Longaker is the deputy director of Stanford's Institute for Stem Cell Biology and Regenerative Medicine and director of children's surgical research at Lucile Packard Children's Hospital. Wu is an assistant professor of cardiology and of radiology, and a member of Stanford's Cardiovascular Institute. A third author, Mark Kay, MD, PhD, is the Dennis Farrey Family Professor in Pediatrics and professor of genetics.
The finding brings together disparate areas of Stanford research. Kay's laboratory invented the minicircles several years ago in a quest to develop suitable gene therapy techniques. At the same time, Longaker was discovering the unusual prevalence and developmental flexibility of stem cells from human fat. Meanwhile, Wu was searching for ways to create patient-specific cell lines to study some of the common, yet devastating, heart problems he was seeing in the clinic.
"About three years ago Mark gave a talk and I asked him if we could use minicircles for cardiac gene therapy," said Wu. "And then it clicked for me, that we should also be able to use them for non-viral reprogramming of adult cells."
The minicircle reprogramming vector works so well because it is made of only the four genes needed to reprogram the cells (plus a gene for a green fluorescent protein to track minicircle-containing cells). Unlike the larger, more commonly used DNA circles called plasmids, the minicircles contain no bacterial DNA, meaning that the cells containing the minicircles are less likely than plasmids to be perceived as foreign by the body. The expression of minicircle genes is also more robust, and the smaller size of the minicircles allows them to enter the cells more easily than the larger plasmids. Finally, because they don't replicate they are naturally lost as the cells divide, rather than hanging around to potentially muck up any subsequent
|Contact: Krista Conger|
Stanford University Medical Center