Consistently, gene expression and FACS analysis revealed that ME49Δompdc vaccination significantly increased the percentage of CD4+ and CD8+ T cells in tumors and spleens, but not in tumor‐draining lymph nodes (TDLNs), while lowering the expression of PD‐1 in these splenic and intratumoral T cells (Figure S7H–L, Supporting Information). Here, CD4 is linked to neoplasm.