IL4R and neoplasm: To investigate whether the observed inhibition of tumor growth was due to direct targeting of IL‐4R+ tumor cells, to depletion of IL‐4R+ MDSCs and TAMs, or to a combination of the two, we orthotopically implanted IL‐4R+ 4T1 cells in an IL‐4R KO mouse strain (IL‐4Rα−/−) and administered either PBS or DABIL‐4 thrice weekly starting on day 7.