British scientists make progress with altered stem cells

Oct 24, 2011, 12:22 GMT

London - British scientists have made progress in using stem cells for treating hereditary diseases in the future.

Researchers from the Wellcome Trust Sanger Institute in Hinxton used so-called induced pluripotent stem cells (iPS cells), taken from the skin cells of patients with a metabolism disorder.

They changed these cells into cells like those in the liver. The team led by Allan Bradley also changed the gene responsible for the disease using two previously discovered procedures, as they reported in the scientific journal Nature.

They introduced the human cells 'cured' in this way into mice with the metabolic disorder.

The hereditary metabolic disease concerned is called Alpha-1-antitrypsin Deficiency, which occurs as the result of the mutation of a single gene (monogenic disorder).

Both copies of the relevant genes in the patient need to be changed for the disease to show symptoms. According to the authors, the disease affects one in 2,000 people of northern European origin and can lead to cirrhosis of the liver, which in turn could necessitate a liver transplant.

Bradley and his team used a so-called 'jumping gene' (Transposon) for the gene manipulation, as well as zinc-finger nucleases.

Skin cells were taken from three patients with metabolic disease. Stem cells like these are seen as an ethically unproblematic alternative to embryonic stem cells, as they are not drawn from embryos. In the future they are set to be used in cell therapy for a variety of diseases.

As no tumour cells formed in the mice as a result of the intervention - by contrast with similar trials - the study authors believe the possibility exists of making progress using this method in treating monogenic diseases.

The human cells apparently integrated into the liver tissue of the mice, taking over their function there. However, the altered iPS cells received mutations in their genetic makeup, the significance of which required further research, Bradley and his colleagues wrote.