Stem Cells Help Rats Recover Lower-Body Movement

The six were among 12 rats experiencing lower-body paralysis after
undergoing complete spinal transections. The six were assessed over seven
weeks and compared to a control group that had not received transplants.
Neuralstem published results of its spinal cord stem cell transplant in the
journal Cell, in a paper titled “Long-Distance Growth and Connectivity of
Neural Stem Cells After Severe Spinal Cord Injury: Cell-Intrinsic Mechanisms
Overcome Spinal Inhibition.”

According to the study, rats treated with NSI-566 showed significant
locomotor recovery, with most (57%) of the grafted cells turned into
neurons. Also significant, according to the company, was the number of axons
that emerged, extending over 17 spinal segments both above and below the
point of spinal cord lesion. The axons expressed synaptic proteins in the
host gray matter, suggesting they made synaptic contact with host spinal
neurons.

“The fact that these cells induce regeneration of axons and partial recovery
of motor function makes them relevant for testing for the treatment of human
spinal cord injury,” Karl Johe, Ph.D., Neuralstem’s chairman and CSO, said
in a statement.

According to the paper, retransecting the spinal cord immediately above the
graft abolished functional gain, a finding that Neuralstem said indicated
that the regeneration of host axons into the human stem cell graft was
responsible for the functional recovery.

Neuralstem has submitted an application to the FDA for a trial to treat
chronic spinal cord injury with NSI-566. The cells were used in a recently
completed Phase I clinical trial for amyotrophic lateral sclerosis (ALS or
Lou Gehrig’s disease).