Importantly, the percentage of tumor-infiltrating CD8+ T cells for the ICIE group is the highest (23.8 ± 0.6% out of all T cells) among all groups, with a highest CD8+/Treg ratio of 17.6 ± 10.3 (Fig. 6c) that is 117 times of the CD8+/Treg ratio in the L tumor with the PBS treatment alone. This evidence concerns the gene CD8A and neoplasm.