Johns Hopkins scientists have developed a simplified, cheaper, all-purpose method they say can be used by scientists around the globe to more safely turn blood cells into heart cells. The method is virus-free and produces heart cells that beat with nearly 100 percent efficiency, they claim.
“We took the recipe for this process from a complex minestrone to a simple miso soup,” says Elias Zambidis, M.D., Ph.D., assistant professor of oncology and pediatrics at the Johns Hopkins Institute for Cell Engineering and the Kimmel Cancer Center.
Zambidis says, “many scientists previously thought that a nonviral method of inducing blood cells to turn into highly functioning cardiac cells was not within reach, but “we’ve found a way to do it very efficiently and we want other scientists to test the method in their own labs.” However, he cautions that the cells are not yet ready for human testing.
To get stem cells taken from one source (such as blood) and develop them into a cell of another type (such as heart), scientists generally use viruses to deliver a package of genes into cells to, first, get them to turn into stem cells. However, viruses can mutate genes and initiate cancers in newly transformed cells. To insert the genes without using a virus, Zambidis’ team turned to plasmids, rings of DNA that replicate briefly inside cells and eventually degrade.
Adding to the complexity of coaxing stem cells into other cell types is the expensive and varied recipe of growth factors, nutrients and conditions that bathe stem cells during their transformation. The recipe of this “broth” differs from lab to lab and cell line to cell line.
Reporting in the April 8 issue of Public Library of Science ONE (PLoS ONE), Zambidis’ team described what he called a “painstaking, two-year process” to simplify the recipe and environmental conditions that house cells undergoing transformation into heart cells. They found that their recipe worked consistently for at least 11 different stem cell lines tested and worked equally well for the more controversial embryonic stem cells, as well as stem cell lines generated from adult blood stem cells, their main focus.