CD4 and neoplasm: While presentation of tumor Ags is generally thought to occur within primary tumor sites or their draining lymph nodes, a recent report demonstrated that intravascular MHCII+ monocytes are able to present Ag to CD4+ T cells within inflamed glomeruli vasculature.84 Whether similar interactions between T cells and monocytes can occur within tumor vasculature or following engulfment of tumor‐derived material in circulation remains an interesting direction for further exploration.