Having grown up in an era where to find your way around you had to use paper maps, a compass and a knowledge of the stars (OK, I’m not actually that old!) I’m forever grateful to whoever invented the GPS. It’s a lifesaver, and I daresay has also saved more than a few marriages!

Having a way to guide people where they need to be is amazing. Now researchers at Sanford Burnham Prebys Medical Discovery Institute have come up with a similar tool for stem cells. It’s a drug that can help guide stem cells to go where they need to go, to repair damaged tissue and improve the healing process.

In a news release Evan Snyder, MD, PhD, the senior author of the study, explained in wonderfully simply terms what they have done:

“The ability to instruct a stem cell where to go in the body or to a particular region of a given organ is the Holy Grail for regenerative medicine. Now, for the first time ever, we can direct a stem cell to a desired location and focus its therapeutic impact.”

More than a decade ago Snyder and his team discovered that when our body suffers an injury the result is often inflammation and that this then sends out signals for stem cells to come and help repair the damage. This is fine when the problem is a cut or sprain, short term issues in need of a quick fix. But what happens if it’s something more complex, such as a heart attack or stroke where the need is more long term.

In the study, funded in part by CIRM, the team took a molecule, called CXCL12, known to help guide stem cells to damaged tissue, and used it to create a drug called SDV1a. Snyder says this new drug has several key properties.

“Since inflammation can be dangerous, we modified CXCL12 by stripping away the risky bit and maximizing the good bit. Now we have a drug that draws stem cells to a region of pathology, but without creating or worsening unwanted inflammation.”

To test the drug to see how well it worked the team implanted SDV1a and some human brain stem cells into mice with Sandhoff disease, a condition that progressively destroys cells in the brain and spinal cord. They were able to demonstrate that the drug helped the stem cells migrate to where they were needed and to help in repairing the damage. The treated mice had a longer lifespan and better motor function, as well as developing symptoms later than untreated mice.

The team is now testing this drug to see if it has any impact on ALS, also known as Lou Gehrig’s disease. And Snyder says there are other areas where it could prove effective.

“We are optimistic that this drug’s mechanism of action may potentially benefit a variety of neurodegenerative disorders, as well as non-neurological conditions such as heart disease, arthritis and even brain cancer. Interestingly, because CXCL12 and its receptor are implicated in the cytokine storm that characterizes severe COVID-19, some of our insights into how to selectively inhibit inflammation without suppressing other normal processes may be useful in that arena as well.”

CIRM’s President & CEO, Dr. Maria Millan, says this kind of work highlights the important role the stem cell agency plays, in providing long-term support for promising but early stage research.

“Thanks to decades of investment in stem cell science, we are making tremendous progress in our understanding of how these cells work and how they can be harnessed to help reverse injury or disease. Dr. Snyder’s group has identified a drug that could boost the ability of neural stem cells to home to sites of injury and initiate repair. This candidate could help speed the development of stem cell treatments for conditions such as spinal cord injury and Alzheimer’s disease.”

The discovery is published in the Proceedings of the National Academy of Sciences (PNAS)