Figure 2.

Assessment of UGT1A1 Activity, Measured as Bilirubin Conjugation by AAV8-hUGT1A1-Transduced Huh7 Cells

(A) Conjugated bilirubin (CB) concentration measured in medium after incubating Huh7 cells for 1, 4, or 24 h with 10 μM unconjugated bilirubin (UCB) at time point 72 h post-transduction. Linear regression analysis shows excellent R² of 0.99 up to 3.8 × 10⁴ vg/seeded cell in both 4 and 24 h of incubation (solid lines). Linearity decreases with higher doses to poor R² of 0.94 in 24-h incubation and a moderate R² of 0.96 in 4-h incubation (dotted lines). (B) Comparison of conjugated bilirubin (CB) concentration in medium after 4-h incubation with 10 μM UCB at time point 48 or 72 h after transduction of Huh7 with 3.8 × 10⁴ vg/seeded cell.