**5. Concluding Remarks and Future Perspectives**

From synthetic materials such as functionalized liposomes and micelles inspired by biomembranes to tumor cell-derived membrane vesicle-coated nanoparticles that bind to cell membranes, researchers have pursued suitable carrier materials for tumor immunotherapy. This review focuses on TDMV technology and its application in personalized immunotherapy. Tumor immunotherapy has yielded exciting results in several clinical trials. At the same time, achieving precise targeting and universal efficacy is also a problem for tumor immunotherapies in clinical trials. The choice of any TDMVs can target homologous tumors, overcoming the disadvantages of synthetic particles. TDMVs exploit the biological properties of cells, such as the ability to cross biological barriers, circulate in the body for long periods, interact with other cells and the capability to pass through biological barriers. In particular, the ability to pass through biological barriers and modify tissue toxicity effectively protects the drug from its effects. Unique approaches are utilized by introducing integrated biological components and functions that have synergistic effects and enhance the performance of TDMVs. For example, ligands composed of antibodies, peptides and proteins can be integrated into cell membranes to improve the function of cancer immunotherapy. TDMVs carry tumor cell proteins or genetic material, and their modification enables personalized therapy for all patients, especially for the development of tumor vaccines.

Cancer immunotherapy based on TDMVs technology is an attractive option due to the excellent biocompatibility and versatility, but in practice, there are many challenges to overcome to achieve widespread clinical application. First, the mechanism of action of TDMVs with tumor cells has not yet been fully explained. For example, the biological information carried by TEVs is stochastic in nature, and the mechanism of carrying is still unclear to achieve effective and precise regulation. Its mode of communication with the cell remains unclear. Second, whether the batch reproducibility, homogeneity and storage stability of TDMVs meet the quality manufacturing specification (GMP) standards also limit their further clinical translation. Third, biosafety issues are owing to unknown biological mechanisms. The current system for evaluating biosafety in the clinical setting is not robust, making the safety assessment of TDMVs unconvincing. In addition, personalized immunotherapies based on TDMVs currently have long lead times and high costs, and further exploration of optimization options is needed. However, with greater understanding and creative ideas, the field of TDMV -based nanotechnology can certainly circumvent these issues and drive cell membrane nanotechnology closer to accurate clinical applications.

**Funding:** This research was funded by China Postdoctoral Science Foundation, grant number 2020M683194.

**Data Availability Statement:** Data sharing not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

