Figure 1. Characteristics of erythroid cell lines derived from mouse ES cells, MEDEP.
(A) Morphology of two erythroid cell lines, MEDEP-E14 and MEDEP-BRC5. Wright-Giemsa staining. (B) Cytokine dependent proliferation. Cells (1×105 cells/ml) were cultured in various conditions for three days. The added factor(s) is shown at the bottom. None, no specific factor. SCF, stem cell factor. EPO, erythropoietin. Broken line, the number of cells at the start of culture. Values are mean±S.D. Results shown are representative of several independent experiments performed at different time points after establishment of the cell lines. (C) RT-PCR analyses. Oct-3/4 and Nanog, transcription factors specific for ES cells. GATA-1 and EKLF (Erythroid Krüppel-like factor), transcription factors specific for erythroid cells. EPOR, erythropoietin receptor. GAPDH, glyceraldehyde-3-phosphate dehydrogenase. NC, negative control without cDNA. Day 0, E14TG2a cells before differentiation. Day 4, 7, 10, 14 and 21, the cells following induction of differentiation into hematopoietic cells from E14TG2a by the method described in Table 1 (Method A). The cycle numbers performed in each PCR are shown at the right. Results shown are representative of two independent experiments.