Washington:A promising discovery by MIT researchers has possibly shown the way to non invasive treatment of debilitating spinal cord injuries.

It hinges on certain stem cells within the spinal cord that might be persuaded to differentiate into more healing cells and fewer scarring cells following an injury.

Their results could spur creation of drugs is likely to restore mobility to 30,000 people worldwide afflicted every year with spinal cord injuries.

In a developing embryo, stem cells differentiate into all specialized tissues. But in adults, stem cells act as a repair system, replenishing specialized cells, but also maintaining the normal turnover of regenerative organs such as blood, skin or intestinal tissues.

Tiny numbers of stem cells in the adult spinal cord reproduce slowly or rarely, and fail to promote regeneration on their own. But recent experiments show that these same cells, grown in the lab and returned to the injury site, can restore some function in paralysed rodents and primates.

The researchers at MIT and Karolinska Institute (Sweden) found that neural stem cells in the adult spinal cord are limited to a layer of cube- or column-shaped, cilia-covered cells called ependymal cells.

These cells make up the thin membrane lining the inner-brain ventricles and the connecting central column of the spinal cord.

"We have been able to genetically mark this neural stem cell population and then follow their behaviour," said Konstantinos Meletis of Picower Institute for Learning and Memory, MIT and author of the report.

"We find that these cells proliferate upon spinal cord injury, migrate toward the injury site and differentiate over several months," he added.

The study uncovers the molecular mechanism underlying the tantalizing results of the rodent and primate and goes one step further: By identifying for the first time where this subpopulation of cells is found, they pave a path toward manipulating them with drugs to boost their inborn ability to repair damaged nerve cells.

"The ependymal cells' ability to turn into several different cell types upon injury makes them very interesting from an intervention aspect: Imagine if we could regulate the behaviour of this stem cell population to repair damaged nerve cells," Meletis said.

These findings have been published in July issue of the journal Public Library of Science - Biology. IANS