Dramatic growth of grafted stem cells in rat spinal cord, page 1

Dramatic growth of grafted stem cells in rat spinal cord

Building upon previous research, scientists at the University of California, San Diego School of Medicine and Veteran's Affairs San Diego Healthcare System report that neurons derived from human induced pluripotent stem cells (iPSC) and grafted into rats after a spinal cord injury produced cells with tens of thousands of axons extending virtually the entire length of the animals' central nervous system.

Writing in the August 7 early online edition of Neuron, lead scientist Paul Lu, PhD, of the UC San Diego Department of Neurosciences and colleagues said the human iPSC-derived axons extended through the white matter of the injury sites, frequently penetrating adjacent gray matter to form synapses with rat neurons. Similarly, rat motor axons pierced the human iPSC grafts to form their own synapses.

The iPSCs used were developed from a healthy 86-year-old human male.

"These findings indicate that intrinsic neuronal mechanisms readily overcome the barriers created by a spinal cord injury to extend many axons over very long distances, and that these capabilities persist even in neurons reprogrammed from very aged human cells," said senior author Mark Tuszynski, MD, PhD, professor of Neurosciences and director of the UC San Diego Center for Neural Repair.

For several years, Tuszynski and colleagues have been steadily chipping away at the notion that a spinal cord injury necessarily results in permanent dysfunction and paralysis. Earlier work has shown that grafted stem cells reprogrammed to become neurons can, in fact, form new, functional circuits across an injury site, with the treated animals experiencing some restored ability to move affected limbs. The new findings underscore the potential of iPSC-based therapy and suggest a host of new studies and questions to be asked, such as whether axons can be guided and how will they develop, function and mature over longer periods of time.

While neural stem cell therapies are already advancing to clinical trials, this research raises cautionary notes about moving to human therapy too quickly, said Tuszynski.

"The enormous outgrowth of axons to many regions of the spinal cord and even deeply into the brain raises questions of possible harmful side effects if axons are mistargeted. We also need to learn if the new connections formed by axons are stable over time, and if implanted human neural stem cells are maturing on a human time frame -- months to years -- or more rapidly. If maturity is reached on a human time frame, it could take months to years to observe functional benefits or problems in human clinical trials."

Between these studies: Gene inhibitor, salmon fibrin restore function lost in spinal cord injury in rodents, New clues to repairing an injured spinal cord, New device allows brain to bypass spinal cord, move paralyzed limbs & this current study, I am hoping that one day we will be able to help those who suffer with a spinal cord injury.

So far with this current study they haven't had any successful human trials but they are trying different types of stem cells. Who knows, maybe some of these researches from the different studies will get together to combine some of their techniques to see if they can work together to come up with a treatment/cure.