The low therapeutic efficacy and potential long-term toxicity of antitumor treatments seriously limit the clinical application of phototherapies. Herein, we develop a degradable phototheranostic nanoplatform for NIR-II fluorescence bioimaging-guided synergistic photothermal (PTT) and photodynamic therapies (PDT) and immune activation to inhibit tumor growth. The phototheranostic nanoplatform (CX@PSS) consists of multidisulfide-containing polyurethane loaded with a photosensitizer CX, which can be specifically degraded in the GSH overexpressed tumor microenvironment (TME) and exhibits good NIR-II fluorescence, photodynamic, and photothermal properties. Under 808 nm light irradiation, CX@PSS exhibits efficient photothermal conversion and ROS generation, which further induces immunogenic cell death (ICD), releasing tumor-associated antigens and activating the immune response. In vitro and in vivo studies confirm the potential of CX@PSS in NIR II FL imaging-guided tumor treatments by synergistic PTT, PDT, and immune activation. This work is expected to provide a new pathway for clinical applications of imaging-guided tumor diagnosis and treatments.

中文翻译：

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TME 触发的可降解光疗纳米平台，用于 NIR-II 荧光生物成像引导光疗和免疫激活


抗肿瘤治疗的低疗效和潜在的长期毒性严重限制了光疗的临床应用。在此，我们开发了一种可降解的光治疗纳米平台，用于 NIR-II 荧光生物成像引导的协同光热（PTT）和光动力疗法（PDT）以及免疫激活以抑制肿瘤生长。光治疗纳米平台（CX@PSS）由负载有光敏剂CX的含多二硫化物的聚氨酯组成，可以在GSH过表达的肿瘤微环境（TME）中特异性降解，并表现出良好的NIR-II荧光、光动力和光热性能。在808 nm光照射下，CX@PSS表现出高效的光热转换和ROS生成，进一步诱导免疫原性细胞死亡（ICD），释放肿瘤相关抗原并激活免疫反应。体外和体内研究证实了 CX@PSS 通过协同 PTT、PDT 和免疫激活在 NIR II FL 成像引导肿瘤治疗中的潜力。该工作有望为影像引导肿瘤诊断和治疗的临床应用提供新途径。