Amount of adenovirus genome DNA in the liver after intravenous administration of the AdGRE.mTPO vector. Following administration of AdGRE.mTPO (5 × 10⁸ pfu), dexamethasone (Dex) was administered intraperitoneally (50 μg/dose) on 3 consecutive days starting at days 1, 22, and 43. Following 10 minutes and 1, 4, 22, and 64 days after vector administration, the liver was removed, and the amount of vector genome determined by Southern analysis and quantified by phosphorimager. Data are presented as relative percent of data at 10 minutes on day 0 (defined as 100%). Shown are data for adenovirus genome with dexamethasone (•) and without dexamethasone (○). The data are presented as mean ± SE of three independent experiments.