Louis Carney III BME 281 October 8 th, 2013

 About 300,000 Americans a year suffer damage to peripheral and central nerves.  Nerves damaged in the PNS are sometimes able to regenerate on their own, however nerves in the CNS can not.  Years ago it was believed that depending on the severity of the injury to the nerves, there would be no hope in regenerating them.  Recently there has been a lot of funding into possible ways to regenerate these nerves.

 Stem cells have become one possible solution to nerve damage.  These cells are able to differentiate into myelinating cells and support the re-growth of nerve fiber.  Stem cells are believed to have the ability to generate almost any cells found within the brain and spinal cord including neurons and neural- support cells.  There are many different types of stem cells that are believed to have this capability.

 Shwann Cells -peripheral glial cells that form the myelin of the PNS  Embryonic Stem Cells- cells obtained from embryos  Bone Marrow Stromal Cells- multipotential stem cells that can be differentiated based on environmental conditions  Bone Marrow Mesenchymal Cells- cells that promote tissue repair

 Stem cells are cultivated and placed in culture dishes.  These cells will begin to multiply and spread across the surface of the culture dish.  After a few days the cells begin to overcrowd the dish and are transferred to new dishes.  This process, known as sub culturing, is done many times over a six month period of time.  Following sub culturing, what originally started as 30 cells may expand into millions of cells.  The cells are then frozen and stored for testing.  In theory, these cells may then be injected into patients with nerve damage and used to regenerate the nerve itself.

 Researchers at John Hopkins University tested the effectiveness of stem cells regenerating nerves in rats.  Stem cells that were previously cultivated were taken and injected into the fluid surrounding the spinal cord of paralyzed rats.  3 months after the procedure took place, almost all of the tested rats were regaining use in their hind limbs and were slowly beginning to walk again.  Scientists also discovered that the injected cells continued to travel throughout the spinal fluid and develop  It should be noted that this was a preliminary experiment and it is not known if these results would hold true in human testing.

 There are many ethical concerns involving stem cell use and cultivation.  It is estimated that once available to the general public, the cost for stem cell therapy could be between $200k-$400k.  The procedure is not guaranteed to work due to the complexity of the CNS.  It is believed that patients must be treated within two weeks of sustaining damage to the nerves in order for this to work.

 Hopefully with the use of stem cells, patients suffering from nerve damage and paralysis may one day regain some of the functions lost.  There has recently been a large amount of funding and research into stem cell use in order to try and help suffering patients.  Research into adult stem cells is becoming more common in the hopes to avoid ethical concerns involving embryonic stem cells.  Scientists hope that one day stem cells may be used to cure other medical conditions including Parkinson's disease.  It is not known whether or not this procedure for curing nerve damage will ever actually be implemented in humans.