Autologous tumor antigens and boron nanosheet-based nanovaccines for enhanced photo-immunotherapy against immune desert tumors

Personalized therapeutic vaccines against immune desert tumors are an increasingly important field in current cancer immunotherapy. However, limitations in neoantigen recognition, impotent immune cells, and a lack of intratumoral infiltrated lymphocytes pose challenges for the cancer vaccines. Resected tumors contain various of patient-specific tumor autoantigens (TA), and its derived photonanovaccines have unique competency to overcome abovementioned barriers. We constructed a novel personalized photonanovaccine (B@TA-R848) with surgically sourced TA modified on two-dimensional boron nanosheets (BNSs) via polydopamine coating and loaded with immune adjuvant R848. B@TA-R848 has good properties of drug delivery and release, photoacoustic imaging, photothermal effect, and biocompatibility. In a mouse triple-negative breast cancer model, B@TA-R848-based photonanovaccine induced effective systemic antitumor immune responses, altered the local tumor microenvironment, and increased the intratumoral infiltration of immune cells. The combined photo immunotherapy could significantly inhibit tumor growth, recurrence, and metastasis. This work develops a novel photonanovaccine for low immunogenicity and high metastatic potential tumors, which is of great significance for exploring the clinical development of personalized tumor vaccines against immune desert tumors.