CD8A and neoplasm: Next, we tested the impact of IL-13-ablation on intestinal tumorigenesis in vivo. IL-13-deficiency (Il13tom/tomApc1322T/+) (38) decreased tumor burden (Fig. 4I), and reduced tumor Arg1+ M-MDSCs (Fig. 4J) while increasing IFNγ expression in tumor-infiltrating CD4+ and CD8+ T cells (Fig. 4K and fig.