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

This is the authors' abstract. We don't add key points for this paper.

Cancer immunotherapy has shown tremendous promise in various cancers. 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. This controlled re-exposure allows the accumulated T cells to attack the tumor cells in a more activated and anti-exhaustion state, maximizing their tumor-killing potential. Moreover, BPB not only enhances immediate tumor regression but also triggers systemic immune activation and durable memory responses, enabling long-term protection against tumor rechallenge and effective control of multifocal tumors. Collectively, our BPB for modulating the T cell-tumor cell interaction has great prospects for advancing cancer immunotherapy.