<正>Objective To study the effect of Bmil gene overexpression on hematopoietic differentiation colony-forming assay of human embryonic stem cells.Methods Human embryonic stem cell H1 was co-cultured with mouse bone marrow mesenchymal stem cells OP9 to simulate hematopoietic differentiation in vitro.On the 8th day of co-culture,CD34+hematopoietic progenitor cells were selected