Cell being drawn off a small cluster under a microscope

Few areas of medical research are exciting as much interest as the potential offered by stem cell research and regenerative medicine.

Every day sees scientists making breakthroughs in a range of health conditions, each one driven by the prospect of using the human body to trigger defences. One of the most exciting recent developments has seen University of Cambridge researchers in the UK discover the strongest evidence to date that human pluripotent stem cells — cells that can give rise to all tissues of the body — will develop normally once transplanted into an embryo. Human pluripotent stem cells for use in regenerative medicine or biomedical research come from two sources: embryonic stem cells, derived from fertilised egg cells discarded from IVF procedures; and induced pluripotent stem cells, where skin cells are ‘reset’ to their original, pluripotent form.

They are seen as having promising therapeutic uses in regenerative medicine to treat conditions that affect various organs and tissues, particularly those that have poor regenerative capacity, such as the heart, brain and pancreas. However, some scientists have been concerned that the cells may not incorporate properly into the body, resulting in tumours. The latest study suggests that this will not be the case and that stem cells, when transplanted appropriately, are likely to be safe for use in regenerative medicine. They have now published a paper on the subject and Professor Roger Pedersen from the Anne McLaren Laboratory for Regenerative Medicine at the University of Cambridge, commenting on co-author Victoria Mascetti’s findings, said: “Our study provides strong evidence to suggest that human stem cells will develop in a normal — and importantly, safe — way. This could be the news that the field of regenerative medicine has been waiting for.”

Previous research has not succeeded in getting human pluripotent stem cells to incorporate into embryos. However, in research funded by the British Heart Foundation, Victoria Mascetti and Professor Pedersen showed that it is possible to successfully transplant human pluripotent stem cells into the mouse embryo and that they then develop and grow normally. Professor Pederson said: “Stem cells hold great promise for treating serious conditions such as heart disease and Parkinson’s disease, but until now there has been a big question mark over how safe and effective they will be.” Ms Mascetti’s research showed that when transplanted at the correct stage, the stem cells went on to grow and proliferate normally, to integrate into the embryo and to distribute themselves correctly across relevant tissues.

She said: “Our finding that human stem cells integrate and develop normally in the mouse embryo will allow us to study aspects of human development during a window in time that would otherwise be inaccessible.” Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, which helped fund the study, said: “These results substantially strengthen the view that induced pluripotent stem cells from adult tissue are suitable for use in regenerative medicine — for example in attempts to repair damaged heart muscle after a heart attack.”

“Our study provides strong evidence to suggest that human stem cells will develop in a normal – and importantly, safe – way. This could be the news that the field of regenerative medicine has been waiting for.”  Professor Roger Pedersen, Anne McLaren Laboratory for Regenerative Medicine at the University of Cambridge.