CTLA4 and neoplasm: Although there was no statistically significant difference, flow cytometric analysis also showed that the combination of B. longum 420 and ICIs (anti-PD-1 anti-body w/wo anti-CTLA-4 antibody) increased the infiltration of CD8+ T cells and CD107a+ CD8+T cells, which are considered activated CD8+ T cells, into the tumor tissues (Figs. 2b, 4b).