Quantification of proviral DNA in cell lysates of first and second round infected human Hs578T cells during a time-course experiment. Hs578T cells infected with either MMTV(C3H) (A & C) or MMTV(C3H)hp1 (B & D) were cultured in the presence or absence of 10−6 M DEX. Genomic DNA extracted from infected cells at the indicated time points and semi-quantitative PCR performed. -ve: non-transduced Hs578T cells. +ve: producer cells. Equal DNA loading was controlled in the PCR assay with GAPDH-specific primers (bottom panels). Real-time TaqMan PCR was performed for an accurate quantification of proviral loads in infected Hs578T cells (E), during the time-course experiment. Equal loading of the PCR reactions were quantified in a real-time TaqMan PCR specific for the APOB gene.