IL-1RAP is a transmembrane protein that potentiates multiple inflammatory signaling pathways, including IL-1, IL-33, IL-36G, and stem cell factor (27, 28), and it has the unique feature of being expressed at higher levels in stem and progenitor cells from myeloid leukemia patients compared to normal HSPCs (49–52). Here, KITLG is linked to myeloid leukemia.