New stem cell method makes functioning liver cells
Oct 12, 2011
By Kate Kelland
LONDON (Reuters) - British scientists have developed a new stem cell technique for growing working liver cells which could eventually avoid the need for costly and risky liver transplants. A team of researchers led by the Sanger Institute and the University of Cambridge used cuttingedge methods to correct a genetic mutation in stem cells derived from a patient's skin biopsy, and then grew them into fresh liver cells.
By putting the new liver cells into mice, they showed they were fully functioning. "We have developed new systems to target genes and correct defects in patient cells," said Allan Bradley, director of the Sanger Institute. At a briefing about the work, Bradley said the technique the first success of its kind leaves behind no trace of the genetic manipulation, except for the gene correction. "These are early steps, but if this technology can be taken into treatment, it will offer great possible benefits for patients," he added.
Stem cells are the body's master cells, the source for all other cells. Scientists say they could transform medicine, providing treatments for blindness, spinal cord and other severe injuries, and new cells for damaged organs. Research is focused on two main forms embryonic stem cells, which are harvested from embryos, and reprogrammed cells, also known as induced pluripotent stem cells or iPS cells, which are reprogrammed from ordinary skin or blood cells.
When they were first discovered in 2006, iPS cells looked like a perfect solution to the ethical debate over the use of embryonic stem cells because they are made in a lab from ordinary skin or blood cells. Embryonic stem cells are usually harvested from leftover embryos at fertility clinics and their use is opposed by many religious groups.
But in recent years, concerns have been raised that iPS cells may not be as "clean" or as capable as embryonic cells. Last year, a group led by Robert Lanza, of the U.S. firm Advanced Cell Technology, compared batches of iPS cells with embryonic stem cells and noticed the iPS cells died more quickly and were much less able to grow and expand.
http://uk.reuters.com/article/2011/10/12/us-stemcells-liver-idUKTRE79B5GI20111012. Adaptado.
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