Stat6 does not synergize with other signals to activate the IL-4 promoter. Methods were similar to those described in Fig 3, except that cells were also stimulated with calcium ionophore (▧), PMA (▪), both (░), or no agonists (□) with or without IL-4 as indicated. In the presence of IL-4, reporter activity was consistently decreased in Stat6-cotransfected cells for each condition examined. Note that the combination of PMA and IL-4 almost completely repressed the promoter. Results are from one experiment performed in duplicate and are representative of three.