T cells (0.6×106) were lysed in (35 μl) Carin lysis buffer (20 mM Tris-HCl [pH 8.0], 138 mM NaCl, 10 mM EDTA, 100 mM NaF, 1% Nonidet P-40, 10% glycerol, 2 mM Na vanadate) supplemented with complete protease inhibitors (Roche). Proteins were separated on 10% SDS-polyacrylamide gels and blotted onto PVDF membranes according to standard protocols. The following primary antibodies were used: anti-actin (AC-74; Sigma-Aldrich, St. Louis, MO), mouse anti-Runx3 (2B3; Abcam) and rabbit anti-Th-POK 22 (link). Secondary antibodies were a peroxidase-conjugated AffiniPure goat anti-rabbit IgG (H+L) (Jackson ImmunoResearch Laboratories) and a HRP-conjugated AffiniPure Goat Anti-Mouse IgG (Jackson ImmunoResearch Laboratories). Signals were detected using ECL (SuperSignal West Dura Extended Duration Substrate from ThermoScientific).