Fig. 3. Repression of cytokine genes by GCs in T lymphocytes does not require the DNA-binding function of GR. Primary thymocytes of either wild-type (GR^+/+) or GR^dim genotype were cultured in the absence (con) or presence of 10^–6 M dexamethasone and 10 µg/ml PMA/0.5 µg/ml ionomycin (P/I) for 6 h. (A and C) IL-2 and IFN-γ mRNA levels were determined by RNase protection analysis and normalized to TATA box-binding protein (TBP). (B and D) Quantitative evaluation of the data shown in (A) and (C). The level after induction by P/I was taken as 100%. (E) IL-2 analysis of primary CD4⁺ splenocytes by RNase protection using CytOX RNA for normalization. Cells were cultured on αCD3-coated culture dishes in the absence or presence of 10^–6 M dexamethasone for 4 h.