A total of 15 patients with secondary MS and significant symptoms were recruited for the study, which is the first time the method has been tried on humans.
Animal tests showed that the method was safe and effective and the phase one clinical trial with humans was also a success.
None of the participants had deteriorated one year after the treatment and there were no severe side effects.
The procedure involves taking neural stem cells – a blank canvas that can turn into any tissue that is needed – from a donor and injecting them deep into the brain of MS patients.
The stem cells, which were cultured in a lab and originated from the brain of an aborted foetus, are injected into patients via a skull cannula.
All 15 patients received stem cells that were clones of one another and all came from one donor.
The cells were harvested, banked, frozen and grown in a lab, and one donor has provided stem cells for a similar project on ALS, or motor neurone disease, run by the same Cambridge team as the MS trial.
The MS and ALS trials were so successful that larger phase two trials are now being launched.
Around 40 people with fast-progressing ALS, which is a degenerative condition that progresses in a similar way to MS but is more aggressive, are expected to be enrolled before the end of the year.
Phase two clinical trial approved
The Telegraph also understands that a phase two clinical trial for MS has also been granted approval by AIFA, the Italian regulatory body.
Prof Stefano Pluchino, the study’s co-author and professor of regenerative neuroimmunology at the University of Cambridge, said that the stem cell therapy could in the future cure both ALS and MS.
More than two million people globally suffer from MS, with drugs available to reduce the severity of symptoms, but two-thirds progress to a debilitating secondary phase within 30 years.
The disease is the result of a malfunctioning immune system that causes white blood cells to attack tissues in the brain instead of invading pathogens.
Macrophages, for example, are large cells that engulf invading disease-causing entities but in MS patients a form of specialised macrophage called microglial cells attacks nerve cells, causing inflammation.
An insulating layer around some nerves, called a myelin sheath, is also damaged in MS patients and this interferes with signals being sent properly around the brain and the rest of the body.
The stem cell therapy is thought to work by resetting the immune system and recalibrating the white blood cells so they stop attacking the nerves.
‘An encouraging step’
“Our work has suggested that injected cells are able to survive and integrate in the brain, where some of them are able to differentiate into brain cells, while some remain as stem cells,” Prof Pluchino told the Telegraph.
“Injected cells combat the inflammation associated with chronic MS, both by killing inflammatory white blood cells, as well as by turning bad microglia and bad macrophages into good ones (e.g. those able to promote tissue healing and potentially also remyelination).”
It is hoped that future work may be able to repair and regrow damaged nerves, which could see MS patients actually heal and improve, but it remains debated whether this is possible.
The imminent phase two trials will shed more light on how the stem cells work to stabilise the deterioration of an MS patient’s nervous system and if recovery is plausible.
Prof Pluchino said: “We desperately need to develop new treatments for secondary progressive MS, and I am cautiously very excited about our findings, which are a step towards developing a cell therapy for treating MS.”
“The fact that our treatment was safe and that its effects lasted over the 12 months of the trial means that we can proceed to the next stage of clinical trials.”
Prof Angelo Vescovi, the project co-leader from the University of Milano-Bicocca, said: “It has taken nearly three decades to translate the discovery of brain stem cells into this experimental therapeutic treatment.
“This study will add to the increasing excitement in this field and pave the way to broader efficacy studies, soon to come.”
Caitlin Astbury, the research communications manager at the MS Society, says: “These results show that special stem cells injected into the brain were safe and well-tolerated by people with secondary progressive MS.
“This was a very small, early-stage study and we need further clinical trials to find out if this treatment has a beneficial effect on the condition. But this is an encouraging step towards a new way of treating some people with MS.”
The study is published in the journal Cell Stem Cell.