The hybrid nano-platform based on ZIF-8 realises the synergistic therapy of tumour chemo-immunotherapy

Immunotherapy has attracted widespread attention as a new tumour treatment method. Because of the low response rate, immunotherapy is only effective for some patients. With the continuous exploration of tumour immunity, the concept of immunogenic cell death (ICD) has brought new vitality to many cancer treatment methods, including chemotherapy. However, the immune effect of ICD induced by chemotherapy is often influenced by immune cell types, the tumour microenvironment, and other factors. Based on this, we constructed a hybrid nano-platform based on ZIF-8 to realise chemo-immunotherapy for tumour treatment by loading the chemotherapy drug doxorubicin (DOX), the indoleamine 2,3-dioxygenase (IDO) inhibitor 1-methyltryptophan (1MT), and the immune adjuvant CpG. In order to ensure the smooth arrival of the nanoparticles at the tumour site, carboxymethyl chitosan (CMCS) was introduced for surface modification to enhance the stability of the nanoparticles in vivo. The hybrid nano-platform not only successfully induced ICD in tumour cells but also achieved an 85.6% inhibition rate in the 4T1 tumour model, proving its excellent tumour-killing ability. In conclusion, the successful construction of the hybrid nano-platform provides a new idea and method for multi-modal combined therapy of tumours.