells. The present invention further relates to methods, gene therapies and vaccines that employ the negative selectable marker, cytosine deaminase, which has the ability to produce a toxic antimetabolite 5-fluorouracil from 5-fluorocytosine. |