Quantitative assay for the transforming DNA activity in cell culture products for human use

DNA isolates from a number of established cell lines have been tested for their transforming capacity in the NIH3T3 transformation assay. It has been found that this assay can be used to quantify the amount of transforming DNA at a submicrogram to milligram level. This assay system has been applied to validate the reduction of transforming DNA in various purification steps of cell culture products. The NIH3T3 assay system has been shown useful for in-process control and release of cell culture derived vaccines or therapeutics.