Controlling T cell–tumor cell interaction with a biomimetic physical barrier for cancer immunotherapy

However, current strategies, such as immune checkpoint blockade, primarily restore exhausted T cells but provide only transient efficacy, as the rapid clearance of antibodies. Their limited durability is further hindered by persistent T cell-tumor cell interactions that accelerate T cell exhaustion.

To prevent T cells from sustained exposure to these interactions, we present a hydrogel-based biomimetic physical barrier (BPB) here to create a “protective zone” for T cells. The BPB temporarily blocks T cell-tumor cell interactions and shields T cells from inactivation and exhaustion, allowing them to accumulate and maintain their functional activity in the tumor microenvironment. After sufficient T cell accumulation, the dismantling of BPB triggered by near-infrared light irradiation-induced gel-sol transition will restore the interaction between T cells and tumor cells.