Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.
Better way to grow muscle. The specialized stem cells responsible for repairing muscle, the satellite cells, have always been difficult to grow in large quantities in the lab. They have a strong natural hankering to mature into muscle. Researchers have not been able to keep them in their stem cell state in the lab and that prevents creating enough of them for effective therapies for diseases like muscular dystrophy.
A team at the National Institute of Neuroscience in Kodaira, Japan, published what seems to be a simple solution to the problem. In a press release from the publisher of the Journal of Neuromuscular Diseases posted by Science Daily they reported that adding just one protein to satellite cells allowed them to grow indefinitely in the lab and expand to the point they could provide a meaningful transplant that resulted in muscle repair in mice.
“This research enables us to get one step closer to the optimal culture conditions for muscle stem cells,” said Shin’ichi Takeda from the institute.
The protein they used, leukemia inhibitory factor, and its downstream impacts on other genes is now the subject of their ongoing research.
Regenerating heart vessels. A CIRM funded team at Sanford Burnham Prebys Medical Discovery Institute (SBP) in San Diego and at Stanford University have shown that repressing a single gene can encourage the formation of new blood vessels in the heart. Creating those new conduits for oxygen after a heart attack could reduce damage to the heart muscle and prevent development of heart failure.
Building new blood vessels requires coordination of several growth factors and clinical trials evaluating individual factors have resulted in failure. The SBP team found that a single gene repressed all those needed factors and blocking it could let them do their job and create new blood vessels.
“We found that a protein called RBPJ serves as the master controller of genes that regulate blood vessel growth in the adult heart,” said senior author Mark Mercola, a professor at SBP and at Stanford, in an institute press release. “RBPJ acts as a brake on the formation of new blood vessels. Our findings suggest that drugs designed to block RBPJ may promote new blood supplies and improve heart attack outcomes.”
The authors also suggested that RBPJ itself might be beneficial in cancer if it can inhibit the new blood vessels tumors need to thrive.
Bionic patch as pacemaker. Chemists at Harvard have designed nanoscale electronic scaffolds that can be seeded with heart cells and are able to conduct current to detect irregular heart rhythms and potentially send out electrical signals to correct them.
“Rather than simply implanting an engineered patch built on a passive scaffold, our works suggests it will be possible to surgically implant an innervated patch that would now be able to monitor and subtly adjust its performance,” said Charles Lieber the senior author in a university press release posted by Phys.Org. The research was published in Nature Nanotechnology
With its electronics built into the patch that is integrated into the heart, Lieber suggested the bionic patch could detect heart rhythm problems sooner than traditional pace makers. Another use for the patch he suggested could be to screen potential drugs.
Alternate to Tommy John in pictures. Sports fans generally have a vague idea of what Tommy John surgery is. First performed on baseball pitcher Tommy John of the LA Dodgers in 1974, the surgery replaces a torn elbow tendon with one from another part of the body. A number of baseball players in the past couple years have made headlines because they sought out an alternative to this invasive procedure using stem cells.
The players sometimes improve, but with their high-priced team doctors also demanding extensive physical therapy and other interventions, we don’t really know how much of the improvement is due to the stem cells. I am not aware of controlled clinical trials looking at the alternative therapy.
But given how much it is in the news, I thought it would be good to share this excellent info-graphic from the LA Times explaining exactly what happens with the stem cell version of the Tommy John procedure. The Times posted the graphic yesterday, and then today, papers around the country ran stories that the most recent famous recipient of the cells, Los Angeles Angels lefthander Andrew Heaney, was going to have the old-fashioned surgery today because the stem cell treatment did not work in this case.
There may be some individuals, likely those with only partial tears who might benefit from this stem cell procedure that uses a type of stem cell that is not likely to replace tendons, but can release factors that summons the body’s natural healing apparatus to do a better job. But until more formal clinical trials are conducted, it will be hard for doctors to know who would and would not benefit.