To activate primary T cells, lymph nodes were removed and disaggregated. Cells were cultured in RPMI 1640 containing L-glutamine, 10% FBS, 50 μM β-mercaptoethanol and penicillin/streptomycin. Cells were stimulated with 1 μg/ml of the CD3 monoclonal antibody (2C11) and 2 μg/ml anti-CD28 (37.51) in the presence of cytokines IL12 (10 ng/ml) and 20 ng/ml IL2 (20 ng/ml). Cells were stimulated for 24 hours. Live TCR activated CD4+ cells were sorted for CD4+ and CD45.1+ expression and DAP1 exclusion prior to collection for proteomics processing. Mice were “wild-type” (ie non-TCR transgenic) from OT-2 CD45.1 expressing C57bl6 background maintained in-house line.