A. Spleen morphology of three month-old WT and IRF8 TKO mice. B. Percentages of CD11b+Gr1+ MDSCs in thymus (Thy), spleen (SP), lymph node (LN), bone marrow (BM) and blood of WT and IRF8 TKO mice. Shown are representative results from one mouse of three mice. C. Quantitation of CD11b+Gr1+ MDSCs in the indicated tissues of WT (n=3) and IRF8 TKO (n=3) mice. Column: mean, bar: SD. ** p<0.01. D. Subsets of Gr1+ (Ly6C+ and Ly6G+) myeloid cells in SP and BM. Shown are representative results from one mouse of three mice. E. Quantification of subsets of Gr1+ myeloid cells in SP and BM of WT (n=3) and IRF8 TKO (n=3) mice as shown in D. Column: mean, bar: SD. **p<0.01.