Transcriptional responses of wild-type and Gcn2-/- Th17 cells to halofuginone and rapamycin

This study was designed to evaluate similarities and differences between transcriptional responses of developing Th17 cells to the prolyl-tRNA synthetase inhibitor, halofuginone, and the mTOR inhibitor, rapamycin. Further comparisons between wild-type and Gcn2-/- Th17 cells allow for investigation into which gene modules regulated by halofuginone or rapamycin treatment require Gcn2. Murine CD4+ CD25- T cells were magnetically isolated from wild-type or Gcn2-/- T cells. These cells were activated through anti-CD3/ anti-CD28 antibodies and polarized into Th17 cells using TGFb plus IL-6. 10 nM halofuginone, 10 nM rapamycin, or vehicle control (DMSO) were added to cultures at the time of activation. Cells were harvested at 4, 18, or 72 hours post-activation and differentiation. RNA was isolated from each sample and used for microarray analysis. Each culture condition and time-point was repeated twice in independent experiments using cells isolated from different wild-type or Gcn2-/- mice. Vehicle versus halofuginone, vehicle versus rapamycin, halofuginone versus rapamycin. Gcn2-/- versus wild-type T cells treated with vehicle, halofuginone, or rapamycin.