Compared to PLGA/DiR, the average fluorescence intensity of PD‐1‐MM@PLGA/DiR increased by 11.52 times, indicating that PD‐1‐MM@PLGA/RAPA NPs could cross the blood–brain barrier and specifically aggregate at tumor sites with high PD‐L1 expression (Figure 5C). The gene discussed is PDCD1; the disease is neoplasm.