IHC of CD8+ in animal transplanted tumor specimens indicated that, compared with mice injected with M2‐Exos or M2/sh‐NC‐Exos alone, the M2‐Exos+Annexin V, or M2/sh‐1232#1‐Exos group had significantly increased expression of CD8+ (Figure 3f,g; Figure S3d, Supporting Information). Here, CD8A is linked to neoplasm.