FIGURE 1.

Higher GRβ:GRα ratio attributes to lower sensitivity to Dex. (A) Treg cells, B-1 cells, and MMΦs all have a higher GR-β/GR-α ratio in mRNA than their immunogenic counterparts. CD3⁺CD4⁺CD25⁺Foxp3-eGFP⁺ Treg cells, CD3⁺CD4⁺CD25⁻ Foxp3-eGFP⁻ Teff cells, CD5⁺CD19⁺CD23⁻FSC^large B-1a cells, CD5⁻CD19⁺CD23⁻FSC^large B-1b cells, CD19⁺CD23⁺ FSC^small B-2 cells, CD11c^loCD40^lo MMΦs, and CD11c^hi DCs were flow sorted from BALB/c Foxp3-eGFP mice. Total RNA was isolated and reverse-transcribed, and qRT-PCR was performed using the GRα- or GRβ-specific primer pair and GAPDH as an internal standard (10). Data are mean ± SD of five experiments. *p ≤ 0.001 (one-way ANOVA). (B) Knockdown (“KD”) of GRα decreases, whereas KD of GRβ increases, Dex-induced depletion of B-1 cells in vivo. B-1 cells were treated ex vivo with siRNAs (10). KD efficiencies were within 58–73% (not shown). The treated cells were adoptively transferred into the peritoneal cavity, followed by an intramuscular injection of dexamethasone (8). Cell depletion from the peritoneal cavity was measured as relative to that of untreated B-1 cells (“Relative sensitivity”). Data are mean ± SD of three experiments. *p ≤ 0.003 (one-way ANOVA).