In both in vitro and mouse-tissue studies, the Weill Cornell group watched as the MASCs differentiated into the full range of cell types.
"We took them furthest when it came to endothelial cells," says Dr. Daylon James, a co-author and investigator in Dr. Rafii's laboratory. "In experiments in live mouse tissue, we were able to show that these MASC-derived endothelial cells did more than just form -- they also joined up with, and functioned alongside, other blood vessels."
MASCs also produced contractile "beating heart" cardiac cells, neurons, and muscle cells in the laboratory, the researchers add.
But challenges remain. "We still don't understand the exact biochemical and genetic 'switch' that tells the cells to become MASCs," Dr. Seandel says. "Discovering that switch will be crucial to our being able to create MASCs on a routine basis."
"The other hurdle is to repeat this success in human cells, by utilizing the same stem-cell markers, including GPR125 and also another specific marker, Plzf," states Dr. Pier Paolo Pandolfi, a collaborator in the study. Dr. Pandolfi is currently a professor at Harvard Medical School. Drs. Ilaria Falciatori, Sergey Shmelkov and Jiyeon Kim are other researchers in Dr. Rafii's lab, who are using GPR125 to isolate stem cells from other adult tissues with the potential of converting them into multi-potent stem cells with regenerative potential.
Still, the findings in Nature are extremely promising.
"For male patients, it could someday mean a readily available source of stem cells that gets around ethical issues linked to embryonic stem cells. It also avoids issues linked to tissue transplant rejection, since these 'autologous stem cells' are derived from the patient's own body," Dr. Rafii says. Given the pioneering surgical technology developed by the Department of Urology at Weill Cornell -- by Drs. Peter Schlegel, Marc Goldstein and
|Contact: Jonathan Weil|
New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College