GATA-1 upregulates CCR5 promoter activity through interaction with GATA elements on the promoter. Twenty million PM1 cells were transfected with 10 μg of the indicated CCR5 promoter-luciferase construct along with 10 μg of either pMT2T or pMT-GATA-1, and luciferase assays were performed 40 hours after transfection, as described previously.4 Results are reported as means ± SD from four independent experiments. Similar results were obtained for THP-1 cells (data not shown).