Thus , the requirement for CD28 in IL-2 promoter activation appears to be due to RE/AP and not the NFAT or AP-1 sites .
thus , the requirement for cd28 in il-2 promoter activation appears to be due to re/ap and not the nfat or ap-1 sites .
O O O O O B-protein_molecule O B-protein_molecule O O O O O O O B-protein_molecule O O O O O O O O