Nano‐optogenetic immunotherapy

Chimeric antigen receptor (CAR) T cell‐based immunotherapy has been increasingly used in the clinic for cancer intervention over the past 5 years. CAR T‐cell therapy takes advantage of genetically‐modified T cells to express synthetic CAR molecules on the cell surface. To date, up to six CAR T cell therapy products have been approved by the Food and Drug Administration for the treatment of leukaemia, lymphoma, and multiple myeloma. In addition, hundreds of CAR‐T products are currently under clinical trials to treat solid tumours. In both the fundamental research and clinical applications, CAR T cell immunotherapy has achieved exciting progress with remarkable remission or suppression of cancers. However, CAR T cell‐based immunotherapy still faces significant safety issues, as exemplified by “on‐target off‐tumour” cytotoxicity due to lack of strict antigen specificity. In addition, uncontrolled massive activation of infused CAR T cells may create severe systemic inflammation with cytokine release syndrome and neurotoxicity. These challenges call for a need to combine nanotechnology and optogenetics with immunoengineering to develop spatiotemporally‐controllable CAR T cells, which enable wireless photo‐tunable activation of therapeutic immune cells to deliver personalised therapy in the tumour microenvironment.