Fig. 1.

Effect of TNF-α on cholesterol efflux. Cells were prelabeled for 24 h with [³H] cholesterol as described in “Experimental Procedures.” After thorough washing to remove unincorporated label, they were incubated with either taurocholate micelles containing 250 µM cholesterol or an LXR agonist T0901317 with or without 100 ng/ml of TNF-α added to both the apical and basolateral medium. ApoA1 was also added to the basolateral medium. Following 18-h incubation, the amount of labeled cholesterol recovered in the basolateral medium was estimated as described in “Experimental Procedures.” Values for each treatment represent a mean ± SE of 6 individual wells of a representative experiment from three separate experiments all showing similar results. *P < 0.05 versus control.