Figure 4.

Gβγ inhibition decreases levels of mRNA encoding STAT4-regulated genes in TCR-stimulated CD4⁺ TH1 cells. Gallein, but not fluorescein, and Gβ₁ siRNA significantly decreased mRNA levels of IL-18Rβ (A), MAP3K8 (B), and LAG-3 (C) in TCR-stimulated naïve and memory TH1 cells. (D) Gallein, but not fluorescein, significantly decreased NKG7 mRNA levels in TCR-stimulated memory TH1 cells. Gallein significantly decreased NKG7 mRNA levels in naïve cells, but fluorescein also caused a significant, but smaller decrease. Gβ₁ siRNA significantly decreased NKG7 mRNA levels in both naïve and memory cells. (E) Gallein, but not fluorescein, significantly decreased OSM mRNA levels in TCR-stimulated naïve TH1 cells. Gallein decreased OSM mRNA levels significantly in memory cells relative to fluorescein-treated cells, but not to control cells. Gβ₁ siRNA significantly decreased OSM mRNA levels in both naïve and memory cells. (A-E) First two sets of graphs: box plots (top) and difference plots (bottom) show data from naïve (left) and memory (right) CD4⁺ T cells isolated from the peripheral blood of 20 healthy donors, stimulated with plate-bound anti-CD3 and soluble anti-CD28, and grown in conditions promoting TH1 differentiation in the absence or presence of gallein or fluorescein for three days. Second two sets of graphs: box plots (top) and difference plots (bottom) show data from primary human naïve (left) and memory (right) CD4⁺ T cells isolated from the blood of 30 healthy donors and stimulated for three days with plate-bound anti-CD3 and soluble anti-CD28 in conditions promoting TH1 differentiation in the presence of Gβ₁ siRNA or NT siRNA. mRNA levels were determined by qPCR. ^*, p < 0.05; ^**, p < 0.01; ^***, p < 0.001; ^****, p < 0.0001.