FIP200 deletion led to increased HSC cell cycling and myeloid differentiation. (A-B) The percentage of BrdU positive fetal liver cells (A) and fetal HSCs (B) in E14.5 control and CKO mice after 2 hours BrdU pulse. Representative FACS profile of fetal HSCs is shown on the right in panel B. P4 represents the BrdU⁺ population. (C-D) Frequency (C) and number (D) of different lineage fetal liver cells of E14.5 control and CKO mice. Representative FACS profile of Mac1⁺Gr1⁺ population is shown on the right in panel C. n = 6-13, *P < .05. Data are mean ± SE. (E) Wright-Giemsa staining of the blood smears from E18.5 control and CKO embryos. The arrows indicate neutrophils. (F) Number of Mac1⁺Gr1⁺ cells/μL peripheral blood of E18.5 control and CKO embryos. Representative FACS profile is shown on the right. n = 3-15, *P < .05. Data are mean ± SE.