Platelets camouflaged nanovehicle improved bladder cancer immunotherapy by triggering pyroptosis

The regulation of immunosuppressive microenvironments in tumors through targeted drug delivery shows promise for immunochemotherapy in bladder cancer. Drawing inspiration from stealth tactics, a nano-vehicle camouflaged with platelets (PLTs) was developed to enable precise delivery and trigger pyroptosis for tumor immunotherapy. Methods: Erdafitinib (Erda) was nano-sized and encapsulated in PLTs to construct nano-Erda@PLT. Characterization of the PLTs camouflaged nano-vehicle was conducted using Zetasizer, SEM, and confocal laser scanning microscopy. The excellent targeted delivery property of the PLTs nano-vehicle was investigated through intravital imaging, three-dimensional microspheres, and SEM. Validation of pyroptosis in bladder cancer cells via the caspase-3/GSDME pathway was performed using western blot, immunofluorescence, and ELISA tests. Immunotherapy by nano-Erda@PLT treatment in vivo was confirmed using H&E, immunohistochemical, and flow cytometry. Lastly, the side effects of nano-Erda@PLT were assessed. Results: Proteomic analysis revealed that the activation of p-selectin on platelets facilitated the identification of nano-Erda@PLT targeted therapies. Nanoscale of Erda released in response to adenosine diphosphate, facilitated intratumoral permeation. This could contribute to an upregulation of the key proteins of pyroptosis, caspase-3 and GSDME, in bladder cancer cells due to nano-Erda@PLT accumulation. Additionally, the burst release of numerous inflammatory factors may enhance the system's adaptive immune response. In a bladder cancer animal model, this treatment was found to regulate the immunosuppressive microenvironment, resulting in effective tumor immunotherapy and the induction of a long-lasting, robust immune memory. Conclusion: PLTs-camouflaged nano-vehicles enable nano-Erda-mediated tumor immunotherapy through the induction of pyroptosis. These findings introduce a novel approach in exploring nanomaterial-mediated pyroptosis for cancer immunotherapy.