Lamin B but not Lamin A/C is expressed in mouse FL erythroblasts, whereas human bone marrow erythroblasts have variable expression of Lamin A/C but no Lamin B. (A) Confocal single optical sections showing mouse FL erythroblasts immunostained for (a) Lamin A/C, or (a′) Lamin B along with Ter119 and Hoechst. (B) Confocal single optical sections of human bone marrow cells immunostained for (b) Lamin A/C or (b′) Lamin B along with GPA and Hoechst. Bars, 4 µm.