grey matter-white matter regeneration

Wise Young · 04-20-2002, 03:39 AM

The vast majority of people with spinal cord injury have intact gray matter below the injury site. They should benefit from regeneration of axons that have been interrupted. The reason why I believe that regeneration will have beneficial effects is because we do not need to regrow the entire spinal cord. The spinal cord is very plastic and has the capability of making do with very few axons. Most people do not have transected spinal cords and have some axons that remain. Therefore, the goal of regeneration is to provide sufficient additional axons to cross the injury site and grow up or down the spinal cord to restore function.

Neuronal replacement is beginning to look feasible. Five years ago, I was not sure that we had any way of doing so. However, much evidence now suggests that the brain and the spinal cord is capable of adding new neurons and that adults have stem cells that are constantly producing new cells. Of course, they do not seem to be doing it sufficiently or fast enough to restore function and therefore adding some stem cells or boosting their activity may be the way to do this. Proof is not yet at hand that this is possible but I think that stem cell research is worth investing in. At the present, it is not clear whether adult stem cells can do the task as well as embryonic stem cells.

We should not be discouraged if, for example, the Diacrin trial does not show positive results at the phase 1 level. It is entirely possible that stem cell therapies *alone* will not restore function. We are very likely to need regeneration alongside stem cells to do the job. Obviously, if one is lacking the targets to which regenerated axons can connect to, the first thing to do must be to put the targets in. One way to do so is to place stem cells that can produce those targets.

What I believe the human fetal transplant (Gainesville) and the Diacrin fetal stem cell transplant trials are showing us is that it is safe to transplant such cells into the spinal cord. The human fetal transplant trial suggests that a short period of immunosuppression may be sufficient to prevent rejection of heterografts (cells from another individual). Both trials suggest that these cells will not grow out of control.

Wise.

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Switch to Hybrid Mode Threaded Mode

04-20-2002, 03:39 AM	#11
Wise Young Administrator Join Date: Jul 2001 Location: New Brunswick, NJ, USA Posts: 37,975	The vast majority of people with spinal cord injury have intact gray matter below the injury site. They should benefit from regeneration of axons that have been interrupted. The reason why I believe that regeneration will have beneficial effects is because we do not need to regrow the entire spinal cord. The spinal cord is very plastic and has the capability of making do with very few axons. Most people do not have transected spinal cords and have some axons that remain. Therefore, the goal of regeneration is to provide sufficient additional axons to cross the injury site and grow up or down the spinal cord to restore function. Neuronal replacement is beginning to look feasible. Five years ago, I was not sure that we had any way of doing so. However, much evidence now suggests that the brain and the spinal cord is capable of adding new neurons and that adults have stem cells that are constantly producing new cells. Of course, they do not seem to be doing it sufficiently or fast enough to restore function and therefore adding some stem cells or boosting their activity may be the way to do this. Proof is not yet at hand that this is possible but I think that stem cell research is worth investing in. At the present, it is not clear whether adult stem cells can do the task as well as embryonic stem cells. We should not be discouraged if, for example, the Diacrin trial does not show positive results at the phase 1 level. It is entirely possible that stem cell therapies alone will not restore function. We are very likely to need regeneration alongside stem cells to do the job. Obviously, if one is lacking the targets to which regenerated axons can connect to, the first thing to do must be to put the targets in. One way to do so is to place stem cells that can produce those targets. What I believe the human fetal transplant (Gainesville) and the Diacrin fetal stem cell transplant trials are showing us is that it is safe to transplant such cells into the spinal cord. The human fetal transplant trial suggests that a short period of immunosuppression may be sufficient to prevent rejection of heterografts (cells from another individual). Both trials suggest that these cells will not grow out of control. Wise.