Sick Kids reports:
“This new technique is simple and reliable and allows us to isolate the best stem cells quickly,” says Dr. James Ellis, principal investigator of the study, SickKids Senior Scientist and Associate Professor of Molecular Genetics at the University of Toronto. “This has exciting implications for studying disease and for future cell therapies.”
The new stem cells are being used to form a study on Rett syndrome, a form of autism.
The recent discovery that human skin cells can be reprogrammed into becoming stem cells can take up to four weeks to grow. By using the Green Fluorescent Protein the cluster of cells are easy to find.
Not only does the green protein help scientists find the cells but when the samples are inserted at the same time with a drug-resistance gene only the strongest and best stem cells survive.
[quote”We designed the green gene to be off in skin cells, but to turn on when they are reprogrammed to become stem cells,” says Dr. Akitsu Hotta, lead author of the study and a post-doctoral Fellow from Japan (funded by SickKids Restracomp Award). “We can then pick the best stem cell colonies that glow green under the microscope and expand them to study human disease.”
Rett syndrone is caused by a mutation in the MECP2 gene and affects nerve cell maturation in the brain. The ailment only targets girls. Researchers are using nerve cells from the patient stem cells. The hope is that one day the research being done now will enable a drug to be made that can correct the defects.
“We noticed that tumours did not form if we transferred pure populations of mature cells into mice, but if green stem cells were also present, tumours were quickly established,” says Ellis, Co-Director of The Ontario Human iPS Cell Facility located at SickKids, where researchers have used this new technique to isolate iPS cells from 10 patients with diseases such as cystic fibrosis. “The green gene effectively signals the presence of tumour-forming stem cells, and these could be removed before transplantation is performed.”
Future use of the green gene will also come with the suicide gene enabling the strongest cells to survive.
The research was supported by Ontario Ministry of Research and Innovation, the Canadian Institutes of Health Research, the Stem Cell Network, SickKids Foundation and the International Rett Syndrome Foundation and SickKids Restracomp Award.