Cytokines for expansion and cell culture of mouse hematopoietic stem cells to progenitor cells. Hematopoietic stem cells are self renewing pluripotent cells often characterized by the expression of CD34. Studies have shown that decreased expression of CD34 tends to correlate with the decreased self renewal properties and pluripotent potential. Culturing CD34+ cells in a cytokine mixture of SCF, FLT-3 Ligand, IL-6 and IL-3 for short time periods allows rapid expansion of immature and more mature hematopoietic progenitor cells in cord blood or bone marrow preparations. If the goal is to only expand the most immature progenitor and stem cells, it is recommended that a combination of TPO, SCF and FLT-3 Ligand are used (Catalog: PB-500-04). Either cytokine combination can also be supplemented with other cytokines to promote specific lineages.