Nrf2^−/−donor T cells display intact proliferation, activation, and apoptosis during the early phase of alloreactivity. Lethally irradiated BALB/c recipients received 5 × 10⁶ CFSE-labeled B6 WT or Nrf2^−/− T cells. Recipient spleens were analyzed by flow cytometry for CFSE dilution at the indicated time points. (A) Concatenated CFSE line graphs showing the percentages of CFSE^low WT and Nrf2^−/− donor T cells, gated on H-2K^b+ events. (B) Proliferation and division indices of WT and Nrf2^−/− donor T cells. (C) Total numbers of CFSE^low WT and Nrf2^−/− donor T cells. (D) Representative flow cytometric analysis showing upregulation of the activation marker CD25 in the CFSE^low population on WT donor T cells. Expression of activation markers at 96 hours (E) and apoptotic marker (F) on WT and Nrf2^−/− donor T cells, gated on H2-K^b+CFSE^low populations. Data represent the mean + standard deviation combined from 2 or 3 independent experiments (n ≥ 10 per group). *P < .05, **P < .01, ****P < .0001.