TNFRSF4 and neoplasm: While MDSCs were not examined in this manuscript, we suggest that future studies evaluate whether systemic, or tumor associated, MDSC frequencies are higher in model conditions that are less responsive to the CpG + OX40 in-situ vaccine, and whether IT injections of CpG + OX40 may act to decrease the suppressive potential of MDSCs allowing a measurable anti-tumor immune response under some model conditions.