CD80 and neoplasm: The Fe3O4-SWCNT@M1 can maintain the M1 subtypes (with the high expression of CD80) even in the M2 medium, as shown in Fig. 3A–C; in addition, the Fe3O4-SWCNT@M1 can specifically cleave 4T1 tumor cells by lactate dehydrogenase (LDH) method, as shown in Fig. 3D. After intravenous injection of Fe3O4-SWCNT@M1 (5 mg/kg with 3 × 106 cells/mouse), the tumor progression was inhibited with activated tumor immune response.