Abstract In the tumor microenvironment (TME), one of the major functions of tumor-recruited CD11b+ cells are the suppression of the T-cell-mediated anti-tumor immune response. β-glucan could convert the phenotype of tumor-recruited CD11b+ cells from the suppressive to the promotive, and enhanced their anti-tumor effects. However, β-glucan could enhance the PD-1/PD-L1 expression on