T cells | PD-1+CD8+ T cell | Tumor cells | Induce T cell exhaustion | Liver, pancreatic, HNC, NSCLC, early breast cancer | 9–12 |
| PD-L1+ T cell | Neighboring effector T cells, macrophages | Promote STAT6-dependent M2-like macrophage differentiation and suppress neighboring effector T cells | Pancreatic ductal adenocarcinoma | 32 |
B cells | PD-1hiCD5hiCD24-/+CD27hi/+CD38dim B cell | T cells | T-cell dysfunction and foster disease progression | Hepatoma | 14 |
| PD-1+ B cell | CD4+ and CD8+ T cells | Inhibit CD4+ and CD8+ T cell proliferation | Thyroid tumors | 33 |
| PD-L1hi B cell, PD-1-PD-L1+CD19+, PD-L1+CD24+CD38+CD19+ B cell | T cells | Inhibit T cell proliferation and promote the formation of Tregs | Breast cancer | 34–37 |
| PD-L1+CD155+IL-10+TGF-β+ B cell | CD8+ T cells | Inhibit CD8+ T cell proliferation, IFN-γ production, and expression of the granzyme B | GBM | 38 |
| PD-L1+IgA+IL-10-producing Plasmocyte | CD8+ T cells, CTLs | Induce CD8+ T cell depletion and inhibit the immune response of CTLs | Prostate tumors | 39 |
| PD-L1+IgA+IL-10+ Plasma cell | CD8+ T cells | Inhibit activation of CTLs | Hepatocellular carcinoma | 33 |
| PD-L1+IgA+CD19+ B cell | CD8+ T cells | Inhibit the proliferation and activation of CD8+ T cells | Colorectal cancer | 40 |
NK cells | PD-1+NKG2A-KIR+CD57+ NK cell | Tumor cells | Low proliferative response of NK cells and impaire antitumor activity | Ovarian cancer, colorectal cancer, gastric cancer, ESCC, HCC, biliary cancer, melanoma | 17,44–46 |
DCs | PD-1+CD11c+ DC | CD8+ T cells | Inhibit the secretion of perforin and granzyme B by CD8+ T cells | HCC | 48 |
| PD-1+PD-L1+CD11c+CD8α-Gr-1 lo / int DC | T cells, DC cells | Inhibit T cell proliferation, regulate cytokine production by DCs and maintain their immature phenotype | Ovarian cancer | 19 |
| PD-L1+ DC | CIK cells | Reduce the ability of DC-CIK-mediated melanoma cell killing assays | Melanoma | 51 |
| PD-L1+ DC | T cells | Induce the apoptosis of T cells and increase the percentage of Tregs | HCC | 62 |
Mononuclear macrophages | PD-1+CD11c+MHC-II+ CD4+CD68+ TAM | Tumor cells | Decreased phagocytosis | Colorectal cancer | 20 |
| PD-1+ Macrophage | Tumor cells | Weaken the cytotoxic effect on mesothelioma cells | Malignant pleural mesothelioma | 52 |
| PD-L1+HLA-DRhighCD68+ Macrophage | T cells | Induce T cell anergy and reduce IFN-γ production by T cells | HCC | 21 |
| PD-L1+ CD68+ Macrophage | T cells | Decrease the proportion of CD8+ T cells and promote T cell apoptosis | HCC | 53 |
| PD-L1+F4/80+ Macrophage | CD8+ T cells | Reduce the number of activated T lymphocytes | Bladder cancer | 54 |
| PD-L1+CD11b+F4/80+ Macrophage | CD4+ and CD8+ T cells | Inhibit CD4+ and CD8+ T cell proliferation | Melanoma | 55 |
| PD-L1+CD45+CD11b+ Macrophage | T cells | Induce T cell apoptosis | Glioma | 63 |
| PD-L1+CD11b+F4/80+ TAM CD169+ Macrophage | T cell | Inhibit T cell-mediated antitumor response | TNBC | 64,65 |
| PD-L1+CXCL8+CD68+CD45+ Macrophage | CD8+ T cells | Inhibit CD8+ T cells function | Gastric cancer | 56 |
| PD-L1+HLA-DrhiCD14+ TAM | T cells | Protect TAMs from being killed by cognate effector T cells | Early-stage lung tumor | 57 |
Granulocytes | PD-L1+CD45+CD117+Fc?RI+ Mast cell | T cells | Inhibit normal T cell immunity | Gastric cancer | 25 |
| PD-L1+CXCL5+CXCR4+ CCR5+Adam1+Nos2+Neutrophil | T cells | Immunosuppressive effects in T cell proliferation | Cutaneous melanoma | 59 |
| PD-L1+ CD54+ Neutrophil | T cells | Suppresse normal T-cell immunity | Gastric cancer | 24 |
| PD-L1+Tollip+ Neutrophil | T cells | Reduce T cell activation, suppress tumor immune surveillance and increase the tumor burden | Colorectal cancer | 66 |
| PD-L1hiCD11bhiCD80lowIRAK-M+ Neutrophil | T cells | Inhibit T cell activation | Colitis-associated tumor | 67 |
MDSCs | PD-L1+Gr-1+CD11b+ MDSC | MDSCs, T cells | Increase MDSC-mediated T cell suppression, increased IL-10 and IL-6 secretion of MDSC and inhibited IFN-γ production of T cells | Mammary carcinoma, LLC, melanoma, colon carcinoma | 27 |
| PD-L1+Gr-1+CD11b+ MDSC | T cells | Inhibit T cell activation | Melanoma | 61 |