Robust production of HPCs from mouse ESCs by enforced expression of Lhx2. (A) In vitro hematopoietic differentiation of ESCs by OP9 coculture. Undifferentiated ESCs, day 5–, and day 10–induced cels were shown. Original magnification: ×4. (B) Flk1 expression on day 5. (C) The RT-PCR analysis of Lhx2, Gata-1 and Gata-2 expression during ESC differentiation and at hematopoietic sites. YS and AGM indicate yolk sac and aorta/gonad/mesonephros region at E10.5, respectively. (D) Retroviral vectors used in this study. (E) Study design. Lhx2 was transduced on day 5. (F) Microscopic analysis of EGFP- and Lhx2-transduced cells. Original magnification: ×4. (G) Growth curves of hematopoietic cells from ESCs transduced with EGFP or Lhx2. (H) Annexin-V staining. EGFP⁺ cells were shown. (I) FACS analysis of KSL cells derived from RENKA ESCs. The relative frequencies (%) are shown in the corners. (J) The RT-PCR analysis Lhx2, Gata-2, c-Myc, and c-Kit.