Damping of luciferase expression from a plasmid DNA vaccine construct does not require beta-2-microglobulin or CD8⁺ T cells. (A) Luciferase expression in vaccinated wild-type and beta-2-microglobin knockout (β2m KO) mice. Wild-type and β2m KO mice were inoculated with plasmid DNA-Luc (n = 4), and luciferase expression in vivo was measured by IVIS imaging. (B) Luciferase expression in vaccinated wild-type and CD8⁺ T-cell-depleted mice. CD8⁺ T cells were depleted by administration of anti-CD8 antibody 3 days before and every third day after plasmid DNA-Luc inoculation for a 28-day period, and in vivo luciferase expression was measured. The line graphs represent mean values; error bars represent SEM.