Well, that paragraph certainly caught my eye this morning in the news, thanks to a friend for sending the link over.
My initial thoughts were two fold – I liked the idea that stem cell technology might possibly help people with MS since I have several friends who suffer from the debilitating condition, but it tempered by the phrase ‘resetting patients immune systems’. Regular readers of this blog will be familiar with the disastrous TGN 1412 trial at Northwick Park, which has been covered here previously see here and here. That study warned of the dangers of stimulating a normal immune system in homeostasis.
Let’s take a look at multiple sclerosis though. It’s an autoimmune disease where the fatty myelin
sheath, which wraps around nerve cells and speeds up their rate of
transmission, is attacked by the body’s own immune system.
Previous efforts with stem cells have tried to reverse that process with no success. The researchers decided that perhaps waiting until advanced disease when neuro-regeneration had set in was the problem. The next logical approach was to therefore look at early stage disease before the body is under attack.
21 people with early relapsing-remitting MS who had not responded to treatment with the standard drug, interferon
beta, after six months received an autologous stem cell transplant (aSCT). The patients had stem cells removed from their bone marrow, then receive chemotherapy to destroy all existing immune cells in the body, before
re-injecting the stem cells. The stem cells then developed into naïve immune
cells that do not see myelin as alien, and hence do not attack it.
years later, 17 of the patients had improved by at least one point on a
standard disability scale, while none of the patients had deteriorated. The study has just been published in The Lancet Neurology.
The authors concluded that:
“Non-myeloablative autologous haemopoietic stem cell transplantation in
patients with relapsing-remitting MS reverses neurological deficits,
but these results need to be confirmed in a randomised trial.”
I have to say that realising the patients received a stem cell transplant rather than some immune stimulant reassured me greatly. However, SCT is not a walk in the park – it is a known curative treatment for some forms of leukemia, but because it involves wiping out all the existing white blood cells, it weakens the patient and some die because they are unable to fight infection.
Interestingly, the patients received alemtuzumab as part of their SCT regimen, similarly to the Cambridge patients reported in the Guardian article highlighted below. Alemtuzumab is a monoclonal antibody approved for the treatment of leukemia, but it became a candidate for MS when it was realised that it dampens the immune system.
Larger scale trials are still needed to confirm the initial results, but so far it looks a promising approach for the treatment of early stage MS.
R BURT, Y LOH, B COHEN, D STEFOSKY, R BALABANOV, G KATSAMAKIS, Y OYAMA, E RUSSELL, J STERN, P MURARO (2009). Autologous non-myeloablative haemopoietic stem cell transplantation in relapsing-remitting multiple sclerosis: a phase I/II study The Lancet Neurology DOI: 10.1016/S1474-4422(09)70017-1