Figure 1.

Adenoviral vector encoding murine interleukin 10 (AdvmuIL-10) induced bioactive IL-10 release from epithelial cells in vitro. HT29 and SW620 cells were plated at 1×10⁶ /ml in a 12 well plate and infected with AdvmuIL-10 or empty cassette adenoviral vector (Adv0, MOI 50:1). Supernatants were sampled at 36 hours and daily thereafter. Cultures were passaged 1:2 every week. No IL-10 was detected in Adv0 infected epithelial cells. (A) IL-10 release from AdvmuIL-10 infected cells. (B) RAW cells (2×10⁵) were plated onto a 96 well plate and incubated with IL-10 10 ng/ml, dilutions of the supernatant (Sup) from AdvmuIL-10 infected HT29 cells, or supernatant that had been preincubated with 10 μg/ml (final) antimurine IL-10 antibody for one hour. Cells were cultured for 24 hours with or without 10 ng/ml lipopolysaccharide (LPS). Supernatants were harvested and assayed for tumour necrosis factor α (TNF-α) release by ELISA. Results are expressed as a percentage of the LPS induced TNF-α response (mean of three experiments). Identical results were obtained using supernatants from SW620 cells.