Spinal Cord Injury: Nerve Regeneration and Stem Cells
Inside the Fehlings' Laboratory for Neural Repair and Regeneration
SpU: What is your strategy to promote nerve regeneration?
Dr. Fehlings: Both the brain and the spinal cord lose the ability to regenerate after embryogenesis (early cell development). In the adult brain and spinal cord, inhibitory molecules are expressed that prevent cell regeneration. One of these inhibitory molecules is called Rho (Greek, rhō).
A few years ago, I led the world’s first clinical trial examining a recombinant protein Rho antagonist called Cethrin™ (BioAxone BioSciences, Inc., Cambridge, MA); a biologic drug administered to regenerate injured axons (nerve fibers) and reduce paralysis after spinal cord injury. This was hailed by Reader’s Digest as the breakthrough of the decade. While that was quite nice of the publisher to make such a statement, it was a little optimistic. Nonetheless, it was an important development.
Now we are moving Cethrin into a larger phase clinical trial (expected in 2015). This is quite exciting because the drug has the potential to induce plasticity or regeneration in the injured spinal cord.
SpU: How are stem cells utilized?
Dr. Fehlings: Our strategy involves the use of adult neural stem cells. We’ve chosen neural stem cells because they are the developmental building block of the brain and central nervous system, including the spinal cord.
We are examining strategies where we can take the patient’s own skin cells and transform the cells into what is called an induced pluripotent stem cell (a cell capable of becoming a different cell or tissue) through the introduction of transcription factors. Transcription factors are proteins that control genes. Next, the induced pluripotent stem cell—which is exactly matched to the donor and derived through a very accessible source (eg, skin, blood cells)—is transformed into any kind of stem cell. We are looking at doing this with neural stem cells.
SpU: Have you utilized stem cells clinically?
Dr. Fehlings: Earlier this year, I transplanted my first patient with adult neural stem cells. Now, these neural stem cells were not derived from the patient’s own skin. Rather, they were derived from a cell source from a tissue bank. The point is, my patient is starting to show some modest neurologic recovery, and it is very promising.
Dr. Fehlings serves as a member of BioAxone BioScience, Inc.’s Clinical Advisory Board.
To learn about Dr. Fehlings’ practice, click here.