Icmt deficiency reduces the accumulation of immature myeloid cells and tissue infiltration in mice with K-RAS–induced MPD. (A) White blood cell counts of Icmt^fl/+K^LSLM and Icmt^fl/flK^LSLM mice. Blood was analyzed before and weekly after pI-pC injections. (Icmt^fl/+K^LSLM: week 0-8, n = 11-19; week 9-14, n = 4-6; Icmt^fl/flK^LSLM: week 0-7, n = 7-20; week 8-14, n = 1-5). (B) White blood cells were evaluated in blood smears from Icmt^fl/+K^LSLM (▭) and Icmt^fl/flK^LSLM mice (▬) before pI-pC injections (n = 6-7), at 5 to 7 weeks (n = 5), and at 13 to 14 weeks after pI-pC injections (n = 2-3). Shown is the percentage of immature cells (ie, myeloblasts, myelocytes, metamyelocytes, band cells, and pelgeroid cells). (C) Photographs of typical blood smears from panel B (original magnification ×100; 1.30 NA oil objective). (Top right panel) → represents band cell; ⇉, pelgeroid cell; ▲, erythroblast. The large cell to the right of the erythroblast is a myeloblast. (D) Hemoglobin concentrations measured in the blood samples shown in panel A. (E) Hematoxylin and eosin–stained sections of liver and spleen of mice killed 13 weeks after pI-pC injections (original magnification ×20; 0.50 NA objective). (F) Kaplan-Meier curve showing survival of Icmt^fl/+K^LSLM (n = 21) and Icmt^fl/flK^LSLM (n = 22) mice.