FIG. 3.

Analysis of ϕC31 integrase plasmid DNA retention within mouse liver. ϕC31 integrase expression plasmid pCSI-HA was hydrodynamically injected into the tail vein of mice. At various points over a time course, the mice were killed, their livers were removed, and total DNA was isolated. (A) Southern blot analysis using a probe to the ϕC31 integrase gene showed an increase in signal over the first 8 hr postinjection, followed by a decrease, and a loss of signal by 48 hr. Below each lane of the blot is the percentage of total ϕC31 integrase plasmid present, as quantified by densitometry. (B) Total DNA transformed into bacterial cells showed an increase in colony number over the first 8 hr after injection, followed by a decrease, until few colonies were detected after day 7. (C) PCR detected the presence of the ϕC31 integrase gene over the 180-day time course.