7.3　Challenges and Perspectives

Biomedical polymers can protect the loaded drugs，melanoma antigens and immune stimulators from the surrounding biological environment（e.g.，being reduced by various enzyme degradation），while extending their biological half-life and reducing the systemic toxicity.The polymer nano-drug carriers can also deliver the loaded melanoma antigens to the specialized APCs to improve the delivery efficiency of the antigens，thereby improving the activation efficiency of the melanoma antigen specific T cells.Otherwise，the polymer carriers can achieve the co-delivery of melanoma antigens and immunoadjuvants，further improve the immune effect of the antigen specific T cells and have synergistic effect with other immune therapies.Therefore，carriers based on biomedical polymers have a great application prospect in the immune treatment of melanoma.Although biomedical polymers have made some progress in the field of immunotherapy of melanoma，there are still some basic scientific problems（e.g.，the biodistribution in various organs and their metabolic pathways；the acute toxicity，subchronic toxicity，chronic toxicity，genotoxicity，and reproductive toxicity）need to be solved before clinical application.With the further understanding of the properties of various polymer materials，the design of various nanomaterials，micromaterials or macroscale polymer materials based on different clinical needs will further improve the efficacy of melanoma immunotherapy.(https://www.daowen.com)