Transplanting stem cells from the nervous system of a fetus into people with progressive multiple sclerosis (MS) has reduced markers of the condition in an early-stage trial. Whether this also relieves symptoms or slows the condition’s progression is unclear.

MS is a neurodegenerative condition that can affect a person’s vision or limb movements. It occurs when the immune system mistakenly attacks part of the brain and spinal cord. Progressive MS is defined as the condition worsening over time, which affects about 10 per cent of people with MS and has few treatments to effectively control its symptoms.

Neural stem cells, which can give rise to any of the cells that comprise the nervous system, have shown promise in treating other neurodegenerative conditions, such as Parkinson’s disease.

To test the potential of stem cells in people with progressive MS, Martino Gianvito at Vita-Salute San Raffaele University in Milan, Italy, and his colleagues extracted neural stem cells from a 10 to 12-week-old fetus after it had been aborted voluntarily by its mother, who donated the fetus to scientific research.

The researchers injected four different doses of these cells into the spinal canal, which contains the spinal cord, of 12 people aged 18 to 55 with progressive MS.

The severity of the participants’ MS meant they were all bedridden before the experiment, says Gianvito.

The trial primarily looked at safety, with no serious, treatment-related adverse events reported over the two-year follow-up period.

Before their initial injection, the participants had a lumbar puncture to look for levels of neuroprotective molecules in their cerebrospinal fluid, as well as an MRI scan to determine their brain’s grey matter volume, which gradually reduces in people with progressive MS.

Three months after the injection, the participants had another lumbar puncture. Results suggest that all the participants had increased levels of anti-inflammatory and neuroprotective molecules in their cerebrospinal fluid.

Two years later, an MRI scan showed that those given the two highest doses had a lower rate of grey matter reduction compared with those given the two lower doses.

Whether these results will translate into reduced MS symptoms or condition progression over time is unclear. Tests showed that the participants’ motor speed didn’t improve in the two years after the injection, says Gianvito.

The participants were also still bedridden. However, their MS hadn’t worsened over the two years.

According to Gianvito, two years may not be long enough to gauge the treatment’s potential, with further research being required.

Journal reference: Nature, DOI: 10.1038/s41591-022-02097-3

News Source: Newscientist, 2354015-fetal-stem-cell-treatment-for-multiple-sclerosis-shows-promising-signs