A multi-functional drug delivery nanosystem release of TLR-7 immunostimulant and OKT3 induced efficient cancer immunotherapy.

Immunotherapy has some shortcomings such as off-target toxicity, treatment time and poor immunogenicity, which limit its therapeutic effect. Nanomaterials are particularly attractive in immunotherapy due to their drug delivery capabilities. Nano drug delivery system loaded with Toll-like receptor (TLR) agonist imiquimod (IMQ) and CD3 immune antibody OKT3 is constructed by using polydopamine (PDA) and CaCO. While PDA-IMQ@CaCO-OKT3 (PICO NPs) drug delivery system has the advantages of high biocompatibility, low toxicity, degradability. Antitumor studies in vitro and in vivo have shown that the system can effectively inhibit the proliferation of mouse breast cancer cells and the activity of Regulatory T Cells (Tregs), activate immunogenic cell death (ICD), and enhance the activity of antigen-presenting cells (APCs). Effectively eliminate tumor immunosuppression and fully activate immune function.