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Cancer immunotherapy effect can be greatly enhanced by other methods to induce immunogenic cell death (ICD), which has profoundly affected immunotherapy as a highly efficient paradigm. However, these treatments have significant limitations, either by causing damage of the immune system or limited to superficial tumors. Sonodynamic therapy (SDT) can induce ICD to promote immunotherapy without affecting the immune system because of its excellent spatiotemporal selectivity and low side effects. Nevertheless, SDT is still limited by low reactive oxygen species yield and the complex tumor microenvironment. Recently, some emerging SDT‐based nanomedicines have made numerous attractive and encouraging achievements in the field of cancer immunotherapy due to high immunotherapeutic efficiency. However, this cross‐cutting field of research is still far from being widely explored due to huge professional barriers. Herein, the characteristics of the tumor immune microenvironment and the mechanisms of ICD are firstly systematically summarized. Subsequently, the therapeutic mechanism of SDT is fully summarized, and the advantages and limitations of SDT are discussed. The representative advances of SDT‐based nanomedicines for cancer immunotherapy are further highlighted. Finally, the application prospects and challenges of SDT‐based immunotherapy in future clinical translation are discussed.

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Oral antioxidant nanozymes bring great promise for inflammatory bowel disease (IBD) treatment. To efficiently eliminate reactive oxygen species (ROS), various metal‐based nanozymes have been developed for the treatment of IBD but their practical applications are seriously impaired by unstable ROS‐eliminating properties and potential metal ion leakage in the digestive tract. Here, the authors for the first time propose metal‐free melanin nanozymes (MeNPs) with excellent gastrointestinal stability and biocompatibility as a favorable therapy strategy for IBD. Moreover, MeNPs have extremely excellent natural and long‐lasting characteristics of targeting IBD lesions. In view of the dominant role of ROS in IBD, the authors further reveal that oral administration of MeNPs can greatly alleviate the six major pathological features of IBD: oxidative stress, endoplasmic reticulum stress, apoptosis, inflammation, gut barrier disruption, and gut dysbiosis. Overall, this strategy highlights the great clinical application prospects of metal‐free MeNPs via harnessing ROS scavenging at IBD lesions, offering a paradigm for antioxidant nanozyme in IBD or other inflammatory diseases.

Non‐invasive localization of lesions and specific targeted therapy are still the main challenges for inflammatory bowel disease (IBD). Ta, as a medical metal element, has been widely used in the treatment of different diseases because of its excellent physicochemical properties but is still far from being explored in IBD. Here, Ta2C modified with chondroitin sulfate (CS) (TACS) is evaluated as a highly targeted therapy nanomedicine for IBD. Specifically, TACS is modified with dual targeting CS functions due to IBD lesion‐specific positive charges and high expression of CD44 receptors. Thanks to the acid stability, sensitive CT imaging function, and strong reactive oxygen species (ROS) elimination ability, oral TACS can accurately locate and delineate IBD lesions through non‐invasive CT imaging, and specifically targeted treat IBD effectively because high levels of ROS are a central factor in the progression of IBD. As expected, TACS has much better imaging and therapeutic effects than clinical CT contrast agent and first‐line drug 5‐aminosalicylic acid, respectively. The mechanism of TACS treatment mainly involves protection of mitochondria, elimination of oxidative stress, inhibiting macrophage M1 polarization, protection of intestinal barrier, and restoration of intestinal flora balance. Collectively, this work provides unprecedented opportunities for oral nanomedicines to targeted therapy of IBD.