CD4 and neoplasm: Apart from that, an increased population of CD3+CD8+T and CD3+CD4+T cells of tumor and spleen tissues were detected, especially in mice treated with ICG@Hydrogel+L+αPD‐L1 among all the groups, indicating that ICG‐locking gel implantation combined with PD‐L1 triggers T cell significantly mediated adaptive antitumor immune response (Figure 9c,d, Figure S12).