Research Progress of Anti-tumor Drug Delivery Systems Based on CD47-SIRPα Axis

Macrophages are an important part of tumor microenvironment, and tumor cells avoid phagocytosis by expressing CD47 to interact with SIRPα on the surface of macrophages. At present, the researches on restoring the phagocytic function of macrophages by blocking the interaction of CD47-SIRPα axis have received widespread attention, and a variety of drugs including anti-CD47 antibodies have been put to clinical trials. However, common hematological toxicity has limited the clinical application of these drugs. In addition to screening out drugs that specifically act on tumor cells, encapsulating CD47 inhibitors through drug delivery systems is an effective strategy for tumor treatment. Based on the structure and signaling pathway of CD47-SIRPα axis, this review summarizes the delivery systems targeting CD47-SIRPα axis, including gel matrix, antibody-drug conjugates and nano-delivery systems constructed by different carrier materials, in order to provide reference for clinical development of drugs.