CD274 and liver cancer: In addition, studies have shown that CD19+ macrophage subpopulation exists in liver cancer, which enhances mitochondrial metabolism by upregulating the expression of transcription factor PAX5 [62], thereby inhibiting lysosome function, increasing the expression of immunosuppressive proteins CD73 and PD-L1 on cell surface, inducing the formation of immunosuppressive microenvironment and promoting the progression of liver cancer, confirming that cell therapy targeting CD19+ macrophages can significantly improve the immunotherapy effect of liver cancer.