Oligodendrocytes derived from human embryonic stem cells for remyelination and treatment of spinal cord injury

Patent Number: 7,285,415

The central nervous system is comprised of neurons and glia, with approximately ten times more glial cells than neurons. The function of glial cells is primarly to provide insulation(ie generation of myelin by oligodendrocytes), destroy pathogens/clear debris (microglia), provide structural support to neurons, as well as providing nutrients and growth factors.

Astrocytes are the most abundant type of glial and are involved in physically adjoining neurons to blood supply. Amongst numerous other functions, astrocytes actually regulate blood supply through production of vasodilators and vasoconstricting molecules. These cells actually signal to each other using calcium as well as a variety of other mediators.

Oligodendrocytes are a type of glial cell that coats axons in the central nervous system and produce myelin. Myelin acts as an insulator to ensure that inter-neural transmissions occur with efficiencies. In diseases such as multiple sclerosis, myelin is destroyed by the immune system, resulting in neural dysfunction.

The reason for this introduction is because the patent discussed covers methods of generating glial cells from embryonic stem cells. Specifically the inventors teach that culturing embryonic stem cells in the presence of a growth factor, a ligand for a thyroid hormone receptor, and a ligand for a retinoic acid receptor.

This patent is useful for the in vitro generation of cells suitable for transplantation to heal neural degeneration. Still there are two main problems: how would one implant such newly generated glia? and how would one overcome the issue of immune rejection since most embryonic stem cells are allogeneic to their potential recipients.

The second problem may be overcome by parthenogenesis-derived autologous cells, the first problem, we have no idea.

View this patent on the USPTO website.