Impact of dematin deficiency on primitive and definitive erythropoiesis. (A) Primitive erythrocytes (Cytospin) from peripheral blood of embryos at E13.5. Wright-Giemsa stain. Shown at ×60 original magnification. (B) Morphology of intact embryos at E14.5 endowed with definitive erythropoiesis. (C) Quantification of mouse fetal erythroblast enucleation in vivo by flow cytometry. The percentage of enucleated cells is indicated in the lower right quadrant. (D) Statistical analysis of erythroblast enucleation in vivo (E14.5). Unpaired t test, mean ± SD, ***P < .001. WT, n = 5; HET, n = 5; FLKO, n = 3. (E) Analysis of mouse fetal liver erythroblast enucleation in vitro. TER119 negative erythroid progenitor cells of E14.5 fetal liver cells from WT and DAKO were isolated and quantified after 24 and 48 hours in culture by flow cytometry using Hoechst 33342 and PE-TER119. Circled R4 region represents the enucleated fraction (Hoechst^lowTER119^high). (F) Percentage of enucleated cells is indicated. Unpaired t test, **P < .01. Mean ± SD; WT, n = 3; DAKO, n = 3.