German researchers turn skin cells into stem cells

Jul 25, 2011, 10:31 GMT

Muenster/Hanover, Germany - German medical researchers have cured serious liver disease in mice using induced pluripotent stem (iPS) cells in an important first that shows promise for use in people with liver metabolism ailments.

The researchers from Muenster and Hanover took skin cells from the mice, returned them to an embryonic state and subsequently corrected a gene defect in the cells. The cells were then used to create healthy mice.

'For the first time, a living organism has been cured of an illness using iPS cells repaired using genetic methods,' researcher Tobias Cantz told the German Press Agency dpa.

Cantz's team from the Max Planck Institute for molecular biomedicine in Muenster and their colleagues at the Hanover-based Institute for Cell and Molecular Pathology published their results in the scientific magazine PLoS Biology.

They noted that research using iPS cells is broadly seen as ethically unproblematic, as embryos are not needed to provide a source for them.

'We have de-programmed the skin cells of mice with liver disease into iPS cells and subsequently corrected the gene defect that caused the liver disease,' Cantz said.

Using a method known as tetraploid embryo complementation, the researchers were able to produce healthy mice from the treated iPS cells.

'The animals are healthy, and their lifespan has not been shortened,' Cantz said. 'This demonstrates that IPS cells can be changed in such a way that the cause of genetically conditioned illnesses can be corrected, while the pluripotent characteristics are retained.'

Professor Hans Schoeler of the Max Planck Institute in Muenster emphasised the importance of the results: 'Current debate has been extremely critical of iPS cells, but our results show that liver metabolism diseases in mice can be treated with iPS cells.

'The cells are just as stable as embryonic stem cells and well suited to combined cell and genetic treatment,' Schoeler believes.

Cantz's researchers are currently working on culturing liver cells directly from the corrected iPS cells for later use in the body.

According to the Max Planck Institute, the long-term aim of the research is to take cells from patients, reverse them into iPS cells in the laboratory, correct them genetically and ultimately to induce them into the patient to effect a cure.

The cells acquired in this way would not suffer the kind of rejection from the body that usually causes problems with donated tissue.