Laser-Activatable in Situ Vaccine Enhances Cancer-Immunity Cycle

The immune response in cancer reflects a series of carefully regulated events; however, current tumor immunotherapies typically address a single key aspect to enhance anti-tumor immunity. In the present study, we developed a nanoplatform (Fe 3 O 4 @IR820@CpG)-based immunotherapy strategy that targets the multiple key steps in cancer-immunity cycle: 1) promotes the release of tumor-derived proteins (TDPs), including tumor-associated antigens and pro-immunostimulatory factors), in addition to the direct killing effect, by photothermal (PTT) and photodynamic therapy (PDT); 2) captures the released TDPs and delivers them, together with CpG (a Toll-like receptor 9 [TLR-9] agonist) to antigen presenting cells (APCs) to promote antigen presentation and T cell activation; 3) enhances the tumor-killing ability of T cells by combining with anti-programmed death ligand 1 antibody (α-PD-L1), which collectively advances our outstanding of the anti-tumor effects on colorectal, liver and breast cancers. The broad-spectrum anti-tumor activity of Fe 3 O 4 @IR820@CpG with α-PD-L1 demonstrated that optimally manipulating anti-cancer immunity not singly but as a group provides promising clinical strategies. This article is protected by copyright. All rights reserved