Disease activity in mice with experimental colitis given adenoviral IL-10 gene. Disease activity in mice in which experimental colitis was induced by feeding 3% DSS was significantly attenuated at days 7–10 when adenoviral administration of IL-10 was given on day 6. Disease activity in control mice continued at the same level as the adeno-null mice on DSS. Disease activity was slightly higher in adeno-null mice which was significant at day 8, suggesting that adenoviral infection produces some inflammation. This is important to note since Ad-IL-10 still promotes protection despite the tendency towards higher inflammation.