To analyze antigen-specific T cell activation, we adoptively transferred 5x104 naïve OT-I CD8+ T cells from C57BL/6 into B6.SJL mice 24 hours prior to infection with L. monocytogenes ΔactA/ΔinlB Ova or L. monocytogenes ΔactA/ΔinlB L.p.FlaA Ova with and without RB6-8C5 mAb pre-treatment. The gene discussed is CD8A; the disease is infection.