CCL2 is required for DE-DLBCL to promote tumor progression and an immunosuppressive TME. (A) MYC- and/or BCL2-stable expressing A20 cells and their phosphorylated p65 and CCL2 expression. (B) Experimental scheme. (C) BALB/c mice were subcutaneously implanted with MYC/BCL2-overexpressing A20 cells or control (con) A20 cells and then IP injected with clodronate or con liposomes as described above. Tumor growth was measured every 2 or 3 days. Tumors were resected 22 days postinjection (d.p.i.). (D) BALB/c mice were subcutaneously implanted with MYC/BCL2-overexpressing A20 cells or control A20 cells and then IP injected with anti-CCL2 nAbs, as described above. At 40 d.p.i, the mice were euthanized, and the tumor weight was measured. Tumor-infiltrating immune cells were analyzed using flow cytometry. The total number of macrophages and their macrophage differentiation markers expression (E), T-cell subsets (F), and IFN-γ or granzyme B producing T cells (G) are shown. Representative images of CD8, granzyme B, and CD206 immunohistochemical staining of tumor tissues (H). The data in the histograms are presented as mean ± SEM of 5 independent experiments. ∗P < .05; ∗∗P < .01; ∗∗∗P < .001. Scale bar, 200 μm. IFN-γ, interferon gamma; iso, isotype control; MFI, mean fluorescence intensity.