Restricted expression of Gfi-1B in hematopoietic cells detected by RT-PCR.

(A) Expression of human Gfi-1B. Cells analyzed are bone marrow CD34⁺CD38⁻ stem cells, CD34⁺ progenitor cells, glycophorin A (GPA)⁺erythroblasts, CD41⁺ megakaryocytes, CD13⁺myeloid progenitors, CD14⁺ macrophage, CD15⁺granulocytes, CD56⁺ NK cells, and peripheral blood CD3 T⁺ cells, CD19⁺ B cells, CD4⁺ T cells, and CD8⁺ T cells. (B) Expression of murineGfi-1B. Cells analyzed are bone marrow CD34⁻c-Kit⁺Sca-1⁺ lineage marker⁻ stem cells (34^–KSL), KSL progenitors, lineage marker⁻ cells (Lin⁻), Mac-1⁺ myeloid cells, TER119⁺ erythroblasts, B220⁺ B cells, spleen Thy-1⁺ T cells, NK1.1⁺ natural killer (NK) cells, B220⁺ B cells, and thymic CD4⁻CD8⁻ T cells (DN), CD4⁺CD8⁺ T cells (DP), CD4⁺CD8⁻ T cells (CD4SP), and CD4⁻CD8⁺ (CD8SP). (C) Expression of human Gfi-1B during erythroid differentiation. Human peripheral blood CD34⁺ cells mobilized by G-CSF were collected and cultured under conditions that preferentially drive erythroid differentiation (details in “Materials and methods”). After incubation for the number of indicated days, cells were collected and subjected to RT-PCR analysis. The percentages of GPA⁺cells, BFU-Es, and CFU-Es in cells on the indicated days are as follows: day 3 (18.1%, 17.2%, 10.8%), day 5 (51.4%, 5.5%, 37.6%), day 7 (80.4%, 0%, 24.8%), and day 10 (91.6%, 0%, 2.1%). “Water” represents the negative control without template. RT-PCR was performed on normalized cDNA templates. PCR products were electrophoresed on agarose gels and visualized by ethidium bromide staining.