CD45.2+ mice were immunized intramuscularly with 106 or 109 PFU of Ad5-SARS-2 spike, and at day 28, splenic CD8 T cells were MACS-sorted. Subsequently, live, CD8+, CD44+, Kb VL8+ cells were FACS-sorted to ~99% purity, and numbers were normalized for adoptive transfer into CD45.1+ recipient mice. (A) Experimental approach for evaluating secondary expansion of donor CD8 T cells. (B) Representative FACS plots showing the frequencies of donor CD8 T cells after boosting. (C) Summary of donor-derived CD8 T cells in PBMCs. (D) Summary of donor-derived CD8 T cells in spleen. (E) Summary of donor-derived CD8 T cells in draining lymph nodes. Data from panels B-E are from day 14 post-boost. Data are from one experiment with n=5 per group. Experiment was repeated once with similar results. Indicated P values were determined by Mann-Whitney U test.