The results showed that CD19‐81‐293‐EXO treatment recruited similar levels of CD45+ leukocytes (Figure 7b); CD68+ macrophages and monocytes (Figure 7c); CD11c+ dendritic cells (Figure 7d); and CD3+, CD4+, and CD8+ T cells (Figure 7e) into the tumor compared to the control group. Here, CD19 is linked to neoplasm.