Synergistic nanoplatform of M1 macrophage-derived extracellular vesicles and MoS for tumor-targeted photoimmunotherapy in bladder cancer.

Bladder cancer is among the most challenging malignancies, necessitating innovative therapeutic strategies to address tumor recurrence and progression. This study investigates the therapeutic potential of M1 macrophage-derived extracellular vesicles (M1 EVs) engineered with molybdenum disulfide (MoS), forming a hybrid system (M1 EVs@MoS) for combined photothermal and immunotherapy. MoS nanoparticles provide excellent photothermal conversion and photocatalytic efficiency under near-infrared (NIR) irradiation, enabling precise tumor ablation and enhanced reactive oxygen species (ROS) generation. Concurrently, M1 EVs modulate the tumor microenvironment by promoting M1 macrophage polarization and enhancing antitumor immunity. Our findings demonstrate that M1 EVs@MoS significantly suppresses bladder tumor growth through synergistic mechanisms: modulation of immune cytokines, robust photothermal effects, and oxidative stress induction. Immunofluorescence analysis revealed increased CD8 T-cell infiltration, dendritic cell activation, and reduced PD-L1 expression, indicating immune reprogramming within the tumor microenvironment. Furthermore, the biomimetic properties of M1 EVs facilitated tumor-specific delivery, minimizing off-target effects. This multifunctional platform offers a promising approach to integrate photothermal therapy with immune modulation, addressing the limitations of conventional therapies and paving the way for advanced precision oncology. Future studies will focus on optimizing formulation parameters, evaluating efficacy, and exploring combinatory treatments with immune checkpoint inhibitors.