Human embryonic stem cells （hESCs） have been successfully differentiated into hematopoietic progenitor cells with colony formation capacity and further into various kinds of blood cells including erythrocytes, megakaryocytes, neutrophils, nature killer cells and T lymphocytes . Nevertheless, the differentiation efficiency is extremely low. The differentiation usually involves complex steps such as embryonic body formation or co-culture with stromal cells, causing inconsistencies and difficulties in dissection of its molecular mechanisms [8,9]. Therefore, it is essential to establish a well-defined hematopoietic differentiation model that is independent of serum and stromal cells and much easier to manipulate genes for functional screening, thus the underlying molecular mechanism of hematopoietic differen- tiation of hESCs could be dissected more easily.
