IGHE and cancer: The Ab deposition in the tumor may contribute to effector cell-mediated tumor killing, and IgE has been reported to promote the macrophage polarization into M1 phenotype [33] and modulate macrophages against cancer [34, 35], while we noted increased intratumoral M1 macrophages in Prdm1fl/flFoxp3YFP-Cre mice (Fig. 2g).