Figure 3. The effect of ApoE on lipoprotein-induced Sp1 DNA-binding activity.

Mouse macrophages were treated with 20 µg/ml of wild-type (E⁺/B), ApoE-free (EÎ/B) or ApoE3-enriched (E3/B) lipoproteins, or culture medium alone (control) for 4 hrs. The amount of Sp1 bound to the ABCA1 promoter region was determined by ChIP analysis, and expressed as the ratio of input controls. Values represent the mean ± SEM of 5 separate experiments. * P<0.05 compared to control, ^† P<0.05 compared to E⁺/B or E3/B lipoprotein treatment.