Although AHS is not observed in B*57:01-Tg mice, ABC treatment increases the proportion of cytokine- and cytolytic granule-secreting effector memory CD8+ T cells in CD4+ T cell-depleted B*57:01-Tg/PD-1−/− mice, thereby inducing skin toxicity with CD8+ T cell infiltration, mimicking AHS. This evidence concerns the gene PDCD1 and mitochondrial DNA depletion syndrome 4a.