Furthermore, we observed a marked decrease of PD-1–expressing CD3+ T cells in the peripheral blood (Figure 8D), and CD3+ T cells showed a statistically significant decrease in the proportion of PD-1+ cells in response to IL-15 stimulation and PD-1 blockade in both the spleen and tumor of TIL-PDX-LUAD mice (Figure 8, E and F). The gene discussed is IL15; the disease is neoplasm.