A recent study has investigated the use of stem cells as a treatment of ischaemic stroke. Stem cells are an attractive therapy since they have the potential to develop into many different types of cells in the body.
In adults, one of the main sources of stem cells is the bone marrow, a tissue found in the hollow interior of bones. Stem cells found in the bone marrow are called mesenchymal stem / stromal cells (MSCs).
Scientists have recently demonstrated that injection of MSCs into the brains of mice can help improve functional outcome after transient ischaemia, which models a blockage or blood clot in the brain like a stroke. It appears that these MSCs modify the inflammatory response in the brain by changing the expression of certain genes, largely affecting the immune cells called microglia and macrophages. By promoting an anti-inflammatory and pro-survival response, the number of nerve cells dying as a result of ischaemia was greatly reduced, leading to a better outcome.
One of the major benefits of these cells over other currently used anti-inflammatory agents is that they exert most of their effects locally at the site of injury, potentially reducing side effects. However there are some disadvantages including the difficulty of delivering cells directly into the brain. Whilst this study is promising there is still much research that needs to be carried out before stem cells are used routinely in the clinic to treat stroke patients.