The first human trial of a therapy for acute stroke that used patients’ own stem cells has shown very promising results recently. The findings have been published in the journal Stem Cells Translational Medicine.
The pilot study was conducted at Imperial College London and involved five patients. Following successful outcomes of the treatment in animal studies, the researchers used bone marrow stem cells, namely CD34+ cells that are precursors of blood cells and blood vessel lining cells. These cells are believed not to turn into brain cells directly, but rather stimulate the growth of new brain tissue and blood vessels in the areas injured by stroke.
For the treatment, the doctors collected bone marrow from each patient. Then they isolated CD34+ cells and transplanted them into a brain-supplying artery. The researchers treated the patients as early as possible to achieve the best results – each of the participants got stem cell injections within seven days of acute severe stroke. In contrast, in other stem cell trials, the patients were treated six months or later after the stroke. This was the first time ever CD34+ cells were used so early after the stroke.
The therapy proved safe, and all the patients demonstrated improvements in their condition. All the patients showed positive dynamics in their condition in clinical tests within six months after the stroke. Four out of five participants had the most severe stroke type. Only four per cent of people can survive and be independent six months later after the stroke of this kind. At the same time, all four trial participants with the stroke of this type were alive half a year later, and three were independent.
Partially due to early treatment, the researchers have seen very promising results. However, they caution that before starting larger trials, more studies are needed to figure out the best stem cell dose and timescale for treatment.