The road from skin cell to stem cell mapped
A new study has mapped in detail the reprogramming of skin cells to stem cells. The results will hopefully lead to more efficient means of producing these cells, which the researchers hope to be able to use to treat diseases such as Parkinson's and MS in the future.
The discovery that specialised cells can be reprogrammed into immature cells, which in turn can be developed into all types of tissue in the body, was awarded the Nobel Prize in Physiology or Medicine. The method makes it possible to study cells that are normally inaccessible, such as brain cells in patients with Parkinson's disease. Rather than studying their brain cells, the researchers can use more easily accessible skin cells from the patients and then transform them into the nerve cells that they would like to study in the laboratory. But the methods for obtaining induced pluripotent stem cells, known as iPS-cells, have proved inefficient, and researchers have found it difficult to produce large amounts of cells.
In order to gain a better and more detailed understanding of the reprogramming process, an international research group - which included researchers from Karolinska Institutet - has mapped several steps in the transformation from skin cells, known as fibroblasts, to iPS cells. By measuring the expression of specific genes and the occurrence of certain receptors on the cell surface during the process, they have shown that the reprogramming into iPS that takes place in the laboratory goes via distinct sub-steps that are not present during normal cell development. According to Sten Linnarsson, researcher at the Department of Medical Biochemistry and Biophysics at Karolinska Institutet, the results are important for two reasons.
"Firstly, they offer deeper insight into the reprogramming process itself, which provides a deeper understanding of how cells can be transformed from one type to another. Secondly, they give us tools to develop reprogramming into a more efficient process", he says.
In the future, the researchers hope to be able to use iPS cells as a starting point to grow more cells that can be transplanted into the body and replace diseased cells in cases of diseases such as multiple sclerosis or Parkinson's.
The study was led by researchers at the University of Edinburgh and was conducted in collaboration with the German Research Center for Environmental Health. The research was primarily funded by the European Research Council starting grant and the Anne Rowling Regenerative Neurology Clinic.
High-resolution analysis with novel cell-surface markers identifies routes to iPS cells.
Nature 2013 Jul;499(7456):88-91