After excluding CD3+/CD19+/CD11b+/NK1.1+/dead cells and positive gating for CD45+ cells (Fig. S2), we observed an increase of c-kit/FcεRIα double-positive cells in colon of DSS-induced colitis mice with respect to control mice; moreover, we found a more pronounced accumulation in the tumor masses of AOM/DSS mice compared to inflamed colon and tumor-free surrounding tissue (Fig. 1B, C). Here, FCER1A is linked to colitis.