TNF and neoplasm: In our model, both MHCII+ and MHCII− Ly6ChiCCR2+ cells are present approximately at the same number but the amount of these monocyte-derived cells producing TNF increases after the administration of poly A:U, in accordance with previous in vitro reports, that show that tumor-supporting myeloid cells can be converted to tumoricidal effectors by activating TLR3 (37).