AURKA is required for hematopoiesis. (A) Western blot of Aurka in bone marrow lysates prepared from Aurka^fl/fl (WT), Aurka^fl/+/Mx1-Cre (Aurka^+/−), and Aurka^fl/f/Mx1-Cre (Aurka^−/−) mice 14 days after 3 doses of pI-pC treatment. Heat shock protein 70 (Hsc70) is included as a loading control. (B) Survival curve for WT, Aurka^+/−, and Aurka^−/− mice after pI-pC treatment. Day 1 refers to the day of the first pI-pC injection. The significance of the difference in survival curves was calculated by log-rank test. P = .0002. n = 4 to 5 mice per group, respectively. (C-E) Analysis of the peripheral blood white blood cell count, hemoglobin, and platelet counts from mice 14 days after the first pI-pC injection. Data are shown as the means ± standard deviation (SD). (F) H&E-stained sections of bone marrow, spleen, and liver from control and homozygous-deleted mice 14 days after the first pI-pC injection. Peripheral blood smears from control and homozygous-deleted mice were stained with May-Grünwald Giemsa. Slides were viewed with a Leica DM4000B microscope fitted with a 10× Leica HCX PL Fluorotar objective. Images were acquired with Leica DFC320 camera and Leica LAS v4.4 software at room temperature. (G) Bone marrow cellularity 14 days after pI-pC treatment of control, heterozygous, and homozygous-deleted mice. Data are shown as the means ± SD. n = 6. (H) Loss of Aurka in vivo results in increased apoptosis as measured by annexin V staining 14 days after pI-pC treatment. (Left) Representative flow cytometry plot. (Right) Bar graph with mean ± SD. n = 3. *P < .05; **P < .01; ***P < .001.