During a session at the this week’s World Stem Cell Summit in San Diego, an international research team described an “astonishing” experiment in which a mouse model of multiple sclerosis was able to virtually totally recover and move normally after being transplanted with human neural precursor cells (hNPC). The scientists were able to show almost full recovery in the mice up to six months later.
The investigators, led by Jeanne Loring, Ph.D., from the Scripps Research Institute, included scientists from the University of California, Irvine and a group from Australia.
“Our goal was to demonstrate cell therapy for MS,” Dr. Loring told the audience.
According to Ronald Coleman, a graduate student working with Dr. Loring and who is at UC-Irvine, the team used mice infected with a neurotropic JHM variant of mouse hepatitis virus (JHMV) as a model for MS. They injected hNPCs derived from human pluripotent stem cells (hPSC) into the mice to explore treatment options for the disease.
The results were indeed astonishing, said Dr. Loring. Non-control mice were able to move about in a manner that can be described as consistent and long lasting. T-cell proliferation was reduced and T regulatory cell induction took place. The spinal cords of the mice not only did not undergo further demyelination but actually exhibited remyelination. The control mice dragged their legs around when they tried to move.
“The only problem was that the hNPCs themselves are not directly responsible for the cure. They are not even there when the mice start walking,” explained Dr. Loring. “Those cells are rejected after seven days and we start to see a therapeutic response in three weeks.”
Both Dr. Loring and Coleman believe that the hNPCs are secreting proteins, like cytokines, that do the actual repair work in the CNS of the mice.
“We identified a set of candidate proteins secreted by hNPCs and not by undifferentiated pluripotent stem cells,” continued Dr. Loring, who said the team plans to continue building on this initial research.