A new experiment is being hailed as the “best evidence yet” that stem cells could be used to repair heart damage (Reuters). The Guardian thinks it could lead to “off-the-shelf heart repair therapy for heart attack patients”. Previous attempts to inject heart muscle from stem cells into damaged hearts have ended with the introduced cells dying. So researchers developed a ‘cocktail’ to allow new cells to survive in rats. “We used to just squirt them (the cells) in a saline solution and say, ‘See you boys,’ and hope for the best. That was pretty dismal,” said Chuck Murry, study author and researcher at the University of Washington (Toronto Star).

Efforts to use stem cells in heart repair have also been hampered by problems with getting stem cells to turn into just heart muscle cells – previously only 1% of stems cells would turn into cardiac muscle. Using two proteins to encourage growth and then purifying the cells Murry’s team managed to convert 90% of stem cells into heart muscle cells. “Past attempts at treating infarcted hearts with stem cells have shown promise, but they have really been hampered by these challenges. This method we developed goes a long way towards solving both of those problems,” he said (press release).

The research appears in Nature Biotechnology (abstract). The company that sponsored the research has put out their own press release and The Street says their shares were up 8% in Monday morning trading.

Image: Heart muscle graft (bottom) in a rat heart damaged by a heart attack, with human-derived cells incorporated with scar tissue (middle) and regular heart muscle cells (top) / Michael Laflamme/University of Washington