,Activation of phagocytosis by immune checkpoint blockade

• 作 者: Chia-Wei Li Yun-Ju Lai Jennifer L.Hsu Mien-Chic Hung
• 机 构: Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Ho
• 出 处: 医学前沿
• 发表日期: 2018年4期
• 关键词: CD47 PD-1 PD-L1 immunotherapy TAM phagocytosis macrophage

Inhibition of macrophage-mediated phagocytosis has emerged as an essential mechanism for tumor immune evasion.One mechanism inhibiting the innate response is the presence of the macrophage inhibitory molecule,signal regulatory protein-α (SIRPα),on tumor-associated macrophages (TAMs) and its cognate ligand cluster of differentiation 47 (CD47) on tumor cells in the tumor microenvironment.On the basis of a recently discovered programmed death protein 1 (PD-1) in TAMs,we discuss the potential inhibitory receptors that possess new functions beyond T cell exhaustion in this review.As more and more immune receptors are found to be expressed on TAMs,the corresponding therapies may also stimulate macrophages for phagocytosis and thereby provide extra anti-tumor benefits in cancer therapy.Therefore,identification of biomarkers and combinatorial therapeutic strategies,have the potential to improve the efficacy and safety profiles of current immunotherapies.