Stem cells are cells at the earliest stage in development that have the remarkable potential to specialise and become any tissue in the body. Embryonic stem cells can be isolated from unused embryos but are hard to obtain and there are numerous ethical concerns surrounding their use. An attractive alternative is offered by induced pluripotent stem (iPS) cells, as these are artificially generated by turning back the clock on older, already specialised cells taken from adult donors. Until now, scientists have struggled to find an appropriate type of cell in the blood that can be turned into a stem cell, and they often make iPS cells from skin or other tissues, which can require a surgical procedure such as a biopsy.
A team at the University of Cambridge grew cells from patients’ blood in the lab and isolated what are known as ‘late outgrowth endothelial progenitor cells’, which they then turned into iPS cells. These iPS cells can be turned into any other cell in the body, including blood vessel cells or heart cells, using different cocktails of chemicals.
Dr Amer Rana, who led the research, said: “We are excited to have developed a practical and efficient method to create stem cells from a cell type found in blood. Tissue biopsies are undesirable – particularly for children and the elderly – whereas taking blood samples is routine for all patients.
“Researchers can freeze and store the blood cells, and then turn them into iPS cells at a later stage, rather than having to transform them as soon as they are sourced, as is the case for other cell types used previously. This will have tremendous practical value – prolonging the ‘use-by date’ of patient samples.”
iPS cells are a useful tool to help researchers study disease, but the ultimate hope is that they could be used to grow tissues to repair the damage caused by conditions such as heart and circulatory diseases.
Shannon Amoils, Research Advisor at the British Heart Foundation, said: “iPS cells offer great potential – both for the study and potentially the future treatment of cardiovascular diseases. As iPS cells are made from the patient’s own tissue, they can be used to study diseases and hopefully one day to repair damaged tissue without being attacked by the body’s immune system.
“Being able to efficiently produce iPS cells using cells from a blood sample will make it easier for researchers to push this technology forward. But there are still many hurdles to overcome before this kind of technique could be used to treat patients.”
The study is published today in the journal ‘Stem Cell: Translational Medicine’ and was funded by the British Heart Foundation, theMedical Research Council and theWellcome Trust.
Image: White and red blood cells. Credit: Anne Weston, LRI, CRUK/Wellcome Images
Geti I et al. A practical and efficient cellular substrate for the generation of induced pluripotent stem cells from adults: blood-derived endothelial progenitor cells. Stem Cell: Translational Medicine 2012 [epub].