Patent ID: 8465975

Claim:
A method of generating a high-purity population of late stage motor neuron progenitor cells, wherein the population has a purity of greater than about 65% late stage motor neuron progenitor cells, comprising: (a) neuralizing a culture of pluripotent stem cells by culturing pluripotent stem cells in a growth media that contains beta fibroblast growth factor (bFGF) and that lacks bone morphogenic protein (BMP), and that is supplemented with one or more of albumin, a fatty acid, a thyroid hormone, a vitamin, a trace mineral, insulin and transferrin; (b) ventralizing the neutralized cell population of step (a) comprising culturing the cell population under non-adherent conditions in a motor neuron media supplemented with retinoic acid and beta fibroblast growth factor (bFGF) for at least about five days, (c) incubating the ventralized cell population of step (b) comprising culturing the cell population in growth media with bFGF without retinoic acid to promote formation of neurospheres, (d) selecting the neurospheres; (e) expanding neurospheres on an adherent substrate to form a layer of cells comprising a population of cells comprising greater than about 65% late stage motor neuron progenitor cells, wherein said late stage motor neuron cells express markers of the motor neuron HB9, Ach, Isl1, Lhx3, and Lim1, but lack a functional calcium channel.