A research breakthrough by scientists at the blood cancer charity Anthony Nolan could lead to better outcomes for patients having stem cell transplants using umbilical cord blood.

The team has found a simple way of activating the natural killer cells in cord blood units to potentially double the effects of the stem cells in the units.

This could reduce the risk of complications following a transplant and allow hospitals to save money by using just one cord blood unit, rather than two.

The researchers, led by Dr Aurore Saudemont at the Anthony Nolan Research Institute, also believe that their findings could lead to more patients being offered cord blood transplants and that this could improve long-term patient outcomes.

Dr Saudemont said: "We hope that in the short term we can improve the results for patients and make better use of the cord blood units that we have banked.

"The technique we have discovered is so simple that it could be used in hospitals that offer transplants all over the world. As a result, it could benefit a lot of stem cell transplant patients internationally."

The researchers have discovered that if they add a protein called IL-15 to the natural killer cells in a cord blood unit, these make the stem cells more effective, optimising the effect of the graft.

This technique is the subject of a research paper published in the scientific journal PLOS ONE.

The main issues faced by cord blood transplant patients are the delayed stem cell engraftment, potentially the long time for their immune systems to regenerate after the procedure and the high risk of infection.

The new method of preparing stem cells for transplant could increase their speed of engraftment and therefore the speed with which patients' immune systems regenerate, meaning they recover quicker and are less likely to develop dangerous infections.

As it would lead to better stem cell function, it would also reduce the risk of the transplant failing altogether by increasing the chance of stem cell engraftment.

And there could be more wide-ranging benefits, according to Dr Saudemont.

She said: "Currently just a quarter of the cord blood units collected following a birth can be banked for transplants as most do not contain enough stem cells.

"But, our research suggests that if the stem cells that are present can be made more effective, then cord blood units with fewer stem cells could also become suitable for transplants.

As a result, this would make the cord blood collection process more efficient and mean that more cord blood units were available for patients in need of stem cell transplants.

Better results from cord transplants could also lead to transplant doctors being more likely to use cord, instead of transplants using stem cells taken from poorly matched adult donors, when no well matched adult donor can be found.

This could benefit patients as those who receive a transplant using cells that are not very closely matched are at greater risk of post-transplant complications.

Dr Saudemont and her team are currently planning a clinical trial of the new technique and hope that it could soon be benefiting patients.

Anthony Nolan and Professor Bernat Soria at the Andalusian Centre for Molecular Biology and Regenerative Medicine (CABIMER) in Seville, Spain, have a joint patent covering the use of cord blood natural killer cells activated using this new method.