IL13RA1 and intestinal neoplasm: Flow cytometry analysis showed that M-MDSCs from intestinal tumors upregulated the IL-4Rα and IL-13Rα1 receptor subunits as compared to the few M-MDSCs in the normal gut (Fig. 4, A and B), while G-MDSCs expressed IL-4Rα but not IL-13Rα1 (fig.