A stroke therapy using stem cells extracted from patients’ bone marrow has shown promising results in the first trial of its kind in humans.
Five patients received the treatment in a pilot study conducted by doctors at Imperial College Healthcare NHS Trust and scientists at Imperial College London.
The therapy was found to be safe, and all the patients showed improvements in clinical measures of disability. It is the first UK human trial of a stem cell treatment for acute stroke to be published.
The therapy uses a type of cell called CD34+ cells, a set of stem cells in the bone marrow that give rise to blood cells and blood vessel lining cells. Previous research has shown that treatment using these cells can significantly improve recovery from stroke in animals. Rather than developing into brain cells themselves, the cells are thought to release chemicals that trigger the growth of new brain tissue and new blood vessels in the area damaged by stroke.
The patients were treated within seven days of a severe stroke, in contrast to several other stem cell trials, most of which have treated patients after six months or later. The Imperial researchers believe early treatment may improve the chances of a better recovery.
A bone marrow sample was taken from each patient. The CD34+ cells were isolated from the sample and then infused into an artery that supplies the brain. No previous trial has selectively used CD34+ cells, so early after the stroke, until now.
Although the trial was mainly designed to assess the safety and tolerability of the treatment, the patients all showed improvements in their condition in clinical tests over a six-month follow-up period.
Four out of five patients had the most severe type of stroke: only four per cent of people who experience this kind of stroke are expected to be alive and independent six months later. In the trial, all four of these patients were alive and three were independent after six months.
Dr Soma Banerjee, a lead author and Consultant in Stroke Medicine at Imperial College Healthcare NHS Trust, said: