We're very excited about these stem cells. We're really on the cusp of making some big leaps forward.

Immediately after the injury, nerve cells inside die and others lose their ability to pass on signals.

The actual cells that we transplanted, the human cells, are the ones that are making myelin. We're extremely excited about these cells.

We show that these [stem] cells make connections with the nervous system of the mouse in a way that is appropriate and could mediate recovery. That's a big thing.

This work is a promising step, and supports the need to study multiple stem cell types for the possibility of treating human neurological injury and disease.

Mechanism is always important, because without understanding it, it's difficult to predict how animal data would translate to people.