Method for expansion of stem cells
A method of increasing the growth of stem cells by mixing the stem cells with a growth medium that has been conditioned by an incubation with placental tissue. The method increases the expansion of the stem cell population.
1. A method for the expansion or growth of stem cells without substantially inducing differentiation, the method comprising:
collecting cord blood from a human umbilical cord;
isolating CD34+ cells from the cord blood;
producing live placenta conditioned medium (LPCM) by incubating whole human placenta in a Dulbecco's modified Eagle medium (DMEM) in a sterile container, wherein the whole placenta is submerged;
isolating the LPCM; and
contacting at least one CD34+ cell with a supplemented DMEM comprising the LPCM and a cytokine cocktail comprising 20 ng/ml IL-3, 250 ng/ml IL-6, 10 ng/ml stem cell factor, 250 ng/ml thrombopoietin, and 100 ng/ml Flt-3L, wherein the concentration of the LPCM in the supplemented DMEM is 50%.
2. The method of claim 1 , wherein isolating CD34+ cells comprises a method selected from the group consisting of fluorescence activated cell sorting, magnet activated cell sorting, counterflow centrifugal elutriation, equilibrium density centrifugation, velocity sedimentation at unit gravity, and T lymphocyte depletion.
3. The method of claim 1 , wherein incubating whole human placenta in a DMEM comprises a period of at least 24 hours.
4. The method of claim 1 , further comprising decontaminating the isolated LPCM by a method selected from the group consisting of filtration, UV irradiation, X-ray sterilization, ozonation, and hyperthermia.
5. The method of claim 1 , wherein contacting at least one CD34+ cell with a supplemented DMEM comprises a period of at least 24 hours.
6. The method of claim 1 , wherein the supplemented DMEM comprises a growth factor selected from the group consisting of, IL-1, IL-7, G-CSF, GM-CSF, Epo, FGF-1, FGF-2, FGF-4, FGF-20, IGF, EGF, NGF, LIF, PDGF, bone morphogenic proteins (BMP), activin-A, VEGF, and forskolin.